All Questions
23
questions
1
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0
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42
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Radiation from a stationary charge relative to earth for a free falling observer
It is my understanding that if we have a charge at rest on earth, a free falling observer will see it radiating, as the charge is in an accelerated frame of reference. This observer can in principle ...
- 795
1
vote
0
answers
72
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Coordinate transformation and absolute motion in general relativity
In special relativity, all motion is relative. But in the presence of black hole, all motion is with respect to black hole. The curvature of spacetime depends on how far we are away from the black ...
- 134
2
votes
1
answer
546
views
How do they set the clocks on spacecraft visiting several other planets?
Scientists have sent spacecraft into distant space passing nearby other planets on the voyage. How do they set the clocks to adjust for kinetic time dilation (special relativity) and gravitational ...
- 4,783
1
vote
0
answers
106
views
Energy is the time component of 4-momentum in SR: Proof as per R. Wald's book
This is an excerpt fom R. Wald's book on General Relativity (page 61). I'm not able to understand how he deduces that $E$ must be the time component of $p^a$ with only the assertions made before this ...
- 107
-10
votes
1
answer
555
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Big Ben Paradox? [closed]
Consider a distant observer traveling at 0.867 c ( $\gamma=2$ ) relative to the solar system along the line that is collinear with the sun's axis of rotation. As the clockwork solar system spins ...
- 79
0
votes
0
answers
27
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Is it correct to say that acceleration slows the frequency of an oscillator?
My question is based on differential aging or differential timekeeping due to, 1) increased speed, and 2) proximity to center of gravitational field. As far as I know, both involve acceleration, and ...
- 1
1
vote
2
answers
327
views
If the Lorentz symmetry was broken, would literally all fundamental laws change for different observers?
Perhaps this is a stupid question, but as a student I have some questions about Lorentz symmetry and the fundamental laws of physics.
According to what I've been reading, the Lorentz symmetry (or the ...
- 2,462
-4
votes
2
answers
159
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Is the Earth's Orbit Slower When Big Ben is Time Dilated?
Either way, the answer to this question has the most profound consequences imaginable. Therefore the question will be asked in a more concrete manner:
Consider a distant observer traveling at .867c ...
- 79
1
vote
0
answers
170
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Rindler Observers
In the process of transition from STR to GR, I'm trying to understand what Rindler observers actually are. Here is how one of the questions from our assignment defines them:
If the distance between B ...
- 67
-3
votes
3
answers
454
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Does time really slow near the speed of light or does it only seem that way to an outside observer? [duplicate]
I was lying awake last night struggling to sleep as one does, thinking about time and Einstein's concepts of relativity and having some fun with thought experiments similar to the one Einstein ...
0
votes
1
answer
110
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Why the proper time of photon is zero? [duplicate]
I'm currently taking classes on General Relativity, and whilst working on Geodesis equation:
Find out that for mass particle q is equivalent to proper time but in case of photon the proper time of ...
- 33
-2
votes
4
answers
183
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Doesn't Curved Spacetime Falsify the First Postulate?
It would appear that curved spacetime and the first postulate of special relativity are mutually exclusive.
Consider a distant observer traveling at .866 c relative to the solar system along the line ...
- 79
1
vote
1
answer
610
views
How does the derivative of time with respect to proper time equals gamma?
So, I want to really get a deep understanding of everything that goes beneath special relativity. Since I teach myself with books, I have no teacher to ask to which makes things a bit harder most of ...
5
votes
3
answers
1k
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Does Kepler's 3rd law of planetary motion violate the first postulate of special relativity?
Consider a distant observer traveling at .866 c relative to the solar system along the line that is co-linear with the sun's axis of rotation. According to his/her wristwatch the observer measures the ...
- 79
0
votes
0
answers
144
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Mach's conjecture and the twin paradox in an empty universe
What would happen if we revisit the twin paradox in an empty universe? Indeed, according to Mach's principle, when a spaceship accelerates in our universe filled with too many stars and other objects, ...
- 2,503