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Feb2313 08:40 AM
ZapperZ

1 
42,472 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,123 
Hi
Just wondering about the orbital path of a high speed particle  eg electron in orbit. Is it length contracted?...

Aug214 11:24 PM
jartsa

3 
350 
Hi
I have a new formula (or at least I think it's new) for predicting the wavelengths/frequencies of hydrogen's...

Aug214 03:35 PM
DaleSpam

1 
355 
I was thinking a bit earlier:
What if you created a particle at infinity (ignore the normal particle rules for...

Aug114 10:43 PM
pervect

2 
268 
I recognize the analytical usefulness of having time, a parameter. However, does time really exist? If so, is there a...

Aug114 11:37 AM
ChrisVer

21 
649 
Considering that speed of light is constant and finite, then why are the time dilatation and length contraction...

Aug114 10:16 AM
tonyxon22

6 
363 
We know that distant galaxies (which are expanding) are sometimes expanding at rates that do not conform with our...

Aug114 08:22 AM
Drakkith

2 
260 
From my understanding and from what I have read Quantum Mechanics and Relativity do not mix well. I understand that...

Jul3114 10:37 PM
WannabeNewton

3 
319 
This may be a stupid question, but have the various gravitational wave observatories around the world been tested by...

Jul3114 03:42 PM
PeterDonis

2 
224 
A general summary of the experiment is that when the light clock is stationary on the platform it runs as normal, up...

Jul3114 01:04 PM
tonyxon22

24 
1,264 
I’ve been thinking about Einstein’s gedankenexperiment (because I’m meta like that) regarding the sealed room on...

Jul3114 11:52 AM
Nugatory

13 
334 
Constant for all observers?
I have heard that maxwell showed that the speed of light is constant for all observers...

Jul2914 07:54 PM
DaleSpam

46 
2,973 
The basic question was inspired by some other recent threads on the "fabric of space". If we imagine a 2d spatial...

Jul2914 05:44 AM
haael

4 
379 
I've always been interested in SpaceTime fabric and have been trying to get a clear answer to whether or not its an...

Jul2914 02:12 AM
Bandersnatch

14 
812 
I've read that the Alcubierre Drive depends on the existence of negative mass, but I've seen that physicists say it...

Jul2914 02:06 AM
Simon Bridge

1 
268 
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 
452 
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 
474 
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 
606 
I want to write a sciencefiction story concerning the rapid increase in technology affecting the speed at which...

Jul2814 09:13 AM
ghwellsjr

3 
518 
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 
2,719 
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 
569 
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 
853 
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 
1,026 
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 
500 
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 
531 
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 
488 
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 
4,161 
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 
899 
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 
1,006 
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 
1,002 
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 
4,109 
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 
899 
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 
736 
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 
691 
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 
1,332 
Hello everyone. I am attempting to teach myself about special relativity, and have learned a derivation for the...

Jul2114 01:31 PM
toothpaste666

8 
1,114 
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 
1,374 
Hello. I'm a layperson curious about physics.
I've read that Quantum Gravity could eliminate the predicted...

Jul2014 06:22 PM
sshai45

11 
1,809 
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 
1,089 
*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 
2,203 
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 
2,153 