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Feb2313 08:40 AM
ZapperZ

1 
42,469 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,118 
Do you know any book written by a great physicist where he talks about black holes? I always enjoy reading the more...

Feb1911 12:32 PM
JesseM

1 
697 
Seeing the horn (which is like a water vortex) of General Relativity, it seems that the position of the Sun is at the...

Feb1911 11:32 AM
JesseM

10 
1,446 
GR predict that a photon climbing in the earths gravitational field will lose energy and will consequently be...

Feb1911 10:19 AM
Jonathan Scott

3 
1,459 
I am going to talk about the famous trainplatform experiment where two lightnings strike both ends of the platform...

Feb1911 09:13 AM
Mohammed_I

2 
2,713 
Based on the wiki article:
http://en.wikipedia.org/wiki/Einstein%E2%80%93Cartan_theory
Cartan gravity is not...

Feb1911 05:52 AM
tom.stoer

7 
3,402 
Hi,
I have a question which was raised after reading the article "Derivation of the string equation of motion in...

Feb1911 03:10 AM
haushofer

16 
2,366 
In Stephen Hawkins videos he told that time was affected by mass. Why would that be? Can anyone tell?

Feb1811 09:41 PM
JesseM

7 
1,334 
Hello! This is my first post on this forums, always been here since a year back through google while looking for some...

Feb1811 01:46 PM
tinytim

5 
1,636 
I was discussing with my E&M professor the idea of faster than light information exchange, which of course we found to...

Feb1811 01:36 PM
Phrak

15 
1,869 
Would General Relativity predict that two initially parallel light beams will converge due to their energy curving...

Feb1811 04:45 AM
johne1618

5 
2,190 
Hi.
If Newtons theory of gravity was changed  so that gravity is considered to propagate at the speed of light AND...

Feb1711 04:32 PM
Hernik

8 
1,051 
For E=mc2
I'm having trouble understanding intuitively how every kilogram of m conveniently is associated with a...

Feb1711 12:49 PM
JesseM

6 
1,418 
ok, i just can't figure this one out.
you have heard of the example of the 2 wires, and depending on their...

Feb1711 11:19 AM
JesseM

1 
1,254 
In A First Course in General Relativity, the use of the weak field approximation is confusing to me. I constantly get...

Feb1611 08:58 PM
WannabeNewton

9 
1,353 
Most people on this forum know the basic theory of black hole formation. When a massive star runs out of fuel there is...

Feb1611 11:27 AM
Naty1

5 
1,950 
Pretty basic relativity questions. Have any of you read Ender's Game by Orson Scott Card? Great book by the way. ...

Feb1611 11:18 AM
JesseM

10 
6,544 
Hello, I am aware that this question was the subject of a topic on this site, but it did not fully answer my question....

Feb1611 08:47 AM
Naty1

5 
2,248 
This might be a stupid question..
Why does curved spacetime cause objects with mass to accelerate towards each...

Feb1611 08:35 AM
Naty1

20 
3,276 
The Schwarzschild solution to the field equations is a vacuum solution for a spherically symmetric mass and provides...

Feb1611 06:00 AM
Mentz114

7 
1,284 
My question deals with how the mass of light effects its speed. First question, does light actually have mass? If so...

Feb1611 04:00 AM
ZapperZ

15 
2,311 
Who are the authors of relativity theory? From Wikipedia:
" Tesla also believed that much of Albert Einstein's...

Feb1511 10:21 PM
PAllen

36 
5,295 
hey,
I heard about improper Lorentz transformations, but I did not really understand what they are. I just know...

Feb1511 02:24 PM
the_house

1 
1,770 
Quantum Entanglement allows spatially separated entangled particles to have impact on each other instantly (overcoming...

Feb1511 12:44 PM
Mentz114

5 
1,596 
Hi everyone,
Today a strange thought came into my mind. We know that the mass of an object increases as it gets...

Feb1411 05:50 PM
schonovic

63 
7,928 
OK, i have a final coming up, and i need a little help.... i need to know how and why an object moving faster acquires...

Feb1411 04:29 PM
Neandethal00

19 
4,580 
Alice is freefalling towards the event horizon (EH) of a black hole (BH) large enough such that local tidal forces...

Feb1411 03:17 PM
DrGreg

15 
1,675 
A tachyon is a hypothesized particle that has imaginary mass (imaginary numbers) and moves faster than light speed. I...

Feb1411 01:52 AM
Wolf5370

19 
2,480 
Greetings everyone,
I understand the derivation of the Lorentz transformations, and have not had trouble applying...

Feb1311 03:50 PM
phyti

12 
1,361 
I don't think this should be a very difficult question for people who are used to working with tensors, but I'm new to...

Feb1311 02:01 PM
Fredrik

28 
1,848 
hi,
I was going through the problem when light is bent by gravity. The newtonian result is half of result...

Feb1311 12:48 PM
Cleonis

4 
1,271 
How is Lorentz invariance handled in GR? I know that there is no global Lorentz invariance in GR, instead it only...

Feb1311 06:55 AM
TrickyDicky

56 
4,681 
An observer (in zero gravity) witnesses two parallel but widely separated beams of light that are transmited at the...

Feb1211 05:47 PM
harrylin

77 
8,010 
The Lorentz transformation are given by (see the attachment)
x'=(xvt)/√(1v^2/c^2 )
t'=(tvx/c^2)/√(1v^2/c^2 )...

Feb1211 05:38 PM
harrylin

115 
8,989 
how the particle moving at a speed near to that of light interact to it's surrounding,considering the very fact of...

Feb1211 11:20 AM
DaleSpam

23 
1,967 
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 
1,019 
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 
22,633 
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 
1,278 
Why does General Relativity breakdown at Plank Temperature?

Feb1111 12:49 PM
bcrowell

1 
1,098 
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 
843 
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 
1,611 