Relativity And Simple Algebra

[sluggo]

Ralf;

 

Closing speeds are viewed perpendicular to the two things engaged in relative velocity which is a vector. If you go towards a sound wave at 10 mph and the sound wave is going at 750mph, your relative velocity to the sound wave is 760mph. This doesn't mean you have broken the sound barrier.

 

[The person is moving at 10 mph relative to the air. The wave is moving at 750 mph relative to the air. The air gap is shrinking at 760 mph. There is nothing moving at 760 mph. A 2nd person could say, the speed of the wave relative to the 1st person is 760, but that changes the reference point, which is now moving. (the core idea of relativity!)]

 

If you go at 10 mph towards a light wave, your relative velocity to the light wave is c not c+10 and this has nothing to do with closing speed.

 

[A 2nd observer would say the speed of the light relative to you is c+10. Equivalent to, the gap between you and the light is shrinking at the rate of c+10. Light speed is defined as relative to space/vacuum, not relative to an object. Your measurement of the oncoming light would be c, resulting from the effects of your motion.

Relative velocity is the starting distance divided by the time it takes for the two parties to meet.

 

[it's still a case of closing speed, since there are 2 objects moving simultaneously.
Your definition produces a phantom object moving at a phantom speed.]

 

[sluggo]

Ralf;

 

If relative velocity is original distance/ time you get the message, the relative velocity to the message exceeds c just like in the football example. This is not allowed.

 

[Your mental block is, interpreting relative velocity as a real object velocity.
The runner and the football moved at the same speed (as you said), but for only half the time, since the motions were simultaneous. The message arrived earlier, not from anything moving at 10 f/s, but because the distance was reduced for each object. If you don't like closing speed, call it apparent speed.
If Bob drove 60 miles at 60 mph to see Alice, he would see her in 60 min. If he asked her to leave at the same time and drive to meet him, he would see her in 30 min. No one exceeded the speed limit, they only drove half the distance simultaneously.]

[sluggo]

Ralf;

[Your account of the MMX is inaccurate and distorted.]

[Postulate 2 states light speed is constant and independent of its source. Thus you can't add or subtract speed to it. That's not what is happening when using c±v. The problem requires a solution involving light speed and object speed. It's simple, basic algebra, so who here doesn't understand it.]

 

Now why can't you explain your point of view in your own words instead of  having to depend on copying from a book?

 

[i use my own words except in cases where the author's words confirm I'm not injecting my own ideas or misinterpreting theirs. I write my own papers and make my own graphics. Prior to that, I had to learn what the theory contained. I present the material to counter misconceptions. Readers can accept or reject it.]

 

I still believe c is the max speed and information can't travel faster than c but I also believe if you travel towards the light you get the information sooner than someone who doesn't.

 

[Then your belief system has a contradiction. For light, the target is in motion, thus the time varies. Look at your own std. The time forward increases for diverging objects and decreases for converging objects.]

[sluggo]

Ralf;
 

I see now that Einy had to introduce the concept of length contraction so his explanation and assumptions about relativistic facts could be supported. His clock sync method wouldn't work nor should it. It artificially creates a perspective present where all separated clocks share the same superficial readout without sharing a present at all

 

[Einstein questioned anything prefixed with 'absolute'. With his detailed analysis, he showed length measurement required simultaneity, which is not absolute but varies with speed.
From his lecture at Leiden, 1920:
"For if K be a system of coordinates relatively to which the Lorentzian ether is at rest, the Maxwell-Lorentz equations are valid primarily with reference to K. But by the special theory of relativity the same equations without any change of meaning also hold in relation to any new system of co-ordinates K' which is moving in uniform translation relatively to K. Now comes the anxious question:- Why must I in the theory distinguish the K system above all K' systems, which are physically equivalent to it in all respects, by assuming that the ether is at rest relatively to the K system? For the theoretician such an asymmetry in the theoretical structure, with no corresponding asymmetry in the system of experience, is intolerable."
He questioned everything, and removed assumptions when found. Somewhat anti establishment and definitely not politically correct.

There is no conspiracy or manipulation in forming relativity theory. You just don't understand it.]

[ralfcis]

"If Bob drove 60 miles at 60 mph to see Alice, he would see her in 60 min. If he asked her to leave at the same time and drive to meet him, he would see her in 30 min. No one exceeded the speed limit, they only drove half the distance simultaneously.]"

 

But the relative velocity would be 120 mph. Alice's car is going 60 mph towards Bob. Bob's car is going 60 mph towards Alice. No one is exceeding the speed limit but their relative velocity is 120 mph. The gap between them is also closing at 120 mph which a person on the side of the road witnesses. The closing speed equals the relative velocity except for an insignificant relativistic effect. But with higher relativistic effect, the closing speed gets up to two times the relative velocity. Bob and Alice could  see their relative velocity is also 120mph with radar guns. I just don't see how two cars headed towards each other wouldn't crash at twice the speed as one would being parked and the other hitting him at 60mph. That's how head on collisions work. If what you're saying is true then we live in 2 different physical universes.

[ralfcis]

"Postulate 2 states light speed is constant and independent of its source. Thus you can't add or subtract speed to it. "

 

That has absolutely nothing to do with this topic. Sound speed is also independent of its source. The question we're dealing with is the speed independent of the receiver's speed. Sound speed isn't, light speed is. The reason is you can have a relative velocity to the sound's medium where you can't to the light's medium. The train rear is a receiver so why are you mixing that topic with source speed which has nothing to do with that discussion. Can you not see this?

[ralfcis]

"[Then your belief system has a contradiction. For light, the target is in motion, thus the time varies. Look at your own std. The time forward increases for diverging objects and decreases for converging objects.]"

 

Time from which perspective? If I use proper time perspective the light hits the train rear at the same proper time and different times from different perspectives. You have missed the point on everything professor.

Edited December 21, 2019 by ralfcis

[ralfcis]

If you use a stopwatch to measure length and the time your watch measures to an outside observer is affected by motion then you're measurement will be likewise affected. It doesn't mean the length itself will be affected, only the measurement of it.

 

You are confusing the length of an object with the distance an object is away from an event. The half train in my example is 1 ly long but the distance it is from where the light is triggered depends on the perspective you choose (and you have 3 choices not just 2). So when I say the mid train triggers the light at mid platform I'm not talking about the length of the train, I'm talking about how the train distance from the event at mid platform will affect how all subsequent time measurements will be affected. By using Einy's method, the train half does not start out 1.5625 ly long from the platform's perspective, it is .9357 platform yrs from the event at mid platform which is set to 0 from the train's perspective.

 

The only person that doesn't understand is you. You refuse to look at my math or even my words. You don't read them because you assume I'm saying something other than what I'm writing. You still don't know what proper time is and assume I'm misinterpreting what perspective time is. There is no point in continuing our discussion until you make some sort of effort to hear and acknowledge what I'm saying.

Edited December 21, 2019 by ralfcis

[ralfcis]

We're miles apart on our definitions of terms and understanding. The only person on this forum who could possibly settle our differences is Popeye. At least I'd consider what he had to say because I mostly have agreed with him whereas the opposite is true for everyone else here.

Edited July 7, 2019 by ralfcis

[marcospolo]

"Postulate 2 states light speed is constant and independent of its source. Thus you can't add or subtract speed to it. "

 

That has absolutely nothing to do with this topic. Sound speed is also independent of its source. The question we're dealing with is the speed independent of the receiver's speed. Sound speed isn't, light speed is. The reason is you can have a relative velocity to the sound's medium where you can't to the light's medium. The train rear is a receiver so why are you mixing that topic with source speed which has nothing to do with that discussion. Can you not see this?

Prove or even explain how light speed is independant to the reciever's speed.

 

Sound speed is dependant, how come light is not? 

[marcospolo]

 

Ralf;

 

 

[The person is moving at 10 mph relative to the air. The wave is moving at 750 mph relative to the air. The air gap is shrinking at 760 mph. There is nothing moving at 760 mph. A 2nd person could say, the speed of the wave relative to the 1st person is 760, but that changes the reference point, which is now moving. (the core idea of relativity!)]

 

 

[A 2nd observer would say the speed of the light relative to you is c+10. Equivalent to, the gap between you and the light is shrinking at the rate of c+10. Light speed is defined as relative to space/vacuum, not relative to an object. Your measurement of the oncoming light would be c, resulting from the effects of your motion.

[it's still a case of closing speed, since there are 2 objects moving simultaneously.

Your definition produces a phantom object moving at a phantom speed.]

 

 

This one comment "Light speed is defined as relative to space/vacuum, not relative to an object."  is the reason why Einstein's Special relativity is wrong!

 

Einstein first says that light is absolute to space, then one minute later, he swaps to having it relative to a stationary observer. Then because either observer can be that stationary one, it means that light must always go at c for anyone. Which is FALSE!

 

Where Einstein went wrong! Maxwell:  The speed of light in a vacuum is relative to the vacuum. The speed of light in a diamond is relative to the diamond. The speed of light in Water is relative to the water. Einstein:  The speed of light in a vacuum is relative to a person standing on a railway station!   Light must always transmit at the constant velocity of 300,000 km/s through a vacuum, regardless of the velocities of any material bodies which may also be traveling through that same vacuum at some other velocity. (any material bodies such as, Trains, people standing on railway stations, or space ships or Twins or the Earth)

So light will NOT be measured at “c” by everyone of those observers, relative to themselves. But it will be measured at “c” relative only to the medium its moving in. (we can use a “virtual” origin to measure lights speed, we don’t need to have an absolute, existing origin or “frame of reference”.

 

Thus, it appears that Einstein was fooled by his own algebraic descriptions and measurements. In fact, there never was a real “problem with the velocity of light” that needed any solution.! Special Relativity is a solution to a problem that does not exist.

[ralfcis]

"Prove or even explain how light speed is independant to the reciever's speed."

 

It all depends on how you define relative velocity which almost everyone doesn't understand. For the above statement to be true, v+c=c for the receiver. Sluggo tries to change the subject saying v+c= c for the source. People often confuse this statement with c is independent of the velocity of the source. The source's speed can't  push light or sound any faster through the medium but for sound, if the source or medium have a relative velocity to each other, that velocity will be added to the relative velocity of the sound to the source. While light can't be pushed by the source, the source's velocity will not add to the relative velocity between the source and the light. Apparently a physical entity can't have a relative velocity to nothing (a vacuum) or light which has a relative velocity to the vacuum but it can have a relative velocity to stuff suspended in that vacuum such as planets. Someone explain that one to me.

 

How Einy explains it in the train example is setting a sync'd start time such that x, the start distance and x', the distance the train end is from the source at the time the light hits the train end, results in c=x/t=x'/t'. That's just some artificially forced math to me. It's not even a valid sync of train and platform clocks as the two clocks re-unite with different values which would normally indicate a twin paradox type age difference has occurred which it hasn't.

[marcospolo]

"Prove or even explain how light speed is independant to the reciever's speed."

 

It all depends on how you define relative velocity which almost everyone doesn't understand. For the above statement to be true, v+c=c for the receiver. Sluggo tries to change the subject saying v+c= c for the source. People often confuse this statement with c is independent of the velocity of the source. The source's speed can't  push light or sound any faster through the medium but for sound, if the source or medium have a relative velocity to each other, that velocity will be added to the relative velocity of the sound to the source. While light can't be pushed by the source, the source's velocity will not add to the relative velocity between the source and the light. Apparently a physical entity can't have a relative velocity to nothing (a vacuum) or light which has a relative velocity to the vacuum but it can have a relative velocity to stuff suspended in that vacuum such as planets. Someone explain that one to me.

 

How Einy explains it in the train example is setting a sync'd start time such that x, the start distance and x', the distance the train end is from the source at the time the light hits the train end, results in c=x/t=x'/t'. That's just some artificially forced math to me. It's not even a valid sync of train and platform clocks as the two clocks re-unite with different values which would normally indicate a twin paradox type age difference has occurred which it hasn't.

But sound speed which is controlled solely by the medium it's in, that would be air, which we will assume is practically motionless compared to the speed of sound, then the speed of the source is not going to affect the sound speed in any way.  Also true is the fact that sound is not effected by the motion of the person hearing it.  Sound goes at "s" 760mph regardless of the motion of the source OR the motion of the receiver, OR the speed of anything else that happens to be in that air at the same time.  Sound always goes at "s" regardless of who is listening or who made the sound.

If a jet fighter fires a gun then the gunshot sound will still only ever be moving at 760mph regardless of the speed of the fighter.

Same exactly with light.

Light velocity is only ever "c" relative to the medium called "vacuum".  Light speed won't ever be measured at anything other than "c" relative to the vacuum, which we must assume is not moving anywhere.   But "observers" and "sources" of light sure are in motion.  So, exactly like with sound waves, when an observer who is doing velocity "v" towards a light source, he is going to have a closing speed of c+v.  But light is still only really moving at c.

Now if we insist as Einstein desires, to make that observer ignorant of his condition of motion, then he MUST claim that he just measured light to be going at c+v, as he has no other frame of reference from which to take accurate measurements.

However, the problem is that Einstein already has done a switcheroo, as how did we calculate the speed of the observer?  We claim that light's speed is always "c", but against what reference do we measure the speed of the observer?

Hint, it was the "absolute background frame of reference", which Einstein requires in all his theories, but claims that it doesn't exist.

It exists all right, but it's IMAGINARY, exactly like every frame of reference, which we create ad-hoc as and when we require them to do calculations.

[ralfcis]

So fn wrong but now I understand why. PS. The CR4 forum will welcome you with open arms.

 

1. Sound 760mph relative to the medium + your motion relative to the medium = your total relative velocity to sound which equals sound's relative velocity to you. Also add in windspeed relative to you because that's the motion of the medium.

 

2. Also NOT true is the fact that sound speed is not effected by the motion of the person hearing it.

 

3. Sound always goes at "s" relative to the medium but not regardless of who is listening or who made the sound if they have a relative velocity to the medium.

 

4. Not Same exactly with light.

 

5.which we must assume is not moving anywhere. No relative velocity to vacuum but that would mean we can't get a relative velocity to stuff stuck in the vacuum either which is not right.

 

6.I can't read anymore of this.

[marcospolo]

So fn wrong but now I understand why. PS. The CR4 forum will welcome you with open arms.

 

1. Sound 760mph relative to the medium + your motion relative to the medium = your total relative velocity to sound which equals sound's relative velocity to you. Also add in windspeed relative to you because that's the motion of the medium.

 

<Thats what I said.  The closing speed is s+v but s is still 760 relative to the medium.  The medium is not moving, why would you think it has a velocity? (unless you are going to claim that the sound wave does not move, its the air that moves while the sound stays still!>

 

2. Also NOT true is the fact that sound speed is not effected by the motion of the person hearing it.

 

<Sound SPEED is not affected by the motion of the dectector or the emitter.  What is noticed is the rate at which each individual wave front passes a detector, giving a faster frequency, higher pitch, but each wave front, the sound speed remains at 760mph relative only to the air medium.>

 

3. Sound always goes at "s" relative to the medium but not regardless of who is listening or who made the sound if they have a relative velocity to the medium.

 

<Sound cares not if someone is there listening, it will ony go at "s" wether you are there to hear it, moving or not. No moving dectector or emitter will affect sounds speed in still air. do you agree?>

 

4. Not Same exactly with light.

 

<Its is, why would you think differently? please explain.>

 

5.which we must assume is not moving anywhere. No relative velocity to vacuum but that would mean we can't get a relative velocity to stuff stuck in the vacuum either which is not right.

 

<Relative to the medium, for sound or for light.  If you want to think the medium is moving somewhere, fine, but sound or light cant move any differently regardless of the motion of the medium.

Take light emitted from a source embedded inside a diamond, (a large, long diamond..)  that light will go slower than light through air, acording to refractive index... and its is only possible to be relative to the diamond.  Never to any other detector moving or not.  A measurement will get diamond light speed + the speed of the diamond, relative to the measuring device.>

 

 

 

6.I can't read anymore of this.

 

<Its too sensible?>

[sluggo]

"If Bob drove 60 miles at 60 mph to see Alice, he would see her in 60 min. If he asked her to leave at the same time and drive to meet him, he would see her in 30 min. No one exceeded the speed limit, they only drove half the distance simultaneously.]"

 

But the relative velocity would be 120 mph. Alice's car is going 60 mph towards Bob. Bob's car is going 60 mph towards Alice. No one is exceeding the speed limit but their relative velocity is 120 mph. The gap between them is also closing at 120 mph which a person on the side of the road witnesses. The closing speed equals the relative velocity except for an insignificant relativistic effect. But with higher relativistic effect, the closing speed gets up to two times the relative velocity. Bob and Alice could  see their relative velocity is also 120mph with radar guns. I just don't see how two cars headed towards each other wouldn't crash at twice the speed as one would being parked and the other hitting him at 60mph. That's how head on collisions work. If what you're saying is true then we live in 2 different physical universes.

 

 

Agree with gap closing at 120. Alice moves 30 mi in 30 min, v=60. Bob moves 30 mi in 30 min, v=60.

Note, they move simultaneously 

We have accounted for all objects in motion. Where is the thing moving at 120?

[sluggo]

Also true is the fact that sound is not effected by the motion of the person hearing it. 

 

Doppler shift results from relative motion of source and detector.

Most people have heard the variation from sirens.