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Feb2313 08:40 AM
ZapperZ

1 
42,298 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,928 
Hey,
For a problem I am working on I need to know if the energymomentum tensor of the Reissner Nordstrom metric...

Feb1211 09:29 AM
Mentz114

1 
1,014 
Did this experiment show that there was no ether . Because one way the light had to move up stream and it would take...

Feb1111 08:05 PM
phyti

229 
22,537 
Hi all,
I've read some references to an example of a person on a train using a flashligt and one outside the train...

Feb1111 07:19 PM
Fredrik

2 
1,271 
Why does General Relativity breakdown at Plank Temperature?

Feb1111 12:49 PM
bcrowell

1 
1,081 
Hello! Is someone aware if there are lecture notes about Lie Groups from a physics course?
I would to study an...

Feb1111 06:57 AM
A. Neumaier

1 
841 
Hi,
It's found it Carroll that r=\frac{L^2}{GM(1+e\cos{((1\alpha)\phi)}} . He states that this means we've found...

Feb1111 03:17 AM
LAHLH

2 
1,601 
Maybe this question has already been asked, anyway, here it goes. The universe is expanding and according to...

Feb1011 11:50 AM
nicksauce

1 
1,307 
Howdy! I'm new to Physics Forum and glad to be part of the community.
I just finished reading Einstein's Special...

Feb1011 11:03 AM
Fredrik

14 
7,307 
Hello
This is a part of a simple paper about special relativity
http://img15.imageshack.us/img15/8789/91001769.jpg...

Feb911 09:41 PM
Dark_knight90

3 
864 
Lets say I'm in a train going the 1/2 the speed of light. I have a light source that releases signal photons.
I...

Feb911 04:59 PM
Joseph14

3 
953 
i am searching for a detailed discussion on the relativistic poisson brackets. where i can found it?

Feb911 09:23 AM
A. Neumaier

5 
1,362 
This is not a homework problem. It is personal project of mine. Pleases help
Say you have a space craft that for...

Feb811 11:21 PM
JesseM

3 
826 
So I did a degree some time ago and after watching a programme on TV, I decided to revisit relativity and set myself...

Feb811 07:05 PM
DaleSpam

149 
13,807 
Einstein synchronization, as it is conventionally defined, depends on subtle issues like the oneway speed of light. ...

Feb811 05:06 PM
gravuniverse

12 
1,842 
Can a freely floating observer do an experiment that tells him when he is crossing the event horizon?

Feb811 10:34 AM
DaleSpam

1 
547 
Let A and B be two points that are at rest relative to an inertial frame S. Let's say the distance between them is...

Feb811 10:32 AM
DaleSpam

1 
621 
I posted an LHC question a while back but did not get a reply. I'll ask a somewhat different, simplified and more...

Feb711 07:37 PM
teve

2 
1,679 
Hello,
I understand light can be accelerated in a gravitational field, because it follows the curves in the...

Feb711 07:20 PM
fzero

1 
2,047 
I was in math class today as we were learning about sine waves and frequency, and i kinda related it to light. Then I...

Feb711 05:02 PM
The_Original5

4 
998 
The argument I've heard following from Special Relativity is as follows:
Assume a causal influence can travel...

Feb711 10:59 AM
ZikZak

12 
2,012 
Good Afternoon,
After watching a TV program "Into the Universe" "Time Travel " I have some doubts left.
I know...

Feb611 11:26 PM
NoDoubt

7 
2,186 
Thus wrote PAM Dirac in his little monograph, "General Theory of Relativity", p.34t. More fully, "Even a light signal...

Feb611 06:48 PM
goedelite

4 
1,005 
Is it fair to say light speed will never be reached because the energy required has been dissipated or used during the...

Feb611 01:26 PM
fzero

9 
1,343 
Hi,
I've heard it said that for Schwarzschild spacetimes, then the coordinate 'r' is an affine parameter for radial...

Feb611 04:07 AM
LAHLH

8 
1,704 
will a 2m(rest length) car moving near lightspeed fall in a 1m hole?

Feb511 07:33 AM
harrylin

11 
2,013 
I just wanted to know what exactly is a wormhole.....

Feb411 06:33 PM
DaleSpam

1 
1,068 
Hello!
Here and there I find that it is possible to make the Christoffel symbols vanish on a curve (e.g. lecture...

Feb411 04:08 PM
bcrowell

8 
2,452 
hey,
does anyone of you know the reissnernordström metric, if there is a magnetic field instead of the coulomb...

Feb411 02:10 PM
Gavroy

4 
2,031 
Hi!
I'm trying to definitely solve the twin paradox (after 5 years of efforts :) )
In every physics textbook, it...

Feb411 01:02 PM
PAllen

22 
2,481 
First of all, I'm not sure where to post this.
Now, I am reading some lectures about relativity, I came quite far...

Feb411 11:04 AM
Wotso

11 
1,145 
Given an antisymmetric tensor
T^{ab}=T^{ab}
show that
T_{ab;c} + T_{ca;b} + T_{bc;a} = 0
If I...

Feb411 09:09 AM
Naty1

10 
3,186 
what is time?
and how is space wind to it?

Feb411 12:22 AM
nitin_zilch

0 
921 
Hi, I am learning SR and I need help to get the idea of relativity with two clocks.
Yet I can understand that two...

Feb311 08:29 PM
JesseM

373 
36,078 
If the warp drive is shut down either by its destruction or just plain turning it off, what happens? Does the vessel...

Feb311 06:28 PM
Nabeshin

4 
1,612 
Hey, so I have a question.
The equivalence principle, the way it has always been taught to me, states that the...

Feb311 04:25 PM
DaleSpam

10 
1,360 
Theory of relativity restricts the speed of causal influences to the speed of light. But is it a proven science fact...

Feb311 03:11 PM
Neandethal00

12 
1,694 
Imagine an electron in uniform motion moving at a speed near the speed of light.
Pictures I've seen of the electric...

Feb311 01:59 PM
Qreeus

7 
2,510 
I have been doing some study on the theory of relativity and it has got me thinking. We say that the Earth revolves...

Feb311 07:14 AM
D H

8 
2,156 
It is well known that the shape of soap bubbles is spherical because of the fact that a sphere is the leastarea way...

Feb311 01:00 AM
GrayGhost

6 
1,006 
I have another problem that I am stuck on.
Show that a timelike vector cannot be orthogonal to a null vector.
...

Feb211 05:05 PM
purakanui

2 
3,085 