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Feb2313 08:40 AM
ZapperZ

1 
41,523 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,155 
Is there any relationship between the Lie (\pounds) and covariant derivative (\nabla)?
Say I have 2 vector fields...

Dec611 09:01 AM
nickj1

9 
9,805 
So, I've never been able to understand where the extra mass comes from when an object is traveling near the speed of...

Dec511 08:48 PM
PAllen

19 
2,998 
Space time Geometry and GR, taken from lecture notes
http://www.mth.kcl.ac.uk/courses/cm334.html
...

Dec511 12:51 PM
atyy

1 
1,522 
I have read:
F=q(v*B)
where q=charge of the particle
v=velocity of the charge particle
...

Dec511 08:57 AM
jfy4

3 
1,295 
HI all
There is smth I dont understand in building initial data for BH
The equations everybody uses uses spacetime...

Dec511 08:53 AM
PeterDonis

11 
1,877 
In another thread here,
http://www.physicsforums.com/showthr...=548148&page=3,
post #36,
Peter Donis posted...

Dec511 07:45 AM
Naty1

5 
1,222 
Ok. I understand that the set of Lorentz boosts and space rotations is equivalent to the set of Lorentz...

Dec511 02:02 AM
Fredrik

4 
1,826 
In a thread a while back, Mentz114 posted a Painleve chart for FRW spacetime; here's the link to the post:
...

Dec411 10:31 PM
PeterDonis

7 
1,527 
Hey, this is my first post of many as I have hundreds of questions!
As speed of light is a constant, does it travel...

Dec411 06:48 PM
ghwellsjr

14 
2,826 
There's something called "rest mass" that is the mass of a body in "rest". But since rest is relative it is impossible...

Dec411 04:08 PM
jtbell

2 
1,558 
I (think I) understand that:
1. With the Schwarzschild metric, the ratio of proper time to coordinate time...

Dec411 04:01 PM
A.T.

7 
1,884 
kindly be descriptive

Dec411 12:00 PM
rbj

10 
10,227 
I wanted to understand something about Inertial frames especially as they are talked about in SR.
It appears that...

Dec411 08:27 AM
atyy

6 
1,163 
Would it be the rotational speed increasing or the speed at which the Earth revolves around the Sun?
I take it in...

Dec311 02:27 PM
Passionflower

7 
1,772 
Hi Everyone.
I have just created an animated video on Special and General Relativity, explaining how all the...

Dec311 02:12 PM
ghwellsjr

15 
2,723 
The poincare' group is the group of isometries of Minkowski spacetime, in a nutshell. In terms of an actual physical...

Dec211 10:49 PM
matumich26

5 
1,806 
I'm still struggling with spacetime curvature. I want to know about the spacetime intervals in the following scenario:...

Dec211 06:42 PM
gabeeisenstei

2 
1,742 
I have a question about measuring the speed of light. As I understand it is done by sending photons from A at time t1...

Dec211 02:11 PM
ghwellsjr

9 
1,494 
The 4velocity of a photon is undefined, so does that mean the velocity of a photon is undefined?
What is the...

Dec211 01:51 PM
D H

80 
5,907 
Assume we are on a non rotating planet and shoot a rocket straight with a given velocity (smaller than the escape...

Dec211 11:03 AM
Passionflower

4 
1,796 
If I bend a paper, it doesn't change the things written on it.
If gravity is bent space(time), we shouldn't be able...

Dec211 04:47 AM
eloheim

19 
2,710 
How much experimental evidence is there that the speed of light stays c between a source and target moving wrt to...

Dec211 02:58 AM
PhilDSP

3 
1,339 
Hello PF community!
I'm having trouble with what strikes me as an inconsistency within conservation of energy,...

Dec111 11:28 PM
n+1

4 
1,694 
SRT = the theory of special relativity
I can't find for myself what is wrong with this ?
A...

Dec111 11:25 PM
digi99

45 
6,291 
I got confused.. XD
"Under Einstein's theory of relativity, an object accelerated close to the speed of light gains...

Dec111 11:23 PM
LGram16

4 
1,353 
Hi! Need some help here.
Are the effects of general relativity reciprocal in two reference frames? Let's say for...

Dec111 09:48 PM
blueberrynerd

3 
1,322 
Greetings,
I have been trying to teach myself SR and GR and have been going the Bernard Schutz's First Course in...

Dec111 07:58 PM
HJ Farnsworth

7 
2,140 
First of all, a hearty hello to everyone! New poster on this board, though I've been reading this forum quite a bit...

Dec111 07:39 AM
clem

2 
1,226 
hi there............
We say that the speed of light is constant when seen from any frame of refrence because the...

Dec111 06:23 AM
A Dhingra

11 
1,800 
Suppose I construct a metal triangle in flat space the sum of the interior angles will be 180°. If I then move the...

Dec111 01:23 AM
pervect

2 
1,457 
A stationary observer sees a moving train going at .6c.
Does the moving train see the stationary observer going .6c...

Dec111 12:31 AM
ghwellsjr

3 
1,346 
The faster you travel the slower time travels. But instead could we be thinking in terms of it taking longer for...

Nov3011 02:05 PM
Matterwave

2 
1,551 
While gravitational redshift refers to what is seen, gravitational time dilation refers to what is deduced to be...

Nov3011 12:15 PM
enfield

3 
1,889 
I read that an objects mass increases as it approaches the speed of light and that this was the reason why anything...

Nov3011 11:56 AM
DrStupid

8 
2,351 
So imagine that time is very slow, like 1 meter per second. Yes I know this is impossible, but I'm tired of space...

Nov3011 08:33 AM
ghwellsjr

21 
2,628 
Hi everybody!
what happens if an electron passes by with a speed of, say, 99.999999999...% of the speed of light...

Nov3011 07:37 AM
Naty1

59 
6,726 
I'm familiar with space and time together being 4 dimensions and that mass causes a curvature in this spacetime.
...

Nov3011 04:33 AM
A.T.

15 
2,354 
Block Time in relativity where past, present and future exist all the time seems to be in conflict with quantum...

Nov3011 04:00 AM
stglyde

109 
9,318 
I have been reading Einsteins Relativity and a simple concept in special relativity is tripping me up. I have heard...

Nov2911 10:13 PM
ghwellsjr

3 
1,167 
Are there any exact solutions known for a black hole in a universe which is NOT asymptotically flat?

Nov2911 09:17 PM
Passionflower

2 
1,041 