Twin paradox "resolution" article

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[TVF]: But for those who want to understand SR (at least for historical reasons), your descriptions miss the mark by not accepting the two postulates of SR, especially the one that the speed of light is c for all observers. -|Tom|-
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Understanding SR is a real battle for me. To elaborate, consider two twins in an airport terminal both traveling on separate conveyer belts in the same direction; one conveyer belt travels faster and both twins have flashlights. Now, suppose both twin turn on their light.
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[TVF]: In SR, every object may regard itself as at rest. No matter how fast one travels, light will still have a relative speed of c.
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Now, the most confusing part is that as soon as light "leaves" the two torches I just cannot see why the speed of light is the same for both twins. I'm locked into thinking that a "decoupling" of regions occurs, i.e., as light "leaves" the flashlights, that light need not be associated with the twins that emitted the light intuitively speaking. The emitted light has a life on its own and travels through space independently in my view. Is this the case? Does it need to be associated with the frame attached to the object that emitted the light? This sounds fantastical to me. Does one assign a "boxed" portion of space around the frame containing the twin? Does one assume that this "boxed" portion is traveling with the light emitting object? So that in this way the light travels with a relative velocity of <i>c</i> for each twin? Can someone please clarify how light that, once emitted, is linked with a particular frame. I think that I do not understand this at all.

The above post is not complete, so let me eleborate my reasoning further. In case of the twins above, I somehow think that light travels independently once emitted, so that the constant speed of light for all observers sounds unintuitive. This dilemma can be explained in a simpler fashion. A bouncing ray of light between mirrors is often used to derive the gamma factor by using a simple pythagoras argument. Now, my question is as follows. Does the pulse of light really travel with the same velocity between the mirrors, that is, does the ray of light really hit the mirror in the centre point of the opposite mirror? To put it more extremely, if we have a laser gun traveling near the speed of light, does the laser really hit the target in the centre line of the gun if the gun is pointing towards a target perpendicular to the direction of motion?

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[Jan]: consider two twins in an airport terminal both traveling on separate conveyer belts in the same direction; one conveyer belt travels faster and both twins have flashlights. Now, suppose both twin turn on their light. Now, the most confusing part is that as soon as light "leaves" the two torches I just cannot see why the speed of light is the same for both twins.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Try thinking backwards here. The constancy of the speed of light for all observers is not an experimental result; it is a postulate of SR. So do as the theory says and assume that is true. That forces each observer to adjust local clocks in time and rate of ticking so that the measured speed of light will be c, regardless of what that speed "really" is.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>The emitted light has a life on its own and travels through space independently in my view. Is this the case? Does it need to be associated with the frame attached to the object that emitted the light? This sounds fantastical to me. Does one assign a "boxed" portion of space around the frame containing the twin? Does one assume that this "boxed" portion is traveling with the light emitting object?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

In SR, all light travels at speed c relative to all frames because motion changes time rates and time synchronization so as to keep c constant. There is no association of any light beam with any particular frame.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Does the pulse of light really travel with the same velocity between the mirrors, that is, does the ray of light really hit the mirror in the centre point of the opposite mirror? To put it more extremely, if we have a laser gun traveling near the speed of light, does the laser really hit the target in the centre line of the gun if the gun is pointing towards a target perpendicular to the direction of motion?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

If the beam is aimed perpendicular to a mirror, it will bounce perpendicular, regardless of how others perceive the state of motion of the mirrors. So one frame's perpendicular bounces will be another frame's sawtooth bounces as the mirrors fly through space.

In SR, ir's all relative. -|Tom|-

Jan,

Glad to see you find the invariance of light counter intuitive. Like Tom says you can merely accept it as fact and become a Relavists or you can think of alternative solutions.

What I say next is my own view and is not scientifically tested or proven.

It is my opinion that the invariance of light is actually merely an illusion.

It may be the result of the production of light being a quantum energy function along an energy or information carrier beam which if I am right is the same carrier that accounts for Particle Entanglement.

What this means then is that the production of light being quantum energy related causes the time and place of the existance of a photon to change as his relative velocity to the source changes.

Put in the simplest form it means light appears to remain constant regardless of velocity relative to or from the source but that you are not seeing the same photon or the same photon is being delayed or enhanced in its production as a function of c+v or c-v.

That simplifies understanding but eliminates the emputus for Relativity.

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[Mac]: Glad to see you find the invariance of light counter intuitive. Like Tom says you can merely accept it as fact and become a Relavists or you can think of alternative solutions.
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Should I be glad? I'm covered in sorrow by abandoning my "gut feeling". Like you said, perhaps I just need to accept it, but it adds a bitter taste. The invariance of light is probably hard to swallow because we are actually a third observer when looking at two twins traveling and one twin is overtaking the other. As the third observer, I see the light "sharing" the same space containing both twins. Hence it seems utterly illogical to suddenly assume that the SOL is the same for both twins, and in order to reconcile this, the physical attributes of the twins need to change so that both twins measure "c". We are left with a world that is not what it appears to be.

Just another "gedanken experiment" to question the invariance of light. Suppose one has a cylinder spinning around its own centre line and there is a laser emitting light from the centre line onto the inner side of the cylinder. The cylinder is in a deep vacuum. Just think this cylinder as the drum of a washing machine where the laser is *fixed* on the driving shaft. According to SR, one is allowed to take the centre line to be stationary. Before we start spinning the cylinder with laser, we are "hard" marking the laser spot on the cylinder. Now imagine spinning the drum such that the tangential speed of the outer rim approaches a significant fraction of the SOL with respect to its centre. Q: Does the laser spot stay on the marked spot?

Forget what I said about the spinning cylinder in the post above; it is flawed. What I want ask is the following: Does a laser pulse from a horizontal moving laser, with respect to some "fixed" frame, get a horizontal velocity component with respect to that frame?