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Feb2313 08:40 AM
ZapperZ

1 
37,344 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,108 
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 
425 
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 
431 
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 
394 
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 
509 
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 
287 
Could spacetime itself be a field?

Feb2414 12:01 AM
Fredrik

5 
279 
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 
615 
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 
474 
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 
603 
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 
436 
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 
615 
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 
257 
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 
505 
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 
293 
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 
312 
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 
352 
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 
468 
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 
969 
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 
564 
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 
881 
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 
495 
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 
2,203 
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 
596 
On page 161 of Carroll's Spacetime and Geometry, Carroll writes that
\delta...

Feb1814 03:32 PM
Bill_K

9 
345 
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 
258 
I am currently taking an undergraduate modern physics course that offers a brief overview of relativity. Let us...

Feb1814 07:49 AM
Chestermiller

12 
518 
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 
309 
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 
437 
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 
457 
Hello,
It is my understanding that in the case of two observers (A and B) passing each other at high speeds that due...

Feb1714 03:11 AM
Nugatory

1 
273 
I'm trying to understand the special theory of relativity. All answers I've found to the problem below seem to provide...

Feb1714 02:45 AM
BruceW

21 
693 
Would someone be kind enough to tell me if I'm getting this correct.
http://s30.postimg.org/hql7gx8ox/Prob_4.gif
...

Feb1614 02:41 PM
PeterDonis

5 
340 
I'm trying to find examples of stressenergy tensors from exact solutions of the EFE corresponding physically to...

Feb1614 06:30 AM
TrickyDicky

36 
1,053 
Why do we always need to define simultaneity in relativity. The moving train with a light signal at the mid point...

Feb1614 04:15 AM
bahamagreen

6 
461 
The "s" in the geodesic equation refers to the "surface area" for that portion of the orbit around a star or black...

Feb1514 07:53 PM
DaleSpam

3 
320 
In classical mechanics you want to calculate the moment of inertia for hollow & solid:
lines, triangles,...

Feb1414 06:04 PM
WannabeNewton

5 
416 
Hello fellow PF goers
I am having trouble with coordinates in curved space time lately, allow me to demonstrate my...

Feb1414 12:55 PM
DaleSpam

5 
360 
I am starting to learn Special and General realitivity by reading through Bernard F. Schutz's book "A First Course in...

Feb1314 05:40 PM
pervect

9 
447 
After a recent conversation, I was trying to determine if there is an online authoritative definition for the age of...

Feb1314 05:06 PM
TrickyDicky

13 
468 
It is said that the light we see from a star a million light years away is actually what happened a million years ago,...

Feb1314 10:55 AM
phinds

6 
1,074 