New answers tagged observers
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Does special relativity also imply that speed of sound is constant for all observers irrespective of their relative motion?
The speed of sound (speed of pressure waves) is fundamentally related to the fluid medium in which the pressure waves travel. The governing reference frame for sound wave analysis is the frame at rest ...
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Accepted
Does special relativity also imply that speed of sound is constant for all observers irrespective of their relative motion?
The speed of sound is not constant for all observers, but this does not contradict the fact that the laws of physics are the same in all reference frames or imply that you can detect your absolute ...
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Does special relativity also imply that speed of sound is constant for all observers irrespective of their relative motion?
The statement is that the laws of physics are the same in both frames, not that a specific solution will be the same in all frames. The laws of physics are based on differential equations. To get an ...
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Does special relativity also imply that speed of sound is constant for all observers irrespective of their relative motion?
No.
The speed of light is more closely related to the structure of spacetime than anything else. Traveling along null curves, a photon moves at the highest speed it can while staying on “causal” paths,...
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How can coordinates be meaningless in General Relativity?
The quote that prompted this question is my fault, so perhaps I should answer this.
In context I wrote
[C]oordinates are meaningless. You can calculate any physically meaningful quantity using any ...
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How can coordinates be meaningless in General Relativity?
Coordinates are not meaningless. But perhaps a better word would be unimportant - in the sense that the physics does not care what coordinate system you use and all measurements that you could make ...
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How can coordinates be meaningless in General Relativity?
Aidan Beecher asked: "Why isn't it possible to find any choice of coordinates that correspond to a particular observer, like in special relativity, where it is possible to Lorentz transform into ...
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Accepted
Is gravitational length contraction only in one direction?
When it lands on the surface, gravity will compress it.
This is not what gravitational length contraction is about. If we have a cube on the ground it will be slightly shorter due to the compression ...
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What will going near the speed of light would look like?
In the first case (where B believes A to be in motion), if time
dilation is supposed to make person A move slowly (from B's frame of
reference), will B just see an almost stationary picture of person ...
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What will going near the speed of light would look like?
Let's get rid of the issue of moving towards or moving away by saying that A is traveling in a circle around B and B is rotating to keep a constant eye on A. And then we'll say that A is a long ...
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What will going near the speed of light would look like?
If you really mean 'see', as in experience in real time with their eyes, then they won't see anything. If I pass you at the speed of light, I will be at an easily visible distance for too short a ...
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What will going near the speed of light would look like?
The situation becomes clear if we note how the clocks would be compared. One way is to have one clock per wagon in the train, all of them synchronized in the train's frame.
The bystander would always ...
- 16.8k
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What will going near the speed of light would look like?
If A is moving toward B, he will see B's clock ticking in "fast forward", but will realize this is partly because B keeps getting closer, so light from each tick of B's clock arrives faster ...
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What will going near the speed of light would look like?
The situation is symmetric. A sees B's clock tick slower, and B sees A's clock tick slower. At very nearly the speed of light that time dilation will make each person appear to be not flowing through ...
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Is gravitational length contraction only in one direction?
This effect primarily happens in the direction of the gravitational pull (like down the hill in our example). It doesn’t happen sideways (perpendicular to the pull), just like the rubber band would ...
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Why does an accelerated clock record fewer events?
This had me confused:
The clock also continuously records its readings so that at the end of the experiment there is a single record upon which all observers will agree
IMO, That's an unnecessary ...
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Explaining the phrase "as viewed by A, clock $\mathfrak B$ appears to be ticking faster than clock $\mathfrak C$"
"When viewed from the surface of the Earth, the clocks on the satellites appear to be ticking faster than identical clocks on the ground.".
This ubiquitous terminology used in the context of ...
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Why does an accelerated clock record fewer events?
The physical properties like frequencies of atoms are of course valid in the proper time of the object.
One well known effect is the detection of muons. They are formed about twelve thousand meters in ...
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Why does an accelerated clock record fewer events?
Your first mistake is here: "The clock is accelerated and its tick rate is observed to decrease by all observers relative to the tick rates of their local clocks."
After a clock changes ...
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Why does an accelerated clock record fewer events?
No, you misunderstand what is happening. The difference in time is a consequence of the geometry of spacetime.
It might help to consider an analogy with 3d space. Suppose you drive your car in a ...
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Why is $dt/d\tau=\gamma$? What is $dt/d\tau$ supposed to mean exactly?
There exists a clear contradiction between the relation for Lorentz factor of special relativity and in Lorentz transformation matrix. In special relativity, Lorentz factor is the ratio between ...
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