Relativity And Simple Algebra

[Moronium]

Let's go back to the question you raised about two planes circling the earth in the same direction versus them flying in opposite directions.  It was a good point.

 

Per SR, they would have vastly different relative speeds (and hence vastly different amount of time dilation) depending on which way they were going, but that makes no real sense.

 

Why doesn't it make sense?  Because SR says time dilation is due to relative speed, not absolute speed.  But it isn't due to relative speed, which is what the H-K experiment proved.  It is due to absolute speed, not relative speed.

Edited February 22, 2019 by Moronium

[ralfcis]

It's tricky here, there are actually two issues. You must recognize that an orbit is basically the same as the twin paradox and not just reciprocal time dilation. When you draw the twin pardox as twins separating and then re-uniting, the numbers work out to the same age diff between them as if they flew along side one another. I got confused when I said my STD showed that relative velocity should be the same whether the twins separate at .33c or one stays on earth and the other goes out at .6c. I mistakenly assumed the earth frame would be the same in both depictions and equivalence of all relative velocities would remain equivalent. This was not true. The earth frame is stationary when the twins separate at .33c but the earth frame must be at .33c relative to whatever the cartesian coordinates represent when one stays with those coordinates and the other takes off at .6c relative to those coordinates. This would be like assuming the earth clock would have to move for the HK example where the planes take off in opposite directions. It does not because it is an example of age difference not reciprocal time dilation as it is in the conversion of the Loedel STD to the Minkowski depiction. 

 

I feel you will not understand a word of what I just said, ignore it all and continue with the way you interpreted it anyway.

[Moronium]

 

 I mistakenly assumed the earth frame would be the same in both depictions and equivalence of all relative velocities would remain equivalent. This was not true. The earth frame is stationary when the twins separate at .33c but the earth frame must be at .33c relative to whatever the cartesian coordinates represent when one stays with those coordinates and the other takes off at .6c relative to those coordinates. 

 

 

Forget the STD.  The best way to look at the twin paradox is to assume that the earth twin is motionless (relative to his twin, anyway) and that it is ONLY the travelling twin moving.  Which comports with common sense.  In that way, it's clear whose clock (aging) is slowing down--the space twin's (moving clocks run slow).

 

And that is absolute motion, not relative motion.  The earth serves as the preferred frame in this example, and the time dilation is not reciprocal.

 

And that's the way it works out in SR, too, even though SR is supposed to forbid the use of a preferred frame.  The only reason a "paradox" arises in SR is because the traveling twin is forced to (falsely) assume that he is at rest when he aint.

 

Edited February 22, 2019 by Moronium

[Moronium]

Forget the STD.  

 

 

You can plot all that on an STD, too.  The trick is to ignore what the "other guy" (space twin) sees or thinks.  It's all incorrect.  What the earth twin sees is what is correct.

[Moronium]

The best way to look at the twin paradox is to assume that the earth twin is motionless (relative to his twin, anyway) and that it is ONLY the travelling twin moving.  Which comports with common sense.  

 

 

 

I might add that's it's not just common sense.  It's part of the hypothetical from the get-go.  You are told that one twin blasts off into space, goes a long way, then returns.  Obviously he is moving all that time, not at rest. Likewise, we are specifically told that the earth twin goes nowhere (doesn't move, and hence is "at rest").

Edited February 22, 2019 by Moronium

[ralfcis]

Preaching again. You're wrong. Do you have a question because if you don't want to learn anything I'll just put you on ignore and then you won't be able to ask a question I'll see.

 

PS. I'm going to put some more people on ignore and I encourage everyone to do so to self-regulate the forum against trolls. If they're not seen, they cease to exist.

Edited February 22, 2019 by ralfcis

[OceanBreeze]

Oh no, now I'm back to being confused again.

 

 

 

You are not the only one! But at least you know you are confused; that is a healthy sign.

 

 

Ok, here's where I'm confused. 2 ships are leaving earth at .8 c relative to earth in opposite directions, the relative velocity between the two ships is .9756c, not 1.6 c. The 3rd party observer on the earth  would measure each ship at a relative velocity to him at .8c. He can't get a radar gun reading from one ship to another but he can get a televised picture of what one ship sees of the other. He can see from the images,  the doppler shift ratio confirms their relative velocity is .9756c But he would also see the space between them is growing at 1.6c from his perspective. The ships are going in a line away from him which defines relative velocity to him. But if they were just comets streaking across the sky parallel to him there would be no relative velocity even though they streak across the entire length of his horizon.  The space is also expanding in a line parallel to him so it's expanding at 0 relative velocity to him so the speed of expansion is unrelated to him. So if you're looking at light from the side, you're looking at it's non-relative velocity (speed) and when you're looking at it head on, it becomes a relative velocity.

 

 

That all seems correct to me.

 

But is does have a specific direction, sideways. Without that specific direction, it would be a relative velocity.

 

 

 

 

Well, my language was probably not precise enough so your confusion is at least partly my fault.

 

I will try to explain better, but this will be a bit long.

 

Sideways is not a specific direction.

 

This is a specific direction to the right:   ref----------------------------------------à 0.8c

And it is a velocity vector (velocity is always a vector with both magnitude and direction)

 

This is a specific direction to the left:   0.8c  ß-----------------------------------ref

And it is also a velocity vector

 

This does not have a specific direction:  0.8c ß------------------ref-------------------------à0.8c

 

No single direction with respect to the reference, so it cannot be a vector and therefore not a velocity

 

There are two separate velocities but they cannot be summed in the usual manner to get one single velocity with respect to the reference. But they can be summed in that way to get a closing speed (actually a separation speed in this case) Speed is a scalar quantity.

 

Because this speed is not a velocity, it can exceed c without presenting any problem to SR. There is no single object here that is moving with a relative velocity (with respect to the reference) that is greater than c.

 

If you shift the reference to one side and claim the velocity with respect to the other side is greater than c, that is not just a violation of SR, it is wrong according to how this universe works!

 

Einstein’s velocity addition formula is not some gimmick that Einstein came up with just to mess with everybody’s heads. Maxwell’s equations correctly calculated the speed of light as [math]\frac { 1 }{ \sqrt { \mu \varepsilon  }  }[/math] in a medium with permeability μ, and permittivity ε, but that equation says nothing about any frame of reference!

 

Experiments such as MM found that the speed of light (all em waves) is invariant in any reference frame.

 

According to Einstein, the reason the velocity addition formula is necessary is; that is the way the Universe works! When objects are in motion, the fabric of space and time changes. Time slows down and distances contract. We do not notice this at small everyday velocities because the change is infinitesimally small. But at velocities approaching c, the change becomes very large. Einstein’s velocity addition method is the proper method for adding all velocities, no matter how slow! The way we usually add velocities is only an approximation that is good enough for our everyday needs but it gives incorrect results when the velocities are a significant fraction of c.

 

Although this contradicts our intuitive notion of velocity addition, Einstein’s method yields results that have been confirmed many times over in many different experiments. SR has passed every test it has been subjected to, without fail.

 

It is OK to be skeptical about something that is as non-intuitive as SR, and I have expressed some uncertainties myself. But it doesn’t make much sense to pretend to know better than Einstein and all the physicists who have tested and verified SR. Unless someone is prepared to show where the math is wrong and/or the theory can be experimentally shown to fail, the arguments are really just a waste of time. Maybe we don’t really understand the true nature of time but one thing is certain; time is too valuable to waste.

[ralfcis]

"There are two separate velocities but they cannot be summed in the usual manner to get one single velocity with respect to the reference." So an arc across the sky is a composite summation of relative velocities that probably sums to zero.

 

Thanks. Sideways bad, head-on good.

[Moronium]

Although this contradicts our intuitive notion of velocity addition, Einstein’s method yields results that have been confirmed many times over in many different experiments. SR has passed every test it has been subjected to, without fail.

 

So have alternate theories of relative motion with postulates that are antithetical to SR.  By physicists.  Many times.  In fact every single test that "confirms" SR also confirms those theories.

 

I thought you understood that.  

Edited February 23, 2019 by Moronium

[Moronium]

So have alternate theories of relative motion with postulates that are antithetical to SR.  By physicists.  Many times.  In fact every single test that "confirms" SR also confirms those theories.

 

I thought you understood that.  

 

If there are two theories which explain all the known phenomenon, how do you know which one is right?  You might prefer theory A, I might prefer theory B.  That's fine.  It's something we could discuss, and each give our reasons for preferring one over the other.  But there is no possibility for discussion with close-minded people who say I'm right, and if you disagree with me, you are a science denier.

 

If you shift the reference to one side and claim the velocity with respect to the other side is greater than c, that is not just a violation of SR, it is wrong according to how this universe works!

 

 

You have no scientific basis for making such a declaration.  You're just asserting your quasi-religious faith. 

Edited February 23, 2019 by Moronium

[Moronium]

Same goes for you, Ralf, but I expect that from you.

 

You're wrong. Do you have a question

 

 

 

You refuse to answer questions, such as the one below, so why bother?   As I said, and as was obvious, from the beginning,  you're not hear to "learn" anything, notwithstanding your pretenses to the contrary.   You're here to lecture. You already know it all.

 

So, Ralf, if you assume that A's speed is 0, and if you use E's calculation (whether right or wrong), then A will say that B is moving .975c relative to him.  Using those numbers, what would A calculate the speed between himself and E to be?  I guarantee that it will not be .8c.  Nor will it be .975c/2.

 

 

Since you love math, I'll leave it to you.  I don't care enough to do it myself.

 

Then see what you get from B's perspective (B's speed is 0 and A's speed relative to him is .975c).  Now what does B say E's speed is relative to him?

 

There's a point to this which goes beyond the math.

Edited February 23, 2019 by Moronium

[Moronium]

 

 

t it doesn’t make much sense to pretend to know better than Einstein and all the physicists who have tested and verified SR.

 

So why do you pretend to know better?  As I said before, Einstein himself always acknowledged, as has every theoretical physicist worth his salt since then, up until this very day, that there are competing theories which are perfectly capable of explaining everything just as well as SR.

 

Einstein was a scientist, not a theologian.  He knew better than to proclaim that he was in possession of the TRUTH. 

 

Maybe, just maybe, Einstein and all those other physicists know better than you.  Ever think of that?

Edited February 23, 2019 by Moronium

[ralfcis]

You've been given all the tools to find the answer for yourself. You refuse to use them and if even if you could you would dispute the answer anyway so what's the point? Show some initiative and effort on your part and stop complaining everyone isn't servicing you properly.

 

PS. To me Einstein was a fluke artist. His theory looks wrong based on all the contradictions but just happens to arrive at the right answers. E=mc2 is a perfect example of accidentally predicting the conversion of matter to energy when it was just intended as an explanation of what happens when kinetic energy doesn't cause motion. That idea continues into the explanation of what non-moving acceleration causes (gravity and the twin paradox). Guessing the right answer is not the same as knowing the right answer.

Edited February 23, 2019 by ralfcis

[Moronium]

 

...an explanation of what happens when kinetic energy doesn't cause motion. That idea continues into the explanation of what non-moving acceleration causes (gravity and the twin paradox). Guessing the right answer is not the same as knowing the right answer.

 

1. E=mc2 was derived by Einstein from Maxwell's equations, not SR, and can be derived in a number of other ways which do not rely on SR

 

2.  "non-moving acceleration" is a contradiction in terms, and neither GR nor the twin paradox says otherwise.

 

3.  Kinetic energy never "causes" motion.  It is a property of objects which are in motion, that's all.

 

Take that as a "question" and explain how and why what I said is not the case if you think otherwise.

[ralfcis]

Man you just can't read anything that doesn't fit into what you already believe so what's the point. I'm gonna have to move you onto my ignore list.

[ralfcis]

I forgot to mention a very important result of the STD depicting the train in the station example. It's the same as the pole in the barn example and it disproves the existence of length contraction. Greene covers the example of how relativity allows a pole longer than the barn to fit into the barn when it's going at a sufficient relativistic  velocity from a stationary barn perspective. In several more videos he finally admits the length contraction explanation is a fraud. The real reason is due to the relativity of simultaneity. The clocks on each end of the pole fall out of sync from the barn's time perspective so the front of the pole is actually outside the barn while the back is entering while the pole clocks are saying both ends are in the barn at the same time from the barn's perspective. This is an absolutely true and reasonable explanation that is constantly ignored. Yet relativity pushes the fraudulent length contraction explanation. Both can't be true.

 

Whether you draw the train length contracted (2.5 long for a platform 2.0 long) or not (both 2.0 long) the results will be the same. Both ends will be hit with the light at the same time (1.2) on their clocks but that doesn't mean both ends will be at the barn ends when this happens as is erroneously depicted using length contraction. The front of the train will be just as far outside the platform when the light hits it There is no such thing as length contraction in relativity, there is no physical effect (even Greene admits that) and there is no need for it to explain anything in the math. It's all part of the multiple instances of relativity fraud that people refuse to acknowledge as fraud. Relativity is the Donald Trump of physics theories where you must accept counter-intuitive thinking and suspend critical thinking at the door into the rally. Many people claim what I claim but I have the math to back it up. Unfortunately, no one seems to understand high school algebra anymore.

Edited February 23, 2019 by ralfcis

[ralfcis]

Here's Greene's pole in barn explanation:

 

 

If you use length contraction to explain it, both ends of the pole are physically inside the barn because the pole has length contracted. But if you use the relativity of simultaneity explanation, they are not, even though the pole clocks from the outside perspective say they are. Both interpretations can't be right. Do you believe space physically contracts or do you believe if the clocks say both ends are in the barn simultaneously from the barn perspective, then that is reality (even though you can physically see the two ends are not simultaneously inside the barn (from a god's eye perspective)).

 

Einstein's clock sync method and his assumption that time itself changes due to perspective is what creates the theory of relativity. These assumptions create the counter-intuitive results. Getting rid of the erroneous assumptions does not get rid of relativistic facts, it allows them to be explained intuitively without all the contradictions. All it requires is adopting objective proper time over subjective perspective time. I'll be deriving (now that I've put so many people on ignore) how this concept works using light signals and relative velocity independent  of how it's currently depicted in an STD. There is no need for an absolute preferred frame but there is also no need for choosing which frame is stationary as neither is. There is also no need to assume space moves past anything because a vacuum can't have relative velocity, you can't set a stationary position relative to a featureless vacuum and the energy required to move the universe past whichever participant you choose as stationary is completely unrealistic. These are further crazy assumptions from the theory of relativity.

 

PS. This ignore button is the best thing ever invented for a physics forum. I wouldn't have been banned from so many forums if they had had one. Also, I like the feature that you can go back and edit your posts at any time so long as you're honest about it. This forum is the way all forums should be except for the lack of experts. Oh and another great thing, you can speak your mind and be open to correction without the fear of being cast out for blasphemy. I can see now it was never my fault, it was always the dumb way the other forums were structured. I can finally stop blaming myself.

Edited December 19, 2019 by ralfcis