A Common Misunderstanding Of Special Relativity

[AnssiH]

Are there no professional physicists that moderate this area of the forum to respond to the false claim that it is impossible in theory to devise an experiment for humans to optically observe Lorentz contraction ?

 

If there were competent professionals moderating this area they would immediately tell you exactly what I was saying. Length contraction is a direct consequence of defining simultaneity in the particular convention called special relativity.

 

Your response is a perfect example of the basic problem I am complaining about in the previous post. You have to understand it is almost impossible to say what do they mean by what they are saying in most papers about relativity because of basic ambiguity of our language. In the paper you are referring to, they may even themselves be interpreting their result as an optical view of length contraction. Yet, in actual fact their interpreted result must be directly based on the convention of establishing simultaneity via isotropic C in their lab frame.

 

Don't get me wrong though, no one is claiming that relativistic definitions are the same as newtonian definitions. It would be pretty naive to interpret this thread as asserting so. Newtonian definitions are far less accurate than relativistic definitions, and relativistic definitions are assumed to be exactly valid in every junction of this thread (at least in mine and DD's posts, quite clearly). That is to say, length contraction is seen as a valid representation of reality; and as such it is something that must exist in any equally valid representation in some form or another. It may or may not be called length contraction however. The fact that a certain logic can be represented in multitude of ways is under the focus here; that is why it is called "a representation of" reality.

 

So, in that paper, do you think they are asserting that their lab frame is a preferred frame, i.e that things moving in their lab frame are actually length contracted?

 

Or don't you think they understand the principle of relativity, and so they also understand that things are length contracted in terms of how they must be represented in our inertial frame. But at the same time, our choice of representation doesn't actually cause any physical changes to them?

 

You have to understand the critical difference here; It is entirely possible that objects actually length contract in ontological sense; meaning there is a preferred frame in which things have their "maximum length". Whether or not that is true, is impossible to prove because little thought would reveal every frame would appear observationally identical anyway; at least as long as the symmetries apparent in Maxwell's Equations are valid. Note that Newtonian definitions would not yield those symmetries as valid!

 

The fact that Newtonian view and Maxwell's Equations did not match was exactly the "paradox" that allowed Hendrik Lorentz to derive Lorentz transformations, which was effectively the first representation of the very logic we now call special relativity (and it does represent its own version of length contraction of course). The only difference is, Lorentz' representation form did not imply the principle of relativity for the speed of light.

 

All that Einstein did at that point was he took Lorentz' result, and applied principle of relativity to C*, and worked out the math from there.

 

That history is why it is still called Lorentz Transformation, not Einstein Transformation.

 

And what Hermann Minkowski did from that point on is he proposed an ontological construct of space and time that would behave how Einstein's version behaved. That is why it's called Minkowski spacetime, not Einstein spacetime.

 

And somewhere along the way, everyone forgot that all this was just a representation form of a logic that was required to paint a self-consistent picture of Maxwell's Equations! Meaning, relativity is a valid transformation mechanism between different inertial frame representations of the same electromagnetic apparatus. Furthermore it is a representation in which the inertial frames can all be seen as equally valid, by our free choice of using that particular transformation. And in doing so, each frame must represent moving things as length contracted, in order to paint a coherent picture between different frames.

 

The basic argument I'm making is simple, you have to understand the difference between actual reality, and a valid representation of reality. If you confuse the two, you will erroneously think the validity of SR means rather many things that are actually just an arbitrary belief towards a preferred representation form of the formalism behind SR.

 

This really is a great topic, I hope there was more people thinking about these things because it does go a fair bit deeper than this...

 

-Anssi

 

* It occurred to me that this comment may not sink in to the reader if they are not aware of the fact that the principle of relativity to C can be applied to Lorentz result without changing any observational property. Lorentz' result was known to be observationally valid by that time, and anyone who understands his logic, and understands why simultaneity of separated events cannot be proven (see my previous post), also understands why relativistic C doesn't change the "truth" of the equations. Surely Einstein understood this fact just as well as anybody, and I believe that is exactly why he has commented that he was absolutely convinced he was "right" before any experimental results; meaning that in observational sense, he was just as "right" as any other representation of the same relationships could possibly be.

Edited January 26, 2014 by AnssiH

[Doctordick]

Are there no professional physicists that moderate this area of the forum to respond to the false claim that it is impossible in theory to devise an experiment for humans to optically observe Lorentz contraction ?

Just as an aside, I personally have an earned Ph.D. in theoretical physics awarded by Vanderbilt University in 1971.

see:

 

http://adsabs.harvard.edu/abs/1971PhDT........50S

 

It constituted a calculation desired by the Oak Ridge National Laboratory.

 

When I was a graduate student I discovered that physics is divided into two categories: experimental and theoretical. I went into theoretical because I wanted to understand physics and I thought that was what theoreticians were interested in. It turned out I was wrong. Experimentalists spend time doing experiments to see if the numbers the theoreticians gave them agreed with the experiments. Theoreticians spend their time doing calculations to see what numbers the theories predict.

 

Being totally disgusted with the professionals, I started a business rather than continue dealing with the "professionals".

 

The only physicist I ever spoke with who showed any interest whatsoever in the questions which interested me was Richard Feynman. He promised to get back to me but apparently died before he was able to do so.

 

And, no, I don't think there are any competent "professional" physicists reading this forum.

 

Have fun -- Dick

[Bombadil]

No, I am not saying "the math is wrong"; what I am saying is that when you simply convert the representation from frame #1 to frame #2 you have not finished the job! In order to get an accurate picture of what you will see when you look, you must further take into account the length of time the light takes to get to your eyes. What that means is that it looks like it came from where it was at an earlier time. How much earlier depends on how far away it was.

 

So are you saying that when we use the Lorentz contraction to convert from one frame to another and then take into consideration the time that it takes for the light to get to us that the effect that the Lorentz transformation has vanishes and the universe once again appears Newtonian in nature?

 

I am of course referring here to the Galilean transformations when I say Newtonian in nature.

 

If this is the case, is the Lorenz transformation just there to simplify parts of the math and is ultimately not needed? Also how do you account for ideas like what anssiH is referring to when he says,

 

Yeah, it's not something I could have figured out in a hurry, but here's someone else's attempt;

 

http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html

 

If he hasn't made mistakes, 1 g acceleration works out as 28 years to travel 2 000 000 light years (in earth frame), even if you decelerate back to earth's frame for half of the trip.

 

If both observers see the same thing, one on the ship and one on earth won't the observer on the ship conclude that he is traveling far faster then light? I have always been under the impression that the observer on earth would be able to watch the whole trip unfold over a period of around 2 000 000 years and if the ship then returned they could then watch this as well. Are you saying that this is not the case and that in fact the ship can arrive long before the observer on earth can even consider seeing him and then return to earth before a person on earth can ever see the ship returning?

 

What you are failing to take into account is the fact that the above measurement presumes the speed of light is the same in both directions. An observer moving with respect to you will say that the length of the rod is different from what you are presuming and the time between the positions of the holes when the laser went through was different than what you presumed. He would assert the speed of light as measured by your device was too small in one direction and too large in the other. In fact, those differences are exactly what is being represented in the equations at the top of this post.

 

Actually after coming up with this it took me a little while to figure out how light could travel in both directions with the same rotation speed of the device at all, after realizing that light must of course be able to travel back though the device in the opposite direction without changing anything my only conclusion is that even though they are connected by a rod it is only an assumption that the angle between the holes will not change. This is represented by the dependence on x in the transformation on the time axis and an assumption about when to call events simultaneous in the experiment. But I am wondering, are you saying that this is also just an illusion as well, and that when the time that it takes for light to travel is considered, then any time dilation will also vanish?

 

In essence, the moving observer will obtain exactly the same picture of the universe as the rest observer. They will each say that the others calculation is in error as it is foreshortened in comparison to theirs. But the reference length they are using is also foreshortened by the same factor thus their actual answers will be the same. Only their time measurements will actually be different. In order to understand that difference you would have to read my book.

 

But the length of the other observer is not the only factor. The rest observer will say that the moving observer is racing away from the star, meanwhile the moving observer will say that the rest observer is racing toward the star. Are you saying that this has no effect on the situation?

 

You left out the most important bit; by which mechanism do you expect them to be different? In terms of relativity, they are expected to be the same, apart from an aberration effect that has an expected magnitude, and is taken to be an optical illusion.

 

OK lets start with the Newtonian case first and suppose that the ship has a constant length. In this case the spacing between the photon detectors must be farther apart. Since the light entered the ship at two points a fixed distance apart and since the ship was moving away from the source it spent a longer amount of time in the ship and so had a longer time to spread out.

 

The correction in this case is simple just take into consideration the time that the light spent in the ship and add the distance traveled by the ship in this time to correct the equations so that both can come to the same distance to the star. At this point I think it is worth pointing out that if we used the reference frame of the moving observer then he would see the other ship as moving towards the star and so would conclude that the light is not going to spend as much time in his ship before hitting the photon detectors and so to make their results the same would conclude that he needs to subtract some number from the length of his ship to calculate the same distances.

 

Now lets suppose that, as you seem to be suggesting, the Lorentz contraction is just right that the ship at rest and the moving ship measure the same distance between their photon detectors (and from the perspective of the observer at rest I don't have a problem with this possibility from the point of view of the rest observer though it seems that it would have to be proven to be consistent mathematically) then both observers must measure the same distance between the photon detectors, and for the observer that sees the other moving away from the star there is no problem but suppose that we were trying to make sense of this from the moving observers point of view.

 

Then from the moving observers point of view he sees the other ship moving towards the star and by the same argument as before concludes that the light is spending less time in his ship and so by the same argument as before concludes that to make the distance calculations the same he must add to the length of the ship, but all that using the Lorentz transformation will do is amplify this effect and he will still conclude that the ship is shorter then needed and so the light still spent less time in the ship, since the ship is moving towards the star this just has the effect of making the photon detectors closer together.

 

What my point is, is that I really don't see the symmetry that you are trying to get at for the two observers. Rather I see a sort of antisymmetry where each one sees the opposite thing as the other, for instance I see no reason that both observers will see the others ship as shorter then theirs' but rather they will see the ship as shorter when it is heading towards them and longer when it is heading away from them.

 

When they are even they will of course see the other ship as the same length.

 

Effectively in your proposal you are assuming that you know the simultaneity of events (regarding how those wheels actually rotate in relation to each others), which is based on the critical error; an unprovable assumption that electromagnetic information is propagating at constant speed to all directions in your frame; the very property we were supposed to measure has already been assumed to be known at the initial setup.

 

That is, I have assumed that the rod defines a sense of simultaneity of events. I have measured the one way speed of light but only by wrongly assuming that light will only travel one way though the device for any given speed of rotation, that is if a laser is set up on the other end it will pass though just as easily in the other direction. I have defined simultaneity by the position of the wheel and assumed that this is valid.

 

ACtually what DD was saying was in complete accordance to the math of relativity. It was exactly the expectations in the case that relativity is valid.

 

See that's exactly where the problem is, the way that relativity is usually represented is to imply that things like length contractions are real observable things that we would simply see if we were moving at those speeds. And when someone points out otherwise, it is easily taken to be a contradiction of relativity, when it is not. The problem is, relativity is often represented vaguely, or plain misprepresented, even by "reliable sources". There are many ways to say these things, and if someone says "the spaceship is seen as length contracted", they could mean the spaceship is represented or plotted in a spacetime diagram as length contracted, or it is optically seen as length contracted, or both.

 

In actual fact, in terms of relativity, it is just the way things are plotted in spacetime diagrams, and that fact is usually lost in most representations of relativity, although it is blatantly obvious if you understand the fundamental underpinnings of relativity.

 

How is this shown to be true? First of all, after my analysis above I can't side with anyone that says length contraction will just make things look shorter, which was my first impression, but rather it seems that the observed length of the ship will depend on what direction the ship is going, towards or away from the observer. Which is not something that I have heard before but on closer inspection of the Lorentz transformation I can't just dismiss this as just totally impossible as there is a dependence on v and x where there seems to be some effect on the actual sign used.

 

I will agree with you at one point though, if two observers are standing in the middle of their ships moving past each other, when they are even with each other, they will agree on the length of their ships. But after this point they will each say the other ship is shorter while, before this point they will each say the others ship is longer.

[AnssiH]

So are you saying that when we use the Lorentz contraction to convert from one frame to another and then take into consideration the time that it takes for the light to get to us that the effect that the Lorentz transformation has vanishes and the universe once again appears Newtonian in nature?

 

I am of course referring here to the Galilean transformations when I say Newtonian in nature.

 

If this is the case, is the Lorenz transformation just there to simplify parts of the math and is ultimately not needed?

 

No that's not what he is saying. Galilean view and relativistic view are not equivalent; Lorentz transformation is very much a necessary component of the relativistic view.

 

What he was saying is that the effects of Lorentz transformation implied by the way things are PLOTTED in a spacetime graph, is not at all the same thing as what the observers actually see. We don't see the light in its travel, we only observe it when it actually "touches" us.

 

The spacetime diagram version of that circumstance is entirely dependent on what do you take the simultaneity of events to be in the frame you are representing. That is an open parameter, and not a measurable quantity at all.

 

Don't mistake any of the following as claiming that relativistic view is irrelevant. All I'm pointing out is a rather silly way that relativity is commonly viewed.

 

If both observers see the same thing, one on the ship and one on earth won't the observer on the ship conclude that he is traveling far faster then light?

 

That depends on what is meant by traveling faster than light. In the convention of relativity, no he is not said to be moving faster than C. Think about this;

The earth observer PLOTS the moving observer as time-dilated so much, that only 28 years are measured by its clocks, while 2 000 000 years are measured by the earth clocks.

 

I'm sure you find it easy to agree with the above since you've heard about time dilation. But now notice, the flip side of the same coin is the ship must think it made it across all that distance in just 28 years. So, how does that play out?

 

Well, the moving observer PLOTS the distance between Earth and Andromeda galaxy as length contracting so much that it only takes 28 years to make it across that distance, without anything moving faster than C in its frame; i.e. in the CONVENTION of special relativity, the distance traveled is taken to be less than 28 light years, because it is PLOTTED as contracted during the travel. If you shrink the distance you plot, you will be able to say the time derivative of the distance comes out as less than C.

 

But, at the same time, the moving observer will in fact pass all the milestones placed between Earth and Andromeda galaxy, so was he moving across 2 000 000 ly in just 28 years, or was the rest of the universe kind enough to shrink itself during the travel?

 

Because it is fundamentally impossible to measure one-way speed of light, we cannot say whose distance reference is correct. That is why it is self-consistent to say what relativity says. In a funny way, the very fact that we cannot possibly know what C is in any single direction, is the cornerstone upholding relativity. Compare this to the common misconception, that relativity is based on us having measured the speed of light in whichever way direction. That common view is almost entirely upside down from the knowable hard facts (Which Einstein understood perfectly well himself, mind you).

 

And here we get into the actual semantical stupidity of special relativity, when people take it to literally mean the same thing as ontological reality. Is it smart to think the universe shrinks itself for our convenience to make that trip? No of course not. Is it not little bit smarter to realize we are really only talking about epistemological correlation between our definition of distance, isotropic C, simultaneity, and time measurements.

 

None of this means newtonian view is more correct. It is far far less correct.

 

I have always been under the impression that the observer on earth would be able to watch the whole trip unfold over a period of around 2 000 000 years and if the ship then returned they could then watch this as well. Are you saying that this is not the case and that in fact the ship can arrive long before the observer on earth can even consider seeing him and then return to earth before a person on earth can ever see the ship returning?

 

No that's not what it means. If you think the above comments through you can probably figure out how it works without anything passing past C in any plot. If not, I can explain it with more detail.

 

This is represented by the dependence on x in the transformation on the time axis and an assumption about when to call events simultaneous in the experiment. But I am wondering, are you saying that this is also just an illusion as well, and that when the time that it takes for light to travel is considered, then any time dilation will also vanish?

 

No, I'm just saying that any possible setup proposing to measure the one way speed of light, must propose what is the simultaneity of events; typically it is just tacitly assumed (without the proposer even realizing he is making that assumption) to be the lab-frame reference, which is the same thing as assuming isotropic C. A very short circle of belief.

 

If you understand fully the mechanism with which that ship makes it over 2 000 000 ly in 28 years in its own time, you can understand how that same idea extends to infinity. The ship can keep accelerating without running into any universal speed barriers. At any point of the trip, we could start considering the inertial frame of the ship as being in rest, and repeat the same thought experiment to some place that is in 2 000 000 ly away in terms of that frame, rinse and repeat, ad infinitum.

 

The flip side of that fact is that the concept of a "center frame" is meaningless. That is exactly the same thing as saying you cannot establish the simultaneity of two separated events. And thats the same thing as saying you can't measure one-way speed of light. And it's the same thing as saying there's no preferred frame.

 

It always amazes me how many people can accept the assertion "there is no way to tell which observer is moving" together with the assertion "near the speed of light a spaceship would not be able to accelerate anymore" without getting massive cognitive dissonance.

 

To resolve that dissonance is to understand what relativity actually means.

 

But the length of the other observer is not the only factor. The rest observer will say that the moving observer is racing away from the star, meanwhile the moving observer will say that the rest observer is racing toward the star. Are you saying that this has no effect on the situation?

 

It does have an effect, it's called aberration of light. See my very first posts to this thread, they discuss exactly this effect.

 

Note that it's an effect that must be accounted for as an optical illusion, otherwise navigation is impossible. When it is accounted for, the distance measurements work exactly like the OP described. The reason I brought it up was precisely to point out how this issue must be handled to be consistent.

 

Note that the relativistic version of aberration is different from the newtonian version; this is in fact a result of the difference in the definitions of length/time measurement (which are the flip sides of the same coin). Relativistic version would see almost all of the light approaching from the direction of travel, which is roughly (but not entirely!) the same idea as in Newtonian view the spaceship traveling much faster than C; e.g. moving fast enough to make it across 2 000 000 ly in 28 years. In relativistic view, this is still considered less than C.

 

OK lets start with the Newtonian case first and suppose that the ship has a constant length. In this case the spacing between the photon detectors must be farther apart. Since the light entered the ship at two points a fixed distance apart and since the ship was moving away from the source it spent a longer amount of time in the ship and so had a longer time to spread out.

 

The correction in this case is simple just take into consideration the time that the light spent in the ship and add the distance traveled by the ship in this time to correct the equations so that both can come to the same distance to the star. At this point I think it is worth pointing out that if we used the reference frame of the moving observer then he would see the other ship as moving towards the star and so would conclude that the light is not going to spend as much time in his ship before hitting the photon detectors and so to make their results the same would conclude that he needs to subtract some number from the length of his ship to calculate the same distances.

 

Your analysis is mostly correct. The only thing is that aberration is kind of a third layer on this whole conundrum;

1. Q: What do things look like in a spacetime plot?

A: Length contracted

2. Q: What distances does a spaceship measure in its own frame via the mechanism described in the OP?

A: Exactly the same distances regardless of its speed vs the speed of the universe.

3. Q: What optical effect the so-called "aberration of light" adds to this soup

A: Exactly what relativistic aberration describes, which the ship must compensate for in its calculations, otherwise it will eventually think the universe is condensed into a point up ahead.

 

Now lets suppose that, as you seem to be suggesting, the Lorentz contraction is just right that the ship at rest and the moving ship measure the same distance between their photon detectors

 

No, that's not what I'm suggesting, and that's not how it works either. In terms of the spacetime diagram plotted by the rest observer, the length contraction of the moving ship is never of the same amount as the aberration effect. You can find rough approximated amounts of these effects from my earlier posts. These effects are not directly related.

 

That is, I have assumed that the rod defines a sense of simultaneity of events. I have measured the one way speed of light but only by wrongly assuming that light will only travel one way though the device for any given speed of rotation, that is if a laser is set up on the other end it will pass though just as easily in the other direction. I have defined simultaneity by the position of the wheel and assumed that this is valid.

 

Yeah exactly, which means the propagation speed of C has already been defined prior to measurement. All the possible measuring systems you could imagine are a function of the propagation speed of C, and the way you imagine they behave is a function of the propagation speed of C. You can't measure C without knowing how they behave, and you can't know how they behave without knowing C.

 

You probably realize by now that this is also just the flip side of the same old mantra; there's no way to define preferred frame, and there's no way to say who is moving and who is at rest.

 

How is this shown to be true? First of all, after my analysis above I can't side with anyone that says length contraction will just make things look shorter, which was my first impression, but rather it seems that the observed length of the ship will depend on what direction the ship is going, towards or away from the observer. Which is not something that I have heard before but on closer inspection of the Lorentz transformation I can't just dismiss this as just totally impossible as there is a dependence on v and x where there seems to be some effect on the actual sign used.

 

I will agree with you at one point though, if two observers are standing in the middle of their ships moving past each other, when they are even with each other, they will agree on the length of their ships. But after this point they will each say the other ship is shorter while, before this point they will each say the others ship is longer.

 

No that is wildly incorrect, you are just confusing aberration effect with length contraction; two quite different things.

 

Things are plotted in spacetime diagram as length contracted (shrunk) whether or not they exist in front or behind the direction of travel, because the notion of simultaneity is redefined in the transformation (think about this; to measure the length of a moving object, you must know where the front end and the back end of that object was at any given single moment. You can't know this, because you can't know the simultaneity of separated events. But also since you can't know this, you can just decide something as long as your transformation is consistent. Redefine the simultaneity, also means you redefine the length of the object! That is what length contraction is; ignorance regarding the speed of C).

 

Aberration effect appears to move everything forward, which is the same thing as saying that objects residing directly behind the ship, will appear to be closer when measured with the method described in the OP. You already described this mechanism yourself so I'm sure you can figure it out.

 

-Anssi

[Doctordick]

Anssi, I will need to read your post over very carefully to see if you are making any errors in your representation of my assertions. If you have made errors (and I suspect you have) they are relatively subtle. For that reason, I will answer Bombadil's post first as most of his mistakes are quite clear.

 

So are you saying that when we use the Lorentz contraction to convert from one frame to another and then take into consideration the time that it takes for the light to get to us that the effect that the Lorentz transformation has vanishes and the universe once again appears Newtonian in nature?

Yes, if what you mean by "appears" is what you see with your eyes (essentially making the emotional assumption that the speed of light is infinite: i.e., the object you see is exactly where you perceived it to be when the photon hitting your retina arrives. This is not what physicists mean when they say "appears"! What they mean is where they presume it is when they set its position in what they consider to be the "correct reference frame".

 

I am of course referring here to the Galilean transformations when I say Newtonian in nature.

When I project a movie on the screen in a movie theater, the length of time it takes the photons to reach the retina of your eye is so small as to be totally unnoticed. The speed of light is thus not an issue in ordinary perceptions of "what is going on". I am not sure, but I think Newton was the first person to actually measure the speed of light. Essentially he measured the length of time it took one of the moons of Jupiter to go from being close to the earth (on the near side of Jupiter) to the being far from the earth (on the far side of Jupiter). If the speed of light were infinite, those two times would be the same (the moon would reach the far point exactly half way through its orbit). It turns out that the observed receding path took slightly longer than the returning trip. He explained that by the fact that the light coming from the moon at the far point had to travel farther. The speed of light was finite and I think he actually made an estimate of what the speed of light was.

 

Of essence here was the fact that, in order to calculate the correct orbit from the observations, one had to first correct for the finite speed of light. I think Newton had to correct for the motion of the earth during the period of interest. I went into theoretical physics because I thought theoretical physicists thought about theories. In fact, in my life, the only professional physicist I ever talked to who had any concern about theoretical physics was Richard Feynman and he died shortly after I talked to him. In actual fact, experimentalists design experiments to test the numbers the theorists calculate and theorists try to calculate the numerical results implied by the theories. Those calculations most often require a substantial number of steps. If the theorist thought he knew how to calculate a specific step correctly he generally did so. If he didn't know how to do it correctly, he would invariably presume the error was negligible and truck on.

 

That is essentially what you do when you present your device for measuring the speed of light. You have two disks on the same shaft, each with a hole at a specified radius from the shaft where the hole in one disk is at a different angle from the hole in the other. You then want to find the rotation speed such that light traveling parallel to the shaft goes through both holes: i.e., the time it takes the light to travel between the two disks is exactly the same as the time it takes the disks to rotate through that angular difference.

 

First (as to how the set up looks to an observer looking through the holes towards the light when the experiment is performed) he will see the two holes as perfectly lined up: i.e., he sees the light going straight through the holes to his eye! If he is looking at the device from any direction and the light going through the holes lights up the edge of the holes, he will see that reflected light as two points circling around the shaft. If he is on the center line orthogonal to the shaft, he will see those two lights perfectly aligned with the shaft. If he is off center, he will see the closer point slightly ahead of the other point. The distortion is exactly what he would expect knowing that the light which was traveling the greater distance would take longer to reach his eye. In other words he would be moved to correct for the finite velocity of light.

 

This is an edit of the above paragraph! I just read it and realized I had made an error in my description. The correct description should be: "If he is on the center line orthogonal to the shaft, he will see those two lights perfectly displaced by the original angle designed in the device.

 

Such errors are easy to make and it takes a careful analysis to assure no such errors have been made. I apologize for the error and can only comment that I am not perfect and do on occasion make errors, some of which can be quite serious. That is one of the reasons I post on forums such as Hypography. I want people to point out when I have made an error. Of real significance here is the fact that eliminating all errors is not an easy task.

 

Thanks for reading this!

 

Now let us look at the design of your device as you set up the thought experiment. Note that you assumed it was a rigid device. That was an error. When the device is made to rotate, it is necessary to apply angular acceleration. Since you do not know how to calculate the consequence of that acceleration (that takes a correct application of a general relativistic transformation) you simply presume the error in the assumption it was rigid was negligible and went on! But think about what you were presuming. If that error is truly negligible, then you are presuming the accelerating forces on both discs are identical. The means the application of that force arrived simultaneously at both disks: i.e., the length of time required for the mechanical force to transfer to the disks was zero. You have assumed whatever mechanical process transferred that force, it propagated faster than the speed of light.

 

Well, just as an aside, that force is generally assumed to be propagated by means of the forces between the atoms of the device. Those forces are presumed to be a consequence of electromagnetic effects and are thus very much influenced by the finite speed of light.

 

If this is the case, is the Lorenz transformation just there to simplify parts of the math and is ultimately not needed?

What is and what is not needed is strongly dependent on what you are talking about. If you are talking about the image on the retina of your eye, the calculations are quite difficult because what you see depends upon how far those photons have gone: i.e., from that perspective the correct apparent dynamic orbit of the moon of Jupiter is not at all the simple orbital motion calculated via Newton's equations. Life is much simpler if you calculate in Newton's frame of reference and then simply correct what you see as depending on the finite speed of light. Physicists normally have little concern with what you see; their concern is how do you calculate the orbit: i.e., their results are analyzed in a specific frame of reference unassociated with what you see.

 

What you must comprehend is that exactly how things work out there is not a known fact. Everything the theorists calculate is essentially an approximation of one sort or another and they certainly presume all the currently accepted theories yield the correct answers: i.e., a careful analysis would take into account ALL the possible errors in their presumptions. Something no professional scientist has any desire to do.

 

Relativity is exactly what changes do you make in order to change from one frame of reference to another. Galilean relativity was long ago shown to be inconsistent with Maxwell's equations though it was entirely general: i.e., it did not depend on the dynamics of relevant mechanics. Special relativity (the case where there are no accelerations between those frames of reference) was quite quickly a solved problem and "general" relativity (which needs to include accelerations) has, in my humble opinion, never been correctly accomplished by the scientific community. I have a solution (it is in my book) but no professional has looked at it because I am held by the professionals to be a certified crackpot.

 

This is represented by the dependence on x in the transformation on the time axis and an assumption about when to call events simultaneous in the experiment. But I am wondering, are you saying that this is also just an illusion as well, and that when the time that it takes for light to travel is considered, then any time dilation will also vanish?

No, I am not! In my opinion, the confusion here arises because of the physicist's definition of time. The scientific community uses two contradictory definitions of time and insists on making every possible misdirection of attention needed to avoid recognition of that fact. The first definition of time (the definition used by society for centuries) is that two entities can dynamically interact if and only if they exist at the same time: i.e., if we can touch each other, we exist at the same time. The other definition of time is clocks measure time. The difference between those two definitions is that the first does not allow action at a distance. Physicists like "action at a distance" because it simplifies a lot of the calculations required by their theoretical explanations of the universe.

 

Are you saying that this is not the case and that in fact the ship can arrive long before the observer on earth can even consider seeing him and then return to earth before a person on earth can ever see the ship returning?

No, I have never said any such thing. The definition of time I use in my analysis is "if we can touch each other, we exist at the same time". You should be able to comprehend that, under my definition of time, time is certainly not something which can be measured by a clock or any phenomena defined by simple dynamics (your heart beat or how long it takes you to turn your head). That is where the idea of theories comes in.

 

The rest of your post is simply confused as you are presuming what the physicists tell you is what you will see. The truth is that exactly what you will see is something they are trying to understand. But they really don't want to think about what it is that they want to understand (except for Feynman, he seemed interested)! Newton is accepted as one of the geniuses behind classical mechanics. He apparently invented calculus and via that calculus came up with some very powerful mathematical solutions to some simple dynamic problems. Since Galileo showed that an object dropped the same distance in the same time whether it was traveling horizontal or not (Galilean relativity), it occurred to Newton that perhaps that would explain the orbit of the moon.

 

If you assume the moon is falling towards the earth and traveling sideways sufficiently fast as to remain at the same altitude (that is, the same distance above the curved surface of the earth) you can quite easily calculate the expected orbital time. I did it once and obtained an answer along the line of a few minutes. In order to get the correct answer, you have to reduce the gravitational force on the moon by a rather large factor. Newton set the acceleration of gravity to be proportional to the inverse square of the distance from the center of the earth. Now do you think he did this because he had measured the difference in the acceleration of gravity at the top of a mountain compared to the gravity on the surface of the earth? I think he did that because it gave him approximately the correct answer: i.e., it took care of the discrepancy. So he had an explanation.

 

So he then calculated the orbit of the earth around the sun. I did that, assuming the moon calculation was the correct answer. I obtained a year length of centuries! In order to get the correct answer, you have to multiply the acceleration of gravity by a rather large factor. That factor turns out to be very close to the mass of the sun divided by the mass of the earth if you assume the whole volume of the sun has approximately the density of water and the earth is roughly the mass of rock. So Newton set the acceleration of gravity proportional to the mass of the gravitating body and managed to get the right answer. In fact, he used idea to set both the mass of the earth and the mass of the sun thus defining G. He never actually measured either. Henceforth, Newton's gravitational force which yielded the correct orbital times was used to define the mass of the gravitating body. Success! He had explained the whole solar system!

 

What I am getting at is that the theoretical attack on explaining the universe is a "by guess" and "by golly" attack. They guess some explanation and are quite often held to be crackpots until: "by golly" it gives the correct answer. Classical mechanics isn't taught today as it was fifty years ago (when I was a student). They used to spend a lot of time with Newton's equations changing the definitions of the variables so as to approximate various complex problems. It was that work which, in the old days, led to subtle relationships regarding how solutions changed with the variable changes. It was out of those complex "propagation of solutions" that the theories of quantum mechanics began. Again the theories developed by a "by guess" and "by golly" attack. String theory is pretty well still in the "by guess" stage today.

 

The issue is, exactly what the correct calculations to be done (to determine what you will see) is actually still an open issue. They are still guessing right and left and few people (including the professionals) actually know how to make the calculations even if their guesses were right. I have been pushing for a little logical examination of the problem for over fifty years (long enough to convince the professional physicists I am a crackpot). I tried to publish my ideas in some physics journals back in '82 and was told what I was doing was philosophy and of no interest to physicists. The philosophers told me it was mathematics and of no interest to them. And finally the mathematicians dismiss it as physics and of no interest to them. So I am trying to leave what I have discovered to future generations; that is why I wrote that book.

 

Have fun -- Dick

Edited February 5, 2014 by Doctordick

[Bombadil]

After reading doctor dicks post I have to say that what the biggest problem has been is that I have been assuming that what relativity was introducing was the needed transformations to describe “how the universe looks if the speed of light is invariant under velocity transformations”. After reading doctor dicks post though, this is clearly not what he is saying, and not what the case is. After reading his post I decided to ask if we were to calculate what the universe looks like given a finite speed of light, in particular if a ship is traveling away from us at some speed v, how long will it need to be if it looks the same length as it was to start with.

 

I did this simply because I feel that if it can't or isn't done at least once mathematically then something is just a little bit lacking. In any case it took very little work to have what looks to me to be exactly the inverse of the Lorenz transformation fall out as the transformation to arrive at the length of the ship, I won't go into details unless someone wants to see it. In short what it tells me is that what you are saying is exactly the case when the aberration effects that AnssiH is talking about are taken into effect, then the Lorenz transformation vanishes and what is actually observed is as though the transformation is never used and the speed of light were in fact at least as far as length go's infinite, which is exactly what DD has been saying.

 

I won't say that I didn't make any assumptions in showing this but I will say that it is sufficient to satisfy me, if any one wants to see what I did I can post it, or for that matter I suspect that there are those on this forum that could do it just as easily as I did.

 

In any event at this point I started to wonder what would it look like if the ship was traveling away from us at lets say far faster then the speed of light. I didn't try describing it mathematically but after a little thought I have little doubt that it would look as though it where traveling away from us at some speed less then light, in fact as its speed approached infinity the speed that the ship appears to travel at will come closer and closer to that of light but will never reach the speed of light and of course it could never appear to pass the speed of light. Which is at least an interesting idea to me.

 

The case in which the ship is heading towards someone though, is giving me a somewhat more difficult image to make sense of. The only thing that I can think of is that a ship traveling at someone would look like if it could continue to accelerated past the speed light is, there would be no problem watching it as long as its speed was less then that of light, however it would vanish as soon as its speed reached that of light at which time it would appear suddenly at it's destination or where ever its speed was once again less then light. And then, its journey to that point from where its speed exceeded that of light could be seen in reverse of how it traveled the distance with the exception that it may now appear to travel at a speed greater then that of light.

 

While I think that both of these ideas are interesting I don't know if ether one has any relevance on the discussion at hand.

 

But this leads me to the question what will a ship look like (what will an observer actually see) as the ship approaches the speed of light in a relativistic reference frame. My guess right now is exactly like what I just described above.

 

Yes, if what you mean by "appears" is what you see with your eyes (essentially making the emotional assumption that the speed of light is infinite: i.e., the object you see is exactly where you perceived it to be when the photon hitting your retina arrives. This is not what physicists mean when they say "appears"! What they mean is where they presume it is when they set its position in what they consider to be the "correct reference frame".

 

This is just incredible to me, the idea that we would place an object in a coordinate system where we presume them to be makes sense to me from the prospective that where they are when an interaction takes place is an important thing and to not do this presumes the maximum speed of an interaction, however to then use the word “appears” to refer to where the object is and not what it looks like from some vantage point just seems a sure way to confuse people.

 

I would think that where something is should be independent of what reference frame we are in. However, on the other hand what something looks like should depend on where we are, of course when I say reference frame I am referring to it's relationship to some other object of interest.

 

Of course there are a few details of what I just said to fill in but in short if something happens in one reference frame then it better happen in every other reference frame, and if something is at one location then it should be there in every one but this won't necessarily say where it appears to be. Otherwise things like collisions and interactions just would not make any sense to me.

 

My point is that, and from what you are saying the physicists would try to disagree, that to describe something there should be one variable of evolution of the whole system and any clocks should be written as functions of that variable and all interactions should be written as a function of that variable, If for some reason we want to know what the universe looks like from a particular clock and location, then the time we read on that clock (and I use the word very loosely here) must be a function of some variable t just like all interactions, just like all interactions that happen must be a function of that variable, for instance what we see.

 

Just to be clear and I think I already know what you are going to answer, that variable t floating around all of the Newtonian equations isn't meant to be taken literately to be time as in what a clock measures, is it. I mean, its just a variable that describes how the system evolves right? From what you are saying I suspect that that variable is taken by physicists to be literally what a clock measures.

 

No, I am not! In my opinion, the confusion here arises because of the physicist's definition of time. The scientific community uses two contradictory definitions of time and insists on making every possible misdirection of attention needed to avoid recognition of that fact. The first definition of time (the definition used by society for centuries) is that two entities can dynamically interact if and only if they exist at the same time: i.e., if we can touch each other, we exist at the same time. The other definition of time is clocks measure time. The difference between those two definitions is that the first does not allow action at a distance. Physicists like "action at a distance" because it simplifies a lot of the calculations required by their theoretical explanations of the universe.

 

By action at a distance do you mean a force that has an infinite propagation speed? If so isn't the idea of using such a thing somewhat of a case of don't tell the left hand what the right hand is doing, in that at the same time they are saying that the speed of a particle can't exceed that of light and particles are the source of force.

 

I have to wonder if all of this is why every time a physicist mentions the idea of something traveling faster then light they say that it is going to have to travel back in time, when the idea that something traveling faster then light having to travel backwards in time has always seemed like a confusion of when something happed? That is they are interested in what the clocks say and not when things interacted?

 

No, I have never said any such thing. The definition of time I use in my analysis is "if we can touch each other, we exist at the same time". You should be able to comprehend that, under my definition of time, time is certainly not something which can be measured by a clock or any phenomena defined by simple dynamics (your heart beat or how long it takes you to turn your head). That is where the idea of theories comes in.

 

Exactly why a different definition of time then “if we can touch each other, we exist at the same time” would be used in the case of physics calculations is somewhat puzzling me. I have always thought of time in a physics equation as an evolution parameter, it is there to keep track of when an interaction takes place or how a system changes. You seem to be saying that this is not what theoretical physicists use time for which is a new idea to me, and one that I can only see as leading to unneeded transformations and a great deal of confusion when it comes to asking when an interaction takes place.

 

What I am getting at is that the theoretical attack on explaining the universe is a "by guess" and "by golly" attack. They guess some explanation and are quite often held to be crackpots until: "by golly" it gives the correct answer. Classical mechanics isn't taught today as it was fifty years ago (when I was a student). They used to spend a lot of time with Newton's equations changing the definitions of the variables so as to approximate various complex problems. It was that work which, in the old days, led to subtle relationships regarding how solutions changed with the variable changes. It was out of those complex "propagation of solutions" that the theories of quantum mechanics began. Again the theories developed by a "by guess" and "by golly" attack. String theory is pretty well still in the "by guess" stage today.

 

No wonder that I have more then once read something out of a physics book and then wondered where the rest of what I was reading was explained, as what I had just read seemed to imply that the answer was just guessed at until something worked. It probably was not that there is no good reasons for the guess, just that it was a guess in the end.

 

In fact at one time I was trying to read a book by Heaviside, finally I had to stop as it just seemed like just what you are talking about, a constant attempt to guess a set of equations that would fit the given information, many of which just didn't work.

 

 

If you understand fully the mechanism with which that ship makes it over 2 000 000 ly in 28 years in its own time, you can understand how that same idea extends to infinity. The ship can keep accelerating without running into any universal speed barriers. At any point of the trip, we could start considering the inertial frame of the ship as being in rest, and repeat the same thought experiment to some place that is in 2 000 000 ly away in terms of that frame, rinse and repeat, ad infinitum.

 

I'm responding to Anssih last as I just have a few comments to make as I would like to conform that how I understand it as stated above is in agreement with doctor dick and with AnssiH, while I am having a hard time making this agree with what AnssiH is saying it seems to agree very well with doctor dick.

 

How about this for a mechanism, the speed of the ship only needs to be less then the speed of light in a relativistic reference frame, however if the observer made the measurements from on board the ship and then used Newtonian mechanics he would in fact come to the conclusion that he was traveling far faster then light. However, if someone tried to see his ship approaching from his destination they would not be able to see his ship at all, meanwhile if someone measured his speed from any location that could see his ship they will always say that the ship is traveling at a speed that is less then the speed of light.

 

Meanwhile if the ships course is plotted in that relativistic reference frame they will say that the ship never exceeded the speed of light, rather it was a case of length contraction.

 

No, that's not what I'm suggesting, and that's not how it works either. In terms of the spacetime diagram plotted by the rest observer, the length contraction of the moving ship is never of the same amount as the aberration effect. You can find rough approximated amounts of these effects from my earlier posts. These effects are not directly related.

 

OK can you pleas clarify what you are saying as it seems to be in direct conflict with everything that I just posted and with the statement made by doctor dick here;

 

Yes, if what you mean by "appears" is what you see with your eyes (essentially making the emotional assumption that the speed of light is infinite: i.e., the object you see is exactly where you perceived it to be when the photon hitting your retina arrives. This is not what physicists mean when they say "appears"! What they mean is where they presume it is when they set its position in what they consider to be the "correct reference frame".

[AnssiH]

After reading doctor dicks post I have to say that what the biggest problem has been is that I have been assuming that what relativity was introducing was the needed transformations to describe “how the universe looks if the speed of light is invariant under velocity transformations”. After reading doctor dicks post though, this is clearly not what he is saying, and not what the case is. After reading his post I decided to ask if we were to calculate what the universe looks like given a finite speed of light, in particular if a ship is traveling away from us at some speed v, how long will it need to be if it looks the same length as it was to start with.

 

I did this simply because I feel that if it can't or isn't done at least once mathematically then something is just a little bit lacking. In any case it took very little work to have what looks to me to be exactly the inverse of the Lorenz transformation fall out as the transformation to arrive at the length of the ship, I won't go into details unless someone wants to see it. In short what it tells me is that what you are saying is exactly the case when the aberration effects that AnssiH is talking about are taken into effect, then the Lorenz transformation vanishes and what is actually observed is as though the transformation is never used and the speed of light were in fact at least as far as length go's infinite, which is exactly what DD has been saying.

That is quite incorrect... Without seeing your analysis, I suspect you got the result you got because you implicitly set out to figure out how long the ship would have to be to appear in original length after Lorentz transformation. The result of such analysis would obviously display an inversion of Lorentz transformation. But also it would not have anything to do with the original problem.

 

There's multiple independent steps here and you are little bit confusing them together.

 

First step is to figure out how distances are plotted in a spacetime diagram.

 

Second step is to figure out how distances appear to a natural observer when they are measured via the operation described in the OP.

 

At this point the result is already that the Length contraction that is visible in the spacetime diagram, is not visible to the natural observer.

 

Third step which is outside the relevant scope of the OP; what is the expected magnitude of aberration of light. That effect does distort the optical results of the previous step, but at the same time the natural observer must compensate this distortion out from his view, otherwise he is always navigating to wrong directions. Imagine a star straight above your head, and then imagine yourself accelerating sideways suddenly. This way, you will catch a ray of light that would have missed your otherwise, and you will catch that ray of light in such an angle (due to your current motion) that makes it appear the star is no longer directly above your head. The angle implies the star has shifted towards your direction of acceleration. You can't use that information as a basis of your measurement of distances in the universe; you can't say the star suddenly leaped forwards because you started to accelerate.

 

That effect obviously exist in newtonian definitions too, just the magnitude is different under relativistic definitions. If you want to take a closer look, Einsteins derivation for the expected magnitude under relatistic definitions can be found from the original paper for special relativity;

http://www.fourmilab.ch/etexts/einstein/specrel/specrel.pdf

Chapter 7 "Theory of Doppler's Principle and of Aberration"

See the equation for [math]cos\phi' and the reasoning leading to that expression.

 

The exact magnitude is not important though to convince yourself that aberration effect will not compensate for Lorentz contraction in any way. Let's think about this case from the OP, we are catching star light from a star directly behind the ship, through two holes at the back of the ship, hitting two spots at a wall in front of the ship.

 

We look at this in a frame that is at rest with the star.

 

We create two identical ships in some distance from the star; one at rest, and other one moving away from the star.

 

We superimpose a situation where the moving ship is just passing the ship at rest; in particular we start from a moment where the rear plates are just passing each other. This is our t0.

 

Lorentz length contraction is expressed by;

 

[math]L_{moving} = L_{rest}\sqrt{1-v^2/c^2}[/math]

 

For the sake of simplicity, we are interested of a situation where the speed of the moving ship is such, that it is plotted as length contracted to 50% of the length of rest ship.

 

[math]0.5 = \sqrt{1-v^2/c^2}[/math]

[math]v = \sqrt{(1-0.5^2)c^2 }[/math]

[math]v = 0.866c[/math]

 

I.e. the moving ship is plotted as length contracted exactly in half, and moving about 86,6% of the speed of the rays of light.

 

This gives us pretty good basis for plotting how things play out in terms of the star frame. Let's say the rest ship length is 1 light second, so it takes 1 second from t0 until the light hits the front wall (in terms of our chosen frame).

 

In order for the two ships to optically measure equal separation to the light beams, the moving ship front wall would have to co-incide with the front wall of the rest ship at the precise moment the light rays hit the front wall.

 

The front wall of the moving ship is precisely at the midway point of the rest ship at t0, and after 1 second it must have travelled a length equal to 86.6% of the full length of the ship, meaning .866 light seconds forwards. It is .366 light seconds too far already when the rest ship front wall catches the light. Whatever time the light beams would still take to catch the front end, they will also separate more all that time, making it appear the star is closer optically.

 

You should be able to see that in order for aberration effect to exactly invert length contraction here, the length multiplier of moving objects would have to be precisely 0.5 at 0.5c, and 0.75 at 0.25c, and 0.25 at 0.75c so on. I.e it would have to be linear, which it is not.

 

Plus, if we did the same analysis for a star in front of the ships, we would get an opposite result.

 

This whole result is all due to plain and simple aberration, as seen from the perspective of each individual hole.

 

-Anssi

Edited July 16, 2014 by AnssiH

[AnssiH]

What you must comprehend is that exactly how things work out there is not a known fact. Everything the theorists calculate is essentially an approximation of one sort or another and they certainly presume all the currently accepted theories yield the correct answers: i.e., a careful analysis would take into account ALL the possible errors in their presumptions. Something no professional scientist has any desire to do.

 

...

 

So he then calculated the orbit of the earth around the sun. I did that, assuming the moon calculation was the correct answer. I obtained a year length of centuries! In order to get the correct answer, you have to multiply the acceleration of gravity by a rather large factor. That factor turns out to be very close to the mass of the sun divided by the mass of the earth if you assume the whole volume of the sun has approximately the density of water and the earth is roughly the mass of rock. So Newton set the acceleration of gravity proportional to the mass of the gravitating body and managed to get the right answer. In fact, he used idea to set both the mass of the earth and the mass of the sun thus defining G. He never actually measured either. Henceforth, Newton's gravitational force which yielded the correct orbital times was used to define the mass of the gravitating body. Success! He had explained the whole solar system!

 

What I am getting at is that the theoretical attack on explaining the universe is a "by guess" and "by golly" attack. They guess some explanation and are quite often held to be crackpots until: "by golly" it gives the correct answer. Classical mechanics isn't taught today as it was fifty years ago (when I was a student). They used to spend a lot of time with Newton's equations changing the definitions of the variables so as to approximate various complex problems. It was that work which, in the old days, led to subtle relationships regarding how solutions changed with the variable changes. It was out of those complex "propagation of solutions" that the theories of quantum mechanics began. Again the theories developed by a "by guess" and "by golly" attack. String theory is pretty well still in the "by guess" stage today.

 

The issue is, exactly what the correct calculations to be done (to determine what you will see) is actually still an open issue. They are still guessing right and left and few people (including the professionals) actually know how to make the calculations even if their guesses were right.

 

Great post btw. I was supposed to respond earlier but I forgot. It's pretty good example of the circularity of definitions we are always operating with, and also how few people, even professionals, really understand how that circle operates without ever really touching ground on any sort of knowledge about reality.

 

Also Bombadil think about how strange it first sounded to you that, for instance, one-way speed of light simply cannot be measured. The way you felt it could "obviously" be measured, and the way you could not at all see all the assumptions you instantly made in your mind in order to describe such measurement... That is exactly analogous to the reactions in these forums towards many assertions that DD has made in his presentation.

 

There is always a collection of naive realistic assumptions about reality being such and such - things that cannot possible be known! And must in fact always be mental concepts in our representation of reality (such as simultaneity or dimensionality)... yet they are instantly used as the underlying basis for logical analysis, and some naive realistic complaints about his representation.

 

Think about, say, the fact that we cannot possibly know what is the dimensionality of reality. A lot of people would fight that point "just look and you know it is three dimensional". Yet at the same time they accept there are hosts of valid ways to describe reality with all kinds of dimensionality definitions (without actually understanding that issue mind you, they just accept because their accepted authorities say so).

 

And if they followed what DD was actually saying, they would see a mathematical proof that the exact kinematics we are representing in 3 dimensional form can be logically represented with any other kind of dimensionality just as validly, making it completely arbitrary accident that we just so happen to represent reality the way we do.

 

It's really is quite silly to read those complaints once one understands what he was actually saying...

 

-Anssi

[Doctordick]

Hi Bombadil,

I have been slow to answer you because I find it difficult to avoid being misunderstood. You should take a look at "The Foundations Of Physical Reality" on the "Physics and Math" forum.

http://scienceforums.com/topic/27583-the-foundations-of-physical-reality/

I thought that I had made things pretty clear there but apparently I haven't as there have been no responses whatsoever. As a consequence, I have no idea as to what people think I am saying.
 

My attack is to lay out a specific logical representation capable of representing absolutely any information to be communicated without making any constraints whatsoever on what it is that is being represented. In essence, I totally lay aside the problem to be solved and instead work only with an absolutely universal representation of all possible solutions.

Absolutely everyone seems to presume I am developing a theory of some sort. I am not. I am merely trying to avoid being stupid! Religionists believe the foundations of their beliefs are absolutely true and most of them will go to extreme lengths to fight anyone who refuses to accept the correctness of their conclusions. Scientists believe the foundations of their beliefs are absolutely true and, again, most of them will go to extreme lengths to fight anyone who refuses to accept the correctness of their conclusions.
 

As a conscious being I am involved in a story. The perceiving part of my mind tells me a story of a world around me. The story tells of familiar objects. It tells of colours, sounds, scents belonging to these objects; of boundless space in which they have their existence, and of an ever-rolling stream of time bringing change and incident. It tells of other life than mine busy about its own purposes. As a scientist I have become mistrustful of this story. Sir Arthur Eddington, 1934.

However, he offers no logical attack on the implied difficulty - the validity of that story!

Please note the signature I use on my posts, "Knowledge is Power -- The most popular abuse of that power is to use it to hide stupidity!" What one has to understand is just how difficult it is to avoid hiding your stupidity from yourself; certainly Eddington came up with no way to avoid it. The perceiving part of my mind tells me a story and believing that story may be totally stupid but survival itself demands possessing some rational prediction of expectations so I go with the flow wherever it leads me. Believing it is another issue entirely.

It is quite clear to me that you are attempting to interpret what I say in terms of that "story" you perceive to be reality. What I am presenting is a logical conclusion deduced from a universal representation "capable of representing absolutely any information to be communicated without making any constraints whatsoever on what it is that is being represented." What you clearly want to do is to put some constraints on what is represented. You want to "understand" it: i.e., you want to convert my conclusions into an explanation you can hold as believable.

I use a representation [math](x_1,x_2,\cdots,x_n)[/math] to represent any conceivable circumstance in terms of a finite set of concepts labeled by the set of numbers denoted as the unknowns "x". Thus any dialog can be represented by a collection of such circumstances. If [math]P(x_1,x_2,\cdots,x_n)[/math] is taken to represent the probability the represented circumstance is valid, "P" can represent any conceivable explanation of any collection of circumstances. This is no more than a representation. Either find a fault in the representation or accept it as what it is, a universal representation of any and all explanations of anything.

In my presentation on the Physics-Mathematics forum, I show that the expression

[math]\frac{d}{da}P(x_1,x_2,\cdots,x_n)\equiv 0. [/math]

is true by definition even if P is not a mathematical function and, if [math]P(x_1,x_2,\cdots,x_n)[/math] were a mathematical function,

[math] \sum_{i=1}^n \frac{\partial}{\partial x_i}P(x_1,x_2,\cdots,x_n)=0[/math]

would be an absolutely required constraint. Of course, [math]P(x_1,x_2,\cdots,x_n)[/math] as defined is not and can not possibly be a mathematical function.

If you don't find the above rather astounding, I don't think you are following the logic.

But that is only the beginning. In my book, I carefully make subtle adjustments to my definition of "x", one step at a time. These adjustments in definition are made in order to circumvent the subtle problems of viewing P as a mathematical function. With every change in definition, I am very careful to maintain the absolute universality of the representation. Essentially, these labels were eventually transformed into points in a Euclidean geometry and the concepts they represented became represented by specific patterns of points. I gave the name "objects" to those specific collections of points.

In the end, I discovered that

[math]
\left\{\sum_i \vec{\alpha}_i \cdot \vec{\nabla}+\sum_{i\neq j}\beta_{ij}\delta(\vec{x}_i -\vec{x}_j) \right\}\vec{\Psi}= K\frac{\partial}{\partial t}\vec{\Psi}=iKq\vec{\Psi}
[/math]

is an absolute constraint required by the definition of "an explanation" and nothing else.

I discovered this equation in 1970 but could not find a solution and thus found it to be rather a worthless result (it is fundamentally a many body problem and not directly solvable). In 1982 I realized that Schrodinger's equation was in fact an approximation of my equation and was quickly led to a substantial collection of approximations identical to relationships found in modern physics. In fact, the entire field of modern physics appears to be little more than approximate solutions to my equation including electro magnetic theory, nuclear interactions, unification of the four forces, and both special and general relativity.

The point of all of this is the fact that it says absolutely nothing about reality. Everything I present is no more than absolute constraints required by the definition of "an explanation" and nothing else. If your beliefs are internally consistent, the numerical representation of the required concepts will obey my equation.

In this thread, we have been talking about relativity and the common misinterpretations embedded in most representations.
 

After reading doctor dicks post I have to say that what the biggest problem has been is that I have been assuming that what relativity was introducing was the needed transformations to describe “how the universe looks if the speed of light is invariant under velocity transformations”. After reading doctor dicks post though, this is clearly not what he is saying, and not what the case is. After reading his post I decided to ask if we were to calculate what the universe looks like given a finite speed of light, in particular if a ship is traveling away from us at some speed v, how long will it need to be if it looks the same length as it was to start with.

When you bring up "how the universe looks ... ", your general picture (the story your mind spins for you) omits a great number of important issues. Scientists are very interested in coming up with approximate mathematical predictions of phenomena. These predictions are based upon their theories (those guesses as to what they think the rules of reality are) and they want their calculations to be as easy as possible (they want to be able to use the simplest calculations they can).

Take, for example, Newtons calculation of the orbit of the moon. First, it is an approximate calculation; he is not going to do it to the nearest inch. And second, the calculation would be very difficult if he used the center of his head as the origin of his coordinate system. The rough center of the earth is a much better choice though it certainly is not going to produce how things would actually look to him. You should comprehend at this point that scientists seldom even concern themselves with "how things actually look to them". Their interests are with regard to consequences to expect from experiments.

Anssi's concern with aberration effects center on the issue of how things look not on how to calculate the circumstance being examined. In fact, those aberration effects are calculated under the assumption light follows a straight line; i.e., when you go to consider aberration effects you are most definitely presuming you already know what is actually going on. When you go to consider phenomena involving light, your knowledge of what is actually going on must be very precise. An error of one millionth of a second is equivalent to an error of close to a thousand feet (light travels at about 186,000 miles per second).

So let us consider the problem of how a moving ship looks to us when it is traveling at a velocity close to the speed of light. As I said, you have to be very precise here. The first thing is to know exactly where each and every point defining that ship is. The length of the ship is clearly a function of the forces holding the thing together so we need to examine exactly how to calculate those forces in order to know the correct structure of the components making up that ship.

Now here is the first problem confronting us. In our frame of reference, the speed of the light on board the ship, going in the same direction as the ship, takes a long time to arrive at its destination. On the other hand, light going in the other direction is very quickly overcome by the arrival of its destination coming towards it. The problem we have is that according to modern physics, the electromagnetic forces holding atoms together are mediated by photon exchange. Just how can we be sure that moving does not yield changes in the shape and structure of the ship? In fact, as an aside,that is exactly what the Michelson-Morley experiments were all about! They were going to use the absence of change in structure to measure the speed at which the earth was moving. They got zero

Well, to make a long story short that problem was solved by presuming Galilean relativity was wrong! That is, you don't just add or subtract the associated velocities (as Galileo had guessed) but had to use the special relativistic coordinate changes. Those are the changes in coordinates we are talking about in this thread.

What I am trying to point out to you is the fact that the calculation of how that ship appears to the rest observer must include structure changes due to that inequity in photon exchange. The easiest way to include those structure changes is to make a special relativistic conversion to a frame of reference moving with the ship, presume all the physics is exactly the same as in our rest frame, guess that the ship will structurally identical to a its drawings when it was at rest and finally, construct the relevant image on your retina. That is not a simple procedure.

So just for the fun of it let us see how long that ship will appear to be (of course, assuming the above analysis is valid) if one photon is coming from the front of the ship and the other is coming from the rear. So let's look at one specific moment. I pick the exact moment the center of the ship passes a line through my eye perpendicular to its path. I picked that point for the simple reason that the result I expect will be that both photons will take exactly the same time to reach my eye. I will pick the time (in my frame) at which the front of the ship and the rear of the ship are exactly the same distance from specified point (it is after all, the position of the ship when I am making the measurement).

I will set the two coordinate systems such that their origins are on the intersection of that line through my eye and the path of the ship at the time the center of the ship crosses that line. Now, in the moving frame the front of the ship at t=0 will be at +x and the rear (at the same time) will be at -x (where x is half its length). The photons we are interested in are the ones which reach our eye at t'=dc where d is the distance between our eye and the path of the ship. What we have to do is back figure where these photons started as represented in the primed coordinate system (our rest frame). That is not a simple conversion of positions in the ships coordinate system.

I will presume the front photon came from +f on the line defining the path of the ship. The rear photon then came from -r. The distance traveled by the front photon was [math]\sqrt{d^2+f^2}[/math] and must have started [math]\frac{\sqrt{d^2+f^2}}{c}[/math] seconds before I saw it. Likewise, the rear photon traveled [math]\sqrt{d^2+r^2}[/math] and must have started [math]\frac{\sqrt{d^2+r^2}}{c}[/math] seconds before I saw it. In other words, I need to convert those two positions and times to the unprimed coordinate system in order to determine where they started in the ships coordinate system.

By definition, the center of the ship lies at t=t'=0. The front photon started at [math]t'=\frac{\sqrt{d^2+f^2}}{c}[/math]. Converting that time to the corresponding time in the moving frame, the front photon started at ...

How about someone out there calculate the supposedly correct answer. It would be fun to see what it would actually be.

I was just looking up the "latex" version of that time conversion needed here when I saw that Anssi had created an excellent reply to your post. This post of mine has already gotten so long as to be sort of "not worth reading". On the other hand, if you can follow the above, you should have a decent handle on what kind of calculations are necessary to get the supposedly correct answer. You have to convert the times above into the ships coordinate system and then figure out where the front and rear of the ship was at that time in the ships coordinate system. Then, having found that position, you must convert that position to the primed coordinates (where these points were when the photons started their trip). As I said, it is not a trivial problem and exactly what you should see is not near as simple a conversion as you see it to be. I think these are the aberration effects Anssi is talking about.

But getting back to what you will actually see, I again bring up that visual error of a millionth of a second mentioned earlier. It should be clear to you that your visual acuity is no where near the task if the speed of the ship is close to the speed of light. What you are going to see is a blur as it goes by and estimating its length will certainly be outside your visual abilities.

What I was trying to show is that the simple conversions you are thinking of are not up to the task. And, Anssi, regarding an earlier discussion we have had, if you want to know where you are going and when you will get there, your best bet is to simply work with a rest map of the universe and the time clock on your ship and just not worry about the fixed speed of light. I think I can pretty well show that, if interstellar travel is ever achieved, the ships will be accurately navigated by just such a procedure.

The central issue of the above argument has to do with my definition of time, that coordinate axis orthogonal to (x,y,z) and is what is measured on one's clock. The projection due to the quantization of mass (momentum in that direction) projects out differences and path lengths end up defining interactions.

Have fun you guys - I am tired of typing -- Dick

 

Edited May 19, 2014 by Doctordick

[Bombadil]

 

I've read the opening post several times and the only conclusion that I can come to is that you are trying to say that both a moving observer and a rest observer will measure the same distance to a star. Actually after quite a bit of thought on the matter and a reading about relativity this makes a little bit of sense that this is the case.

 

That is quite incorrect... Without seeing your analysis, I suspect you got the result you got because you implicitly set out to figure out how long the ship would have to be to appear in original length after Lorentz transformation. The result of such analysis would obviously display an inversion of Lorentz transformation. But also it would not have anything to do with the original problem.

 

 

While this is not what I did, after reading some on special relativity, something that I should have done some time ago and clearly need to read more on, something that I am doing. What I think that I did was inadvertently stumbled on the idea of Terrel rotation without realizing the implications, something that I had never come across until recently, and something that you should look into as it is an interesting consequence of the adoration of light that you mention.

 

In any case, the truth is, for the most part I have only ever thought of relativity as some sort of abstract set of transformations that are preformed on moving objects and never really took the time to understand it differently, now I am starting to see that this is perhaps the worst way and least interesting way of looking at it.

 

This is clearly something that I should have done quite some time ago.

 

 

The rest observer is using the manufacture's drawings for the length of the ship; not the apparent length he deduces from the relativistic transformations. In my example they are both using exactly the same length reference! If you are bothered by the fact that the rest observer cannot make his measurement at the same time as the moving observer because the ship is in the way, note that the only important issue is the position of the ship's detector at the moment the detector detected the photon on board the ship (that gives the moment at which the measurement was made from the moving ship's frame of reference). Since the ship is moving, that distance measure will change with time! The position of that detector at the moment the detection was made defines the specific moment of interest. The rest observer (at rest with respect to the distant object to which the measurement is being made) can delay his experiment to whatever time is convenient as he is not moving with respect to the distant object and he will obtain the same answer no matter when he goes to make the measurement!

 

 

After reading this several times one of my first thoughts that came to my mind is the words “So What?”, if both observers use the same length for the ship, and they make their measurements in the y,z directions of the ship moving in the x direction, then of course they will come to the same distance to the star. But this says nothing about how far that they will say that the star is in there reference frame.

 

However after some thought on the matter I have to come to the conclusion that if we disregarded the effect that the adoration of light has then of course both observers must say that the star is the same distance away as long as both do it in the same way. Otherwise we can distinguish the reference frames.

 

Now this at first seemed to me to be a rather fictitious situation as how can we just ignorer the adoration effects, however after reading about Terrel rotation I have come to the conclusion that this is the case, no matter how we preform the experiment both observers must say that the star is the same

distance away.

[AnssiH]

While this is not what I did, after reading some on special relativity, something that I should have done some time ago and clearly need to read more on, something that I am doing. What I think that I did was inadvertently stumbled on the idea of Terrel rotation without realizing the implications, something that I had never come across until recently, and something that you should look into as it is an interesting consequence of the adoration of light that you mention.

 

Well well, I had no idea someone had invented a name for that particular effect. Here's an interesting little detail from a web page I found by googling "Terrell Rotation";

 

"It was assumed for 50 years that the Lorentz contraction could be photographed; that objects would appear contracted in the direction of motion, and that that was the extent of the relativistic distortion. In 1959 James Terrell and Roger Penrose independently realized that this was not the case."[/size]

 

As you mention, this is a pretty straightforward consequence of aberration of light, and that is already clearly deduced in the original paper for SR. It shouldn't take 50 years to figure something like that out when me and you can figure it out with little bit of thinking.

 

I'm sure there were individuals over the years who figured it out without giving the effect any name, but the fact remains that most people just are not interested of thinking. They just accept what they hare from their chosen authority. So on the web pages I goggled they are saying many representations of relativity were incorrect up until 1959. Please, almost all "mainstream" representations of relativity are still quite inaccurate today.

 

 

In any case, the truth is, for the most part I have only ever thought of relativity as some sort of abstract set of transformations that are preformed on moving objects and never really took the time to understand it differently, now I am starting to see that this is perhaps the worst way and least interesting way of looking at it.

 

 Yeah there are quite many ways to view it, and the most common mistake people make is they lose the perspective on the fact that these effects are a consequence of a very specific coordinate transformation scheme. Usually people represent these effects as "real physical effects" that the observers themselves undergo, but at the same time the observer undergo these "effects" only because we arbitrarily choose to represent that observer in some particular coordinate system.

 

Fundamentally it really has to do with epistemological self-consistency of our definitions. If our definitions are not self-consistent, all kinds of paradoxical effects can arise in our expectations (different ways to represent the same things can yield different observable expectations). The very opening of the paper of SR refers to exactly that kind of paradox.

 

 

After reading this several times one of my first thoughts that came to my mind is the words “So What?”, if both observers use the same length for the ship, and they make their measurements in the y,z directions of the ship moving in the x direction, then of course they will come to the same distance to the star. But this says nothing about how far that they will say that the star is in there reference frame.

 

Well if they happen to use relativistic convention, then they would not have chosen a reference frame apart from their own. So, if they both take themselves as not moving, and they both measure the same distance to the star, then that is exactly the distance they take as "real". 

 

 

However after some thought on the matter I have to come to the conclusion that if we disregarded the effect that the adoration of light has then of course both observers must say that the star is the same distance away as long as both do it in the same way. Otherwise we can distinguish the reference frames.

 

Now this at first seemed to me to be a rather fictitious situation as how can we just ignorer the adoration effects, however after reading about Terrel rotation I have come to the conclusion that this is the case, no matter how we preform the experiment both observers must say that the star is the same

distance away.

 

Yes and if you view earlier post from me you can see I am commenting on this very issue. The thing is, they must calculate the relative speed between themselves and the star of interest, and calculate a compensation for the aberration at that relative speed. Basically they take the perspective of the emitter to calculate away any given aberration. If they don't, they can't really navigate at relativistic speeds, because at some point pretty much the whole universe appears to be in front of them no matter what they do.

 

Or to say it other way around, if they don't compensate for this effect, they are always navigating to a location where each star was in their coordinate system, "when the light was emitted", so to speak.

 

In general, it is useful to view relativity from the point of view of "what can be known", when you have finite information speeds. It defines your simultaneity, it defines the behavior of your time measurement devices, and it defines your length measurements, and you need to establish some conventions to yield any kind of self-consistent set of definitions for all of these.

 

-Anssi

[Doctordick]

When I was nine years old, I read a book by George Gamow called "One Two Three ... Infinity". My father had purchased the book not long after his discharge from service in WWII. I am quite sure the purchase was triggered by the a-bomb dropped on Japan. In any event, it was essentially a presentation of relativity for the uneducated. My dad read it but I suspect now that he really didn't understand it. It was in the house and, out of curiosity, I read the thing myself. I am sure that most everything in that book went well over my head; however, it nevertheless had a rather important impact on my thinking.

First of all, I was totally ignorant of Newton's mechanics and the mathematics involved so anything related to those factors went totally over my head. Secondly, to me the three dimensions of reality were up/down, right/left and forward/back; essentially Euclidean geometry though, at the time, I knew absolutely nothing of the subject. Those three concepts covered what little comprehension of geometry I understood. Most everything else essentially went in one ear and out the other (so to speak). However, there was one description of an experiment which I remember quite clearly. It was the measurement of the speed of light by two different people. One was on a train moving at a high speed and the other was on the ground next to the track.

What Gamow brought up was the fact that the two observers would disagree as to the correct time of two events very important to measuring the speed of light. In order to know the speed of light you need to know two numbers: the time difference between the start and finish and the distance covered during that time. That fact I understood.

 

At the age of nine (and actually until I got to college), my concept of time was quite simple: two things at the same place at the same time can interact. If they don't exist at the same time they cannot interact. I would like to point out that this is essentially the fundamental idea behind the ordinary concept of time held by most everyone. The idea that establishing the time of events separated by some distance was a subtle problem absolutely never occurred to me prior to reading Gamow and probably occurs to few people even today.

 

Gamow pointed out that the apparent time, as seen, between events separated by any distance have to be corrected by the length of time it takes the light to reach one's eyes. The two observers essentially had to conceptually set up two clocks separated by the length of the path of the light over which the velocity was to be measured. If they presumed the other party was moving and they were standing still (which is the central issue behind the concept of "relativity"), they would both presume the lights velocity in both directions was the same and end up disagreeing as to the settings on each others clocks. The subtle issue is that understanding what happens when one actually moves a physical clock involves understanding those relativistic effects Gamow was explaining.

Clearly I had utterly no concept of the coordinate system he was setting up and, as a consequence, my immediate reaction was: "Oh, you can't use clocks to set the time!" In a sense, my ignorance was a direct consequence of the fact that I had utterly no comprehension of Newton's space-time diagrams of dynamic systems. I thought the interactions themselves defined the time.

 

At any rate, Gamow went on to suggest that "time" was actually a fourth axis orthogonal to the three space dimensions - up/down, right/left and forward/back. Thus, in my head Gamow's four dimensions were - up/down, right/left, forward/back and one more: "before/after". As far as I understood it at the time, these were all real directions. I had utterly no concept of what mathematicians call "imaginary" numbers. Such a thing was totally outside my comprehension and, in my mind, Gamow use of the word "imaginary" simply meant I couldn't actually examine this fourth dimension though it supposedly existed nonetheless. A rather simple minded presumption.

Now I don't know when I first heard of Plato's “shadows on the wall” (see http://en.wikipedia.org/wiki/Allegory_of_the_Cave) but it was probably from my father as he was to only person I knew who tended to read stuff like that. Nonetheless, the idea which popped directly into my mind on reading "One Two Three ... Infinity" was that this "imaginary fourth dimension" could not be seen because it was projected out: i.e., the three dimensional world we found ourselves in was essentially Plato's "shadows on the wall". I was aware of Plato's idea when I read Gamow's book and pretty well understood "projections" as, when I was a child, we commonly created shadows of dogs, butterflies and other things with our hands.

By this means I had a rather simple mental image of the phenomena Gamow was talking about. The universe consisted of things in a four dimensional universe where the fourth dimension called "time" (essentially what was measured by clocks) was being projected out. Of course, this picture was totally Euclidean as any other geometry was simply beyond my comprehension.

So, let's look at some of the details of a universe represented by such a mental image. In particular, note the consequences of things moving in the direction of that fourth axis "time'. If everything in that four dimensional universe is at rest, and that fourth axis is simply projected out, everything in the projection will also appear to be at rest. If interactions occur when two objects occupy the same space at the same time in that four dimensional space, since fourth dimension is being projected out, those objects will also appear to occupy the same space at the same time in the "shadow universe".

 

If we add motion to this picture, objects can then move and interact in that four dimensional universe. We also end up with objects moving and interacting in the "shadow universe". The first question which arises is: in this picture, what is light? In Gamow's description of Einstein's theory of relativity, clocks ran slower in the moving train and, at the speed of light, they changed not at all. To my child's mind, this clearly implied light was not moving in the "before/after" direction; not if clocks measured change in time.

 

My conclusion was that when objects moved in the four dimensional universe they were covering less distance in Gamow's "time" direction. When at rest, they clearly covered the maximum distance in the time direction. Since Gamow's "time" dimension was what clocks measured, and not the actual movement in that dimension, it seemed very reasonable that the actual distance being covered in that four dimensional universe during any specified time was the same. The distance they covered in Gamow's "time" direction was simply being projected out.

 

A little thought suggests that if "c" were the speed anything moved in that four dimensional universe, the speed of light will have to appear to be "c" in the shadow universe. Furthermore, if an object is moving in the "before/after" direction only, no matter what its velocity happens to be, it will appear to be at rest in the "shadow universe" we see. Thus since motion in the time direction is not a measurable thing it is perfectly reasonable that everything is moving at the same speed in the four dimensional universe.  It thus becomes quite clear that, if everything is moving at exactly “c” in the four dimensional universe, all of the measurements taken in the shadow universe turn out to be exactly as Gamow presented them.

For that reason, as a child, I thought that I understood Einstein's relativity. I even tried to explain it to my classmates but found they had little interest in the issue. In actual fact, I didn't find out that I was in error until I got into College. (Back in my day, relativity wasn't even discussed in high school physics.) When I was in college, I discovered that Einstein's theory of special relativity had absolutely nothing to do with the mental model I had created in my head and I learned exactly how his theory of special relativity worked.

 

What I found rather interesting was the fact that my Euclidean mental construct seemed to always give exactly the same answers as his theory. Actual calculations were sometimes easier in his picture and sometimes easier in my picture so, whenever I took a test, I used the mental construct which was more convenient to the specific question being asked. Not once in my entire life did my picture ever give me an incorrect answer. Nevertheless, since Einstein was the authority, I presumed my picture was erroneous. Clearly, Einstein's theory included nothing analogous to that projection I had dreamed up and I could conceive of no mechanism to justify such a projection.

As I learned more physics, that projection mechanism really began to bother me. Even though it seemed to work so well, I found it impossible to justify such a projection. It certainly was not light as light was a phenomena in the shadow universe. By the time I graduated from college I was rather astonished by the fact that both pictures always gave exactly the same answers. Nonetheless, I never brought the issue up because I was convinced the picture had to be erroneous. On the other hand, I continued to use it because it was often so much simpler to use than Einstein's picture and, it was no big thing if it did give the wrong answer as I could then use that fact to understand the difficulty with my picture.

The first year I was in graduate school, I learned about quantum mechanics (back in my day, quantum mechanics was not taught in physics at most liberal arts colleges). It was in my first class in quantum mechanics when I learned of the uncertainty between position and momentum; the fundamental Heisenberg uncertainty principal. Astonished, I immediately realized that, if mass were momentum in that "before/after" direction, quantization of mass would have to yield infinite uncertainty of position in that direction. Moreover, we live in a universe where most all entities of interest are mass quantized. It followed directly that this certainly was a mechanism which would provide that projection I had been using for twenty years. After a little work, I managed to prove the two mental constructs were actually mathematically identical.

The next day I showed my proof to the professor teaching that quantum course and after about four hours of persuasion, he finally admitted that my proof was correct. I remember to this day his exact words: "Yes, you are correct but please do not show this to any of the other students as it will just confuse them!" So I took his direction as important as Einstein was the authority and I never did show it to any of the other students.

Later on, when I began to study general relativity, I realized that ordinary Euclidean transformations, which were much easier than Einstein's mathematics, could be applied to events in my four dimensional universe. However, the observable results in the shadow universe yielded answers somewhat different from Einstein's general theory of relativity so, though I still thought about the thing quite a little, I tended to regard it as definitely erroneous. You know, we all tend to trust authority (they wouldn't assert things unless they had pretty good evidence; at least one would think).

 

Well, the rest of my graduate studies were rather disappointing. I had gone into theoretical physics because I wanted to understand reality and physics seemed to more rational than other fields. Most physicists would either answer a question I posed or suggest I would have to deal with more educated people then themselves. In graduate school this behavior seemed to vanish.

 

In graduate school I discovered that experimentalists did experiments to check the numbers the theorists gave them (exactly what I had expected) and that theorists calculated numbers on the assumption the theories were correct (which was not what I had expected). I never met a theorist who seriously worried about errors in their theories. In fact, I once asked my thesis adviser a question and his response rather surprised me. He said, "only geniuses ask questions like that and believe me you're no genius!" He then turned around and walked away.

 

After considerable thought I came to the conclusion that "genius" is a name tag professionals give to presumed crackpots who turn out to be right. It seemed to serve little purpose beyond being an excuse for not recognizing the problem issue themselves. It seems to me that the theoretical side of physics is a "by guess and by golly" approach. Someone guesses a solution to the problem they see and then investigate the expected experimental results. If the results turn out to agree with their solution, the opinion will be, "by golly they must be right".

 

I officially received my Ph.D. from Vanderbilt University in January of 1971 for performing a theoretical calculation of a scattering problem of interest to the experimental staff at Oak Ridge National Laboratory.

 

But back to my thoughts on understanding reality. By 1970 I had deduced what I call my "fundamental equation". That detailed deduction may be found carefully laid out in chapter two of "The Foundations of Physical Reality" see http://foundationsofphysics.blogspot.com/. In that chapter, it is specifically proved that absolutely all internally consistent explanations of any collection of information can be seen as constrained to obey that equation (that is why I call it "fundamental"). It was a nice proof but unless solutions to that equation can be found, it is really a rather mundane issue.

 

During the late seventies I made some serious attempts to solve that equation and even consulted with some theoretical physicists on the issue. Being what is called "a many body problem", it is well known to have no general solutions. Nevertheless, sometime in the early eighties, I found an interesting approximate solution by making some rather extensive assumptions. Once I had that, I managed to discover a number of various assumptions which led to other interesting solutions.

 

At that point, I decided that the thing ought to be published. That attempt to publish was a fun experience. In 1982 I created a paper expounding on my discovery (what I have come now to call the first edition). I submitted it to three different physics journals, all of whom rejected it out of hand. I don't think a referee ever saw the thing as the rejection was to quick to allow time for anyone to seriously read it. I suspect the real problem was that they didn't have any idea as to who's area it belonged in. All three said it was philosophy and of no interest to the physics community.

 

So I went to my thesis adviser to see about getting a little help getting the thing published. His response surprised me. He refused to even look at what I had written and merely said, "No one will ever read your stuff Stafford; because you haven't paid your dues!" Over time I realized he was right. I once submitted my paper to some philosophy journals to see if they would publish it and got the rejection “this isn't philosophy, it's mathematics”. When I asked some mathematicians about the issue they said, “there is no new math in here; this is physics not mathematics. So it seems I have discovered something no one is interested in.

 

As an aside, I would like to point out that it is a well known fact (by all modern scientists) that Einstein's "theory of relativity" is patently inconsistent with quantum mechanics (an issue no one seems to take seriously) whereas my presentation (just given here is one hundred percent consistent with quantum mechanics and, in addition, gives exactly the same results as special relativity.

 

Now, in the case of Einstein's "general theory of relativity" it gives somewhat different answers; however, those differences are rather interesting and perhaps remove some problems in modern physics.  They are covered in detail in my book.

 

Have fun -- Dick

Edited May 26, 2014 by Doctordick

[AnssiH]

DD's book mentioned above can be read online now, see links via; http://foundationsofphysics.blogspot.com/

 

-Anssi

Edited June 7, 2014 by AnssiH

[Bombadil]

I'm sure there were individuals over the years who figured it out without giving the effect any name, but the fact remains that most people just are not interested of thinking. They just accept what they hare from their chosen authority. So on the web pages I goggled they are saying many representations of relativity were incorrect up until 1959. Please, almost all "mainstream" representations of relativity are still quite inaccurate today.

 

 

If by main stream you mean the ones that everyone follows that just wants to know something about the topic so that they can say that they know something about it, then I would agree with you. I think that the real issue is though, that most people just want to be able to make up their own theories and say that they know better then the experts, or at least as much, or they want to say that they understand string theory or supper symmetry or whatever the latest theory is. I actually have no idea what the latest theory is and I really don't have any need to look up what it is as I would rather spend nine hours trying to accurately understand classical Hamiltonian mechanics or special relativity (something that I feel that I can accurately understand at this point) then spend an hour listening to Michio Kaku, someone that if I can stand listening to for 10 minuets then I feel like I have a full dose of something for at least the next month and it is not an understanding of physics.

 

I think that the real problem is that rather then present things in an accurate form, things are presented in an overly simplistic form without telling anyone that it is overly simplified.

 

 

 

  Yeah there are quite many ways to view it, and the most common mistake people make is they lose the perspective on the fact that these effects are a consequence of a very specific coordinate transformation scheme. Usually people represent these effects as "real physical effects" that the observers themselves undergo, but at the same time the observer undergo these "effects" only because we arbitrarily choose to represent that observer in some particular coordinate system.

 

 

The prospective of viewing it as a coordinate transformation can be taken too far as well, just think about it, if we view it as purely a coordinate transformation then we will lose track of the fact that this all has to do with a finite speed of light and will start looking at it as nothing more then a mathematical definition. Which isn't necessarily a bad thing as long as we don't lose track of where it started.

 

I think that viewing it as a coordinate transformation and trying to explain what it means to transform coordinates will only result in expecting things to appear shorter in different coordinate systems. Just think about trying to explain to the average person what it means to change coordinates and then try to explain that the Lorenz transformation is just a coordinate transformation. For that matter I wonder how many people realize that the Lorenz transformation is really a mathematical equation or at least would recognize the Lorenz transformation if they saw it.

 Yes and if you view earlier post from me you can see I am commenting on this very issue. The thing is, they must calculate the relative speed between themselves and the star of interest, and calculate a compensation for the aberration at that relative speed. Basically they take the perspective of the emitter to calculate away any given aberration. If they don't, they can't really navigate at relativistic speeds, because at some point pretty much the whole universe appears to be in front of them no matter what they do.

 

 

I don't think that I follow unless you are saying that they are traveling so fast that they can't see the universe around them and all that they can see is ether directly ahead or behind them. Don't forget that the length of any object is still the same as seen by the moving observer, and so since they still see everything from a moving frame the same way they would from a rest frame the result is that they see the same universe whether they are moving or stationary with respect to the rest of the universe.

 

Actually I would be rather interested at this point in seeing a worked out set of equations for observed speed between two observers, not the speed in that relativistic coordinate system where every thing contracts but what is actually observed, I suspect that it may be very different from what the scientists say it looks like. Actually I am half way tempted to try and work them out myself if I can just find a few extra minuets, I am wondering what you would expect the result to be though.

 

At the age of nine (and actually until I got to college), my concept of time was quite simple: two things at the same place at the same time can interact. If they don't exist at the same time they cannot interact. I would like to point out that this is essentially the fundamental idea behind the ordinary concept of time held by most everyone. The idea that establishing the time of events separated by some distance was a subtle problem absolutely never occurred to me prior to reading Gamow and probably occurs to few people even today.

 

 

My first thought is, isn't this the definition of at the same time, that is if two objects interact they must be at the same place at the same time just as you say, and I would have to agree with this definition.

 

However on consideration, this is not what relativity would seem to be based on, rather relativity would seem to be based on the idea that time at any point is what a clock at that point reads. Then relativity seems to go about defining a means of transforming between different clocks.

 

So do physicists take this to the next step and never define a single coordinate to describe their systems in and rather keep transforming back and forth between whatever system they find interesting or convenient at the time?

 

 

So, let's look at some of the details of a universe represented by such a mental image. In particular, note the consequences of things moving in the direction of that fourth axis "time'. If everything in that four dimensional universe is at rest, and that fourth axis is simply projected out, everything in the projection will also appear to be at rest. If interactions occur when two objects occupy the same space at the same time in that four dimensional space, since fourth dimension is being projected out, those objects will also appear to occupy the same space at the same time in the "shadow universe".

 

 

Are you using that fourth axis that is being projected out as time, if so isn't the distance moved along that axis exactly what clocks are going to measure? I thought that the definition of time that you were using would be just a parameter used to define the evolution of the system and independent of movement along that 4th axis?

 

Also what is to stop two objects from having their projections passing though each other due to them missing each other in that fourth dimension, can this this be seen as a result of the uncertainty that you use to create the projection?

 

A little thought suggests that if "c" were the speed anything moved in that four dimensional universe, the speed of light will have to appear to be "c" in the shadow universe. Furthermore, if an object is moving in the "before/after" direction only, no matter what its velocity happens to be, it will appear to be at rest in the "shadow universe" we see. Thus since motion in the time direction is not a measurable thing it is perfectly reasonable that everything is moving at the same speed in the four dimensional universe.  It thus becomes quite clear that, if everything is moving at exactly “c” in the four dimensional universe, all of the measurements taken in the shadow universe turn out to be exactly as Gamow presented them.

 

 

Have you ever come up with a mechanism that would ensure that nothing can travel at a speed other then c in such a view, or do you think that such a thing would only serve the purpose of confusing the mental image, or do you think that this really is nothing more then a consequence of what the model is representing without any analog in the model?

 

I will stop there for now and see what your response is.

[AnssiH]

The prospective of viewing it as a coordinate transformation can be taken too far as well, just think about it, if we view it as purely a coordinate transformation then we will lose track of the fact that this all has to do with a finite speed of light and will start looking at it as nothing more then a mathematical definition. Which isn't necessarily a bad thing as long as we don't lose track of where it started.

 

I think it would be only a good thing if people understood better that all of our object definitions, time definitions and space definitions are based on observable state changes of some sort (by which I just mean to be neutral about what stands behind observable things), and it is the necessity of creating self-consistent set of definitions that leads into things like relativistic time relationships.

 

People just tend to attach meta-physical concepts to their explanations without realizing how redundant those concepts are. Relativistic spacetime for instance is basically Minkowski's meta-physical explanation for special relativity, not actually required by the theory. The theory arises directly from Maxwell's definitions of electromagnetism, in so far that those definitions are correct, and one wants to express them in different inertial frames self-consistently.

 

People tend to view time as a meta-physical thing as well, as in something that just flows steadily onwards, and assume that progression is what we obsere in our everyday life. But actually any physical definition of time must always be associated with some observable state changes, and there is no sense in which those state changes are evolving "fast" or "slowly" in themselves. If we define a time measurement of something, we define a way to count the number of state changes and compare it to some other state changes.

 

If you define a clock as a physical object (as oppose to meta-physical one), i.e. when you actually model the internal processes, you will run into circular reasoning very fast because we cannot possibly know how those processes are evolving "in time" without making assumptions or conventions about things we cannot possibly measure.

 

I just recently saw some article about a new experiment to measure the one-way speed of light, and in that experiment they found it to be exactly "C", via using relativistic convention to synchronize their clocks...

 

That is *exactly* the same thing as running an experiment about whether or not water flows downhill, and as a first step using the flowing direction of water as to establish what is to be considered "downhill".

 

The existence of those kinds of experiments implies that a lot of people have lost perspective on this thing.

 

I don't think that I follow unless you are saying that they are traveling so fast that they can't see the universe around them and all that they can see is ether directly ahead or behind them.

 

Yeah, consider that pretty much the entire observable universe is almost perfectly stationary relative to itself (which btw is completely unexplained feature of the universe as far as I know), and when you are moving close to C in relation to the rest of the universe, the entire universe appears to be almost directly in front of you (all the light from the rest of the universe is coming into the ship in extreme angle). Edited July 13, 2014 by AnssiH

[Doctordick]

Response to Bombadil's post of 19 June 2014.

 

However on consideration, this is not what relativity would seem to be based on, rather relativity would seem to be based on the idea that time at any point is what a clock at that point reads. Then relativity seems to go about defining a means of transforming between different clocks.

The first thing you must comprehend is the fact that clock readings do not correspond with “time”. They are essentially a coordinate Newton introduced in order to plot movements of entities in his physics. What you need to take into account is the fact that two clocks reading the same value does not at all indicate that they exist at the same time. In fact all the satellites used in the modern mapping applications work off different clocks none of which are guaranteed to read the same. Relativistic corrections have to be made in order to specify the coordinates of the referenced objects at a specific time.

 

Anyone who knows anything about modern clocks knows that the standard clocks used to define the time based in Colorado disagree if they are moved from one floor to another higher or lower.

 

Physicists set up Newtonian coordinate systems convenient to their calculations. In these Newtonian coordinate systems, the reference clocks are at rest.

 

Are you using that fourth axis that is being projected out as time, if so isn't the distance moved along that axis exactly what clocks are going to measure?

Yes it is!!!

 

I thought that the definition of time that you were using would be just a parameter used to define the evolution of the system and independent of movement along that 4th axis?

Yes that is correct; except for that comment, “independent of movement along that 4th axis”. What we call time is that parameter you just spoke of but it is clearly not what clocks measure. Clocks only measure changes parallel to the time axis! As used in the relativistic calculations the proper time coordinate is only specified by a rest clock (one which is not moving orthogonal to the time axis.

 

Also what is to stop two objects from having their projections passing though each other due to them missing each other in that fourth dimension, can this this be seen as a result of the uncertainty that you use to create the projection?

If that fourth dimension is time then being at the same (x,y,z) position at a different time means they cannot interact. Since that time axis is projected out by uncertainty, the only means of knowing they exist at the same time is the fact that they interact.

 

Have you ever come up with a mechanism that would ensure that nothing can travel at a speed other then c in such a view, or do you think that such a thing would only serve the purpose of confusing the mental image, or do you think that this really is nothing more then a consequence of what the model is representing without any analog in the model?

 

In my shadow picture, every point in the universe follows some path through this four dimensional space. Movement along this path defines time (not what clocks read). Light is clearly moving perpendicular to that “time” axis (a clock moving with a photon shows no change in time along the path). Any object moving parallel to the “time” axis will appear to be at rest in the shadow universe no matter what its velocity might be. In fact its velocity is not a measurable thing. The simplest view is that the velocity of a point has nothing to do with which way it is going; it is no more than a measure of its movement along its path over time and setting it to “c” is no more than setting the measurements of that time axis to the same units used on the other three axes.

Edited July 18, 2014 by Doctordick

[Doctordick]

Well, I have been thinking about the issue central to this discussion: exactly how does the universe appear when observed from a interstellar ship moving at an extreme relativistic velocity. The general consensus put forth in this thread is totally invalid and I think I have a simple way to show all of you what the correct answer is.

First of all, the relativistic conversion between two coordinate systems moving at a velocity v in the x direction with respect to one another is as follows: y'=y , z'=z ,

[math]x'=\frac{1}{\sqrt{1-\left(\frac{v}{c}\right)^2}}[x-vt][/math]

and

[math]t'=\frac{1}{\sqrt{1-\left(\frac{v}{c}\right)^2}}\left[t-\frac{vx}{c^2}\right].[/math]

These conversions are perfectly symmetric: i.e., changing the formulas to the reverse conversion is a simple matter of changing the primed coordinates to unprimed and vice versa together with a change in sign of v. It should be clear to everyone that who is moving and who is at rest is no more than the perspective of the observer.

What is critically important is that these representations do not represent what will be seen but is rather a representation of the dynamic system as represented in the space time coordinate system Newton invented to display the dynamics of his physics. In order to make that issue clear, let me point out that when one looks at the stars, one does not see them as where they are now (what Newton's coordinate system is designed to display) but rather where they were some time ago.

In essence the conversions given above do not convert what one observer sees to what the moving observer sees (or vice versa). Converting one appearance to the other is not a simple matter and making sure you get all the subtle factors correct is close to impossible. Because of that issue, I will give you an example which I think most people here can comprehend.

Consider a hypothetical mechanism which is capable of changing the velocity of the entire solar system by some fixed factor without changing the appearance of the dynamic system in any way: i.e., our ship will consist of the entire solar system and the design of the ship is such that what we see internal to the ship is exactly what we see now. Let this mechanism add 0.999999c in some specific direction to every element making up the solar system.

The question then is, “What does the rest of the universe look like to us?”

The critical factor is the fact that what has just been described is identical to leaving the solar system as it is and instead adding 0.999999c in the opposite direction to every element in the rest of the universe. So let us look at the consequence of that act.

The speed of light is roughly 186,000 miles per second. It follows that the velocity added to every element in the rest of the universe would be be roughly 185,999.91 miles per second, pretty well a relativistic velocity in any analysis.

The nearest star, Proxima Centauri, is roughly 4.2 light years away from the solar system. Converting to miles that would be roughly 132,538,291 miles away. Every second, the sine of the angle to the stars position as seen from the earth would change about by 0.0014 or about 0.08 degrees. In about twelve minutes it would have moved almost 45 degrees. Now that is pretty fast motion but it doesn't constitute the kind of distortions proposed in this thread.

The farthest stars are presumed to be about 14 billion light years away. Set a typical star as something like 8.4 billion light years away (I just pulled that out of my hat). That would reduce the apparent angular shift by a factor of two billion. The number of seconds in a year is 31,556,736 so in an entire year would only generate a shift of less than 2.5 thousandths of a degree. That implies one would have to observe it for over several lifetimes before seeing an apparent shift of one degree.

So, for the most part, the universe would look pretty much as it did when we were at rest.

Anyone have any arguments with that presentation?

Have fun -- Dick