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Feb2313 08:40 AM
ZapperZ

1 
41,022 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
40,679 
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 
1,158 
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 
1,766 
Hi Everyone.
I have just created an animated video on Special and General Relativity, explaining how all the...

Dec311 02:12 PM
ghwellsjr

15 
2,714 
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 
1,800 
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 
1,735 
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 
1,490 
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 
5,884 
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 
1,792 
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 
2,700 
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 
1,334 
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 
1,691 
SRT = the theory of special relativity
I can't find for myself what is wrong with this ?
A...

Dec111 11:25 PM
digi99

45 
6,280 
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 
1,330 
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 
1,317 
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 
2,132 
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 
1,222 
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 
1,786 
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 
1,454 
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 
1,344 
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 
1,548 
While gravitational redshift refers to what is seen, gravitational time dilation refers to what is deduced to be...

Nov3011 12:15 PM
enfield

3 
1,883 
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 
2,348 
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 
2,607 
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 
6,687 
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 
2,345 
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 
9,272 
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 
1,165 
Are there any exact solutions known for a black hole in a universe which is NOT asymptotically flat?

Nov2911 09:17 PM
Passionflower

2 
1,037 
Assuming a spacecraft had a propulsion system and sufficient fuel, what stops it from reaching the speed of light and...

Nov2911 11:50 AM
FlexGunship

3 
1,292 
If a spacecraft were travelling at the speed of light (OK, forget the difficulties for now) relative to an observer on...

Nov2911 09:10 AM
PAllen

17 
2,993 
In working with these vierbein fields I've come across these terms such as e^{aμ}e^{μ}_{a} where the e's are vierbein...

Nov2911 02:13 AM
dextercioby

7 
1,885 
Hello.
This is probably a stupid question, but I'm very confused, so any help would be much appreciated!
If...

Nov2811 02:21 PM
DrGreg

12 
1,468 
hi............
In the twin paradox, we consider that one of the twins went out of the surface of earth...

Nov2811 12:24 PM
tom.stoer

12 
1,630 
Does the lambda symbol \Lambda_{\nu}^{\mu} refer specifically to the Lorentz transformation matrix or to any...

Nov2811 06:08 AM
Fredrik

1 
2,353 
The depiction of time dilation that is typically used to describe the situation,
shows the stationary photon clock,...

Nov2811 02:41 AM
ghwellsjr

26 
2,985 
Hi, and thanks for making such a great forum!
My question is as the title proposes. Would Einstein's Theory of...

Nov2711 06:19 PM
nitsuj

6 
1,306 
how is relativity theory applied to gps?
thanks

Nov2711 05:17 PM
surd100

8 
2,461 
ok, if when we look at a planet that is say 100000 light years away, and we can see it emitting light, and that light...

Nov2711 04:28 PM
ianpr

14 
1,667 
I know I spelled dilated obscenely wrong in the title. I'm sorry!
==
Is the connection that in both time...

Nov2711 04:22 PM
pervect

4 
1,081 
If one wants to calculate the elapsed time from the perspective of an object A moving at velocity, v, for time, t,...

Nov2711 01:53 PM
enfield

10 
1,801 