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Feb2313 08:40 AM
ZapperZ

1 
40,585 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
40,240 
Bit confused regarding how noninertial frames can be treated in GR (and by noninertial i mean affected by some kind...

Feb2814 01:58 AM
WannabeNewton

1 
287 
I am trying to write the Einstein field equations
$$R_{\mu\nu}\frac{1}{2}g_{\mu\nu} R=\frac{8\pi G}{c^4}T_{\mu\nu}$$...

Feb2714 10:56 PM
Nabigh R

2 
462 
There is a moving light clock at a certain velocity. For an outside observer, the light just seemed to be traveling in...

Feb2714 07:04 PM
DaleSpam

28 
1,052 
If we consider a perfect relativistic fluid it has energy momentum tensor
$$T^{\mu \nu} = (\rho + p) U^\mu U^\nu +...

Feb2714 05:53 PM
TrickyDicky

15 
471 
The solution of Einstein's field equations for a simple black hole show a slowing of time as you get close to the...

Feb2714 11:44 AM
PAllen

37 
2,033 
Hi guys,
Firstly apologies if this question has been asked before (or are stupid questions) or better explained...

Feb2714 08:58 AM
jtbell

5 
558 
This is a purely terminological question. Consider the following setup: we have two inertial observers A and B at rest...

Feb2614 04:28 PM
bcrowell

14 
956 
Hello
To demonstrate that we can deduce from special relativity the existence of an observer who finds that his...

Feb2614 01:26 PM
DaleSpam

54 
2,119 
I recently watched a video in Einstein's train though experiment.
www.youtube.com/watch?v=wteiuxyqtoM
From what...

Feb2614 11:29 AM
Yashbhatt

17 
719 
Suppose we have an event horizon H which is a lightlike, closed 2surface. Photons radiated outwards at the horizon...

Feb2514 09:41 PM
George Jones

3 
339 
Trying to understand the conservation of relativistic momentum, I thought of this problem.
It's very simple, and...

Feb2514 03:55 PM
epovo

2 
286 
I was just reading the sci.physics.faq http://math.ucr.edu/home/baez/physics/Relativity/SR/rigid_disk.html on the...

Feb2514 02:46 PM
bcrowell

15 
491 
Hi all, I tried searching for this but failed to find an answer to my question. I am having an issue with properly...

Feb2514 01:01 PM
scinoob

12 
793 
Howdy,
This is my first post. Please be gentle. ;)
I have been thinking about the speed of light.
Scenario...

Feb2514 09:19 AM
dauto

4 
447 
Sorry I'm new to this.
There are apparently four forces in the universe: Gravity, EM, Weak and Strong.
Is gravity...

Feb2414 04:19 PM
pervect

7 
628 
hi guys i have question can any body answer please.
why the light fell in to the black hole whether it have no mass.

Feb2414 02:43 AM
mra20x

3 
332 
Could spacetime itself be a field?

Feb2414 12:01 AM
Fredrik

5 
322 
i have asked my physics and maths teacher a question which they could not answer, the question follows:
Does the...

Feb2314 06:30 PM
pervect

15 
775 
I'm working through A. Zee's new EGR book, and I came to a step on tidal forces I couldn't follow. He presents the...

Feb2314 10:33 AM
russelljbarry15

4 
522 
Is there an absolute sequence of events in the universe independent of observation? It seems like so much emphasis is...

Feb2314 03:08 AM
adrian_m

6 
674 
In the spirit of this forum I should first announce:
generally, I have no idea what I'm talking about but look for...

Feb2314 12:29 AM
ghwellsjr

6 
488 
In Special Relativity the example is given of a pole that alternates color, as seen in its own rest frame. Someone in...

Feb2214 09:56 PM
gabeeisenstei

19 
696 
Before I get down to business, I would like to note (you don't have to read this; feel free to skip to where it says...

Feb2214 06:31 PM
pervect

2 
313 
Is it true that the speed of light is a conversion factor between time and space?
and that D = C*T?
and if it...

Feb2214 05:51 PM
FactChecker

8 
562 
When we way that
\frac{d^3p}{p_0}=\frac{d^3p}{\sqrt{m^2+\vec{p}^2}}
is the invariant volume element, is that...

Feb2114 10:36 PM
pellman

2 
364 
I am currently studying special relativity on my own and I am looking into space time and space time diagrams. While...

Feb2114 07:31 PM
PeterDonis

5 
398 
In another thread we determined that the proper total force acting on an orbiting object in the Schwarzschild metric,...

Feb2114 09:11 AM
Mentz114

5 
416 
Dumb question....but thought I'd throw it out there.
So, ever since I was a little kid of 6 or so, I loved to look...

Feb2114 08:55 AM
phinds

13 
545 
This is a very basic question, but I cannot get my head around the following: Any physical system should be invariant...

Feb2014 02:22 PM
PAllen

34 
1,209 
Let's imagine a rocket orbiting the earth. The rocket could be any real rocket with moderate speed, so that...

Feb1914 07:51 PM
PAllen

11 
628 
I was reading some posts on one of my previous threads (great discussion there btw) and I red something that I really...

Feb1914 06:20 PM
WannabeNewton

23 
1,013 
I've been watching the Stanford lectures on GR by Leonard Susskind and according to him the metric tensor is not...

Feb1914 02:08 PM
Chestermiller

9 
718 
I have been wondering what to expect if there was a hole,
from pole to pole, that inside which we could measure the...

Feb1914 12:16 PM
PeterDonis

88 
2,649 
When I studied special relativity for the first time, I encountered the exemple
of a infinite neutral wire in the...

Feb1814 09:18 PM
jartsa

8 
720 
On page 161 of Carroll's Spacetime and Geometry, Carroll writes that
\delta...

Feb1814 03:32 PM
Bill_K

9 
417 
We all know that the energymomentum tensor for dust is just ##T^{\alpha\beta}=\rho_0 v^\alpha v^\beta##, where...

Feb1814 02:57 PM
dEdt

0 
292 
I am currently taking an undergraduate modern physics course that offers a brief overview of relativity. Let us...

Feb1814 07:49 AM
Chestermiller

12 
568 
It is said that Relativity proves that if one travels near the speed of light that time slows down, i.e. that the twin...

Feb1814 05:38 AM
DaleSpam

2 
348 
Let's say there's a wormhole entrance on the floor of my room, and the exit would be on the ceiling. If I drop a ball...

Feb1714 11:17 PM
HarryRool

9 
520 
If light approaches a black hole will it accelerate? I think this question ties in with whether light has mass or not....

Feb1714 10:30 PM
A.T.

10 
529 