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Feb2313 08:40 AM
ZapperZ

1 
42,482 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,139 
So i am working on a question, which is beyond my knowledge of Lorentz transformations and some help is greatly...

Apr814 06:33 AM
Fredrik

19 
729 
I'm currently going through my courses notes for relativity. We looked at Einsteins two postulates and then said that...

Apr714 08:36 PM
Nugatory

4 
315 
Hi guys, I was thinking about the relativistic effects a little bit, and I have a question regarding relative...

Apr714 07:00 PM
Andrew Mason

19 
758 
Sorry if this turns out to be a colossally stupid question. I'm a newbie.
But since light has a constant speed in...

Apr714 05:42 PM
Nugatory

2 
289 
consider a circular loop (a particle accelator). Suppose any particle moves their with speed ≈ c. Now let the radius...

Apr714 07:40 AM
georgir

3 
423 
Hey all,
I've been reading my fair share on physics and I would like to find a solution to a question that has been...

Apr614 07:42 AM
andromeda

11 
429 
Trying to see the logic in deriving length contraction and time dilation using the Lorentz transformations and inverse...

Apr514 02:15 PM
ANvH

43 
1,730 
What is the simplest derivation of the transformation rules for Maxwell's equations in special relativity?
I'm...

Apr514 02:14 AM
Fredrik

17 
2,123 
Hello again,
Two days ago, I started a thread asking about the same question more or less, and I was thinking that...

Apr414 11:26 PM
haruna

2 
329 
How can I explain to someone who has only high school level of education in physics, what is general and special...

Apr414 11:13 PM
micromass

29 
1,245 
I have a question pertaining to objects falling through the event horizon of a black hole.
It is my understanding...

Apr414 05:07 PM
Bill_K

3 
367 
I understand how contravariant 4vectors transform under a Lorentz transformation, that is:
##x'^μ=...

Apr414 07:03 AM
Rococo

23 
968 
...
Three scientists are familiar with Special Relativity and it's rules.
The three scientists decide to conduct...

Apr414 03:41 AM
Doc Al

11 
757 
Hi friends,
I was wondering about the following  in GR texts we always see these penrose diagrams and some line...

Apr314 05:20 PM
bcrowell

6 
444 
In popular perception of curved spacetime the metaphor of trampoline and a dimple on it is often used to explain...

Apr314 01:57 PM
DaleSpam

20 
1,109 
Hi guys. I was reading a paper in which a calculation was done to show that in Schwarzschild spacetime, if we...

Apr314 08:27 AM
PeterDonis

41 
2,650 
Hello to everybody,
the question seems trivial in my mind, yet, is it legal to say that there is not unique frame...

Apr214 06:02 PM
haruna

4 
421 
Hi all. we know that the rest is the mass of an object within a coordinate system which has zero velocity, but how...

Apr214 04:59 PM
Matterwave

2 
307 
I am a little confused about the Galilean transforms.
If I have t'=\gammat
Is t ALWAYS the frame of reference...

Apr214 09:05 AM
Nugatory

6 
464 
I was hoping someone could help me with a simple physics question I've been mulling over, I've failed to find an...

Apr214 06:07 AM
Nugatory

12 
750 
Hello All,
Sorry if my question seems to be elementary. I am trying to find out a little bit details of the Riemann...

Apr214 01:13 AM
Matterwave

3 
400 
Hi everybody,
As you know, the Einstein field equation
R_{μ\nu}  1/2Rg_{μ\nu} =κT_{μ\nu}
implies that at...

Apr114 11:31 PM
bcrowell

10 
623 
Hello,
I have a question, whether is possible to looking for Killing Vectors (KV) in this way (I know about...

Apr114 07:26 PM
WannabeNewton

4 
477 
Hi, I've heard and read that if someone was to fall towards a black hole, say feet first, they would undergo...

Apr114 06:23 PM
liron

7 
585 
I'm trying to work out:
(∇f)^2 (f is just some function, its not really important)
While working in curved...

Apr114 05:02 AM
TrickyDicky

7 
382 
Hi,
I've found geodesic equations for the metric:
\begin{equation}
ds^{2} = c^{2} \alpha dt^{2} + \frac{1}{...

Mar3114 10:35 AM
Bill_K

1 
358 
In an expanding universe that is modeled by the FRW metric we assume that scale factor of the "present epoch" is unity...

Mar3014 01:33 PM
victorvmotti

4 
402 
Hi All. Layman question.
In the twin's paradox, why one of the brothers is older when they meet again?. if movement...

Mar3014 05:05 AM
Nugatory

63 
6,178 
In Padmanabhan's Theoretical Astrophysics by defining a ratio for comparing gravitational potential energy with...

Mar2914 07:58 PM
bcrowell

9 
580 
Ok, I have an experiment, well actually it is more of a question than an experiment. I have a very elementary...

Mar2914 04:09 PM
delsaber8

15 
737 
I couldn't work out exactly where to post this. I've heard several times that QM and General relativity "contradict"...

Mar2914 11:22 AM
PeterDonis

2 
414 
So basically, my physics class has begun focusing on SR. And i just wanted to clarify something. I have been...

Mar2914 02:44 AM
ghwellsjr

6 
511 
v=? delta what/which X(distance) over delta what/which T(time)
http://en.wikipedia.org/wiki/Special_relativity

Mar2814 10:02 PM
Fredrik

21 
1,396 
Hello, Im a newguy here, so if my question dont belong to this section, please let me know.
My question:
In...

Mar2814 08:21 PM
bcrowell

5 
482 
Hello,
Im looking for some time dependent exact solution of Einsteins eqs. If Im right (if not please correct me)...

Mar2814 02:52 PM
Chestermiller

6 
425 
I know the reasons why the relativistic mass equation (M= gamma Mo) is out of favour with what seems to be a majority...

Mar2714 12:58 PM
DrStupid

37 
1,917 
Can a magnetic field bend spacetime?

Mar2714 01:34 AM
Drakkith

1 
400 
So the angular diameter distance is given by the angle it extends in the sky and its actual size x
d_A=...

Mar2614 02:38 PM
kuecken

0 
336 
In an old (2008) thread, DrGreg posted this transformation from a Minkowski chart to a Rindler chart
...

Mar2614 02:24 PM
PAllen

16 
621 
So I have just been introduced to indices, four vectors and tensors in SR and I'm having trouble knowing exactly what...

Mar2614 10:24 AM
vanhees71

5 
417 