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Feb2313 08:40 AM
ZapperZ

1 
41,634 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,284 
A general summary of the experiment is that when the light clock is stationary on the platform it runs as normal, up...

T 09:25 AM
jtbell

15 
697 
Do experiments like 1971's Hafele & Keating show that SR relativistic effects of time dilation are not mere products...

T 01:01 AM
PeterDonis

5 
396 
As you may already know, given a timelike congruence describing some extended body with worldtube ##\mu## embedded...

Y 10:05 PM
PeterDonis

31 
3,203 
Constant for all observers?
I have heard that maxwell showed that the speed of light is constant for all observers...

Y 07:54 PM
DaleSpam

46 
2,353 
I understood that the basic idea of the MichelsonMorley experiment was to measure the velocity of light, as seen from...

Y 09:01 AM
ghwellsjr

2 
173 
The basic question was inspired by some other recent threads on the "fabric of space". If we imagine a 2d spatial...

Y 05:44 AM
haael

4 
209 
I've always been interested in SpaceTime fabric and have been trying to get a clear answer to whether or not its an...

Y 02:12 AM
Bandersnatch

14 
605 
I've read that the Alcubierre Drive depends on the existence of negative mass, but I've seen that physicists say it...

Y 02:06 AM
Simon Bridge

1 
111 
Isn't the force of gravity just a result of the shape of space as it is affected by masses within it? Why is it...

Jul2814 08:05 PM
pervect

3 
271 
Hi all. I'm working on a project that requires me to perform calculations in Fermi normal coordinates to certain...

Jul2814 05:47 PM
George Jones

3 
341 
Hi, I am trying to show explicitly the isotropy of the stress energy tensor for a scalar field Phi.
By varying the...

Jul2814 11:27 AM
George Jones

7 
458 
I want to write a sciencefiction story concerning the rapid increase in technology affecting the speed at which...

Jul2814 09:13 AM
ghwellsjr

3 
358 
According to Einstein (e.g. in his book The Meaning of Relativity), a clock rotating about a central clock will be...

Jul2814 12:51 AM
HALON

21 
2,206 
Whatever spacetime be made of strings or some other erotic substance it seems that it doesn't have mass so what causes...

Jul2714 07:39 PM
DaleSpam

13 
407 
Thinking about how so much matter can be squeezed into a singularity, the answer (if I understand correctly) is that...

Jul2714 03:40 PM
Vanadium 50

6 
697 
Hi,
I would be really grateful if someone could help me with two questions I have, both have puzzled me on and off...

Jul2714 10:33 AM
CraigDxHypo

16 
806 
Here is a new video, addressing a common question on this forum:
jlTVIMOix3I
It's similar to that one, but has...

Jul2714 04:45 AM
A.T.

0 
248 
I have question on my own understanding.. So please correct me..
1. It is said that mass of photon is zero; Or it...

Jul2614 07:25 PM
Nugatory

3 
338 
I have a metric given as a line element differential ds^2. I have written down the 3x3 matrix with the coefficients. ...

Jul2614 06:56 PM
ChrisVer

8 
379 
What does it mean to boost something along the z axis?
To give some acceleration to it, or to spatially translate it?...

Jul2514 09:52 PM
WannabeNewton

4 
421 
So I was thinking about the space time field and trying to wrap my head around how it is actually bent around a mass. ...

Jul2514 12:38 PM
Nugatory

1 
388 
If velocity is relative and if we cannot say which is moving away from what *objectivley, how do we say that time...

Jul2514 01:23 AM
objecta99

61 
3,395 
It is my understanding that at the most fundamental level, a black hole is simply an object with a gravitational field...

Jul2414 03:31 PM
willoughby

17 
731 
I was reading Einstein's paper "The Foundation of the General Theory of Relativity" and as i understood, he tried to...

Jul2414 08:03 AM
nixed

3 
854 
We measure time based off of atomic vibrations, so time dilation from gravity and velocity are nothing more than...

Jul2414 06:31 AM
DaleSpam

12 
817 
Hello everyone! My question is this: Do we believe time is a constant and forces such as gravity affect our perception...

Jul2314 12:18 PM
DaleSpam

41 
3,512 
Is there a simple intuitive description of what the Ricci tensor and scalar represent?
I have what seems to me a...

Jul2314 11:24 AM
robphy

5 
739 
1. What exactly is the cosmological constant, what is its value (or how do you derive it if it is something that must...

Jul2214 09:43 PM
bcrowell

2 
603 
I was wondering why can't I use formulas from the "Special Relativity" in cases like:
F=mv^2/r Or F=qv•B...

Jul2214 12:56 AM
ghost313

2 
581 
Are there any EXACT solutions similar to Schwarzschild or Kerr in a spacetime which is not asymptotically flat; e.g....

Jul2114 01:36 PM
George Jones

3 
1,128 
Hello everyone. I am attempting to teach myself about special relativity, and have learned a derivation for the...

Jul2114 01:31 PM
toothpaste666

8 
935 
I got stuck in deriving the velocity of the particle from the acceleration equation. Here are the details of the...

Jul2014 10:07 PM
ecastro

6 
1,188 
Hello. I'm a layperson curious about physics.
I've read that Quantum Gravity could eliminate the predicted...

Jul2014 06:22 PM
sshai45

11 
1,523 
I have recently gone over the derivation of the stress energy momentum tensor elements for the special case of dust....

Jul2014 04:42 PM
spacetime

4 
913 
*Edit: I noticed I may have posted this question on the wrong forum... if this is the case, could you please move it...

Jul1914 10:23 AM
coleman123

8 
1,983 
its been years since I took a physics course so I might have what amounts to a really dumb question. However, I got...

Jul1914 10:21 AM
objecta99

19 
1,845 
Hi
I am a new(ish) student of general relativity. I am currently reading 'Relativitiy DeMystified'
However...

Jul1914 03:58 AM
Nugatory

1 
870 
Hi, I'm trying to derive the displacement of an object with proper acceleration (constant) α.
t is our laboratory...

Jul1814 06:45 PM
pervect

2 
1,072 
Hi
I am teaching myself GTR from Dirac's book...

Jul1814 04:00 PM
WannabeNewton

3 
1,032 
Starting at the beginning and have been having some difficulty explaining the implications of the constancy of the...

Jul1814 03:30 PM
etcota

3 
997 