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Feb2313 08:40 AM
ZapperZ

1 
37,401 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,157 
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 
380 
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 
1,186 
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 
382 
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 
287 
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 
1,170 
Can a magnetic field bend spacetime?

Mar2714 01:34 AM
Drakkith

1 
334 
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 
263 
In an old (2008) thread, DrGreg posted this transformation from a Minkowski chart to a Rindler chart
...

Mar2614 02:24 PM
PAllen

16 
445 
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 
321 
I am using a wikipedia page, Derivation of the Lorentz transformations and a lot of historical papers. To follow...

Mar2614 07:13 AM
ANvH

5 
299 
The three main effects of SR occur in inertial frames and change the description of spacetime relative to a...

Mar2514 12:32 PM
A.T.

8 
344 
Hi there,
I think I understand how, using Lorentz transformations, I can find relative speeds of objects within...

Mar2514 12:31 PM
Nugatory

3 
310 
Two questions, based on the same situation: in ...

Mar2514 10:27 AM
nomadreid

2 
247 
Hi All
Gravitation seems very interesting field to me. One of the most mysterious field of studies, which is having...

Mar2514 01:40 AM
Sethi

0 
276 
Biking at near the speed of light
If a biker is going at 0.99c, an observer standing still would notice his...

Mar2414 07:48 PM
jartsa

38 
915 
https://www.youtube.com/watch?v=c3fJRRCAIdk This is a video of the 'barking dog' chemistry experiment captured with a...

Mar2414 06:57 PM
russ_watters

1 
234 
Reading over Alcubierre's paper on his "warp" drive (http://arxiv.org/abs/grqc/0009013), the metric in equation 3...

Mar2414 11:55 AM
PAllen

2 
376 
Greetings,
I've been learning about special relativity and most of the learning media included a part of general...

Mar2414 11:46 AM
drichard

3 
313 
I just watched a video that kind of warped my understanding of time dilation. It said that not only would time appear...

Mar2414 06:33 AM
ghwellsjr

10 
645 
This is a puzzle based on a purported "refutation of GR" on this webpage, which is also the subject of a subthread in...

Mar2314 02:42 PM
DaleSpam

92 
8,136 
Looking at the Einstein equation, stresses can cause a deformation of space time.
This link here...

Mar2314 08:36 AM
Vanadium 50

7 
374 
I was just wondering what would the definition of the inertial frame be, since as I've understood the description it...

Mar2214 11:01 AM
A.T.

3 
361 
Could there be an absolute 'state of reference' somewhere in the universe, perhaps at the location of the original...

Mar2214 05:56 AM
DaleSpam

135 
2,848 
Since the speed of light is a constant, no matter what location from which a search of the universe is made, matter...

Mar2114 07:02 PM
PAllen

5 
347 
∇_{\mu}g_{\alpha\beta}=0 is the metricity equation (∇ the covariant derivative).
However, I wondered whether also...

Mar2114 06:52 PM
dextercioby

4 
300 
So I created an account here just so I could ask this burning question. I keep looking online and through other...

Mar2114 04:07 PM
pervect

12 
697 
I think that is a fundamental question of why we need Tensor when dealing with GR?
Quoting from the text book...

Mar2114 01:17 PM
WannabeNewton

12 
615 
The stress energy momentum tensor of the Einstein field equations contains multiple density terms such as the energy...

Mar2014 07:46 PM
pervect

4 
311 
There are various explanations for Thomas precession in the literature and I would like to come to a deeper...

Mar2014 05:20 PM
WannabeNewton

70 
3,091 
I've been studying the Einstein field equations. I learned that the Ricci curvature tensor was expressed as the...

Mar2014 02:01 PM
spacetime

7 
377 
What is the gravitational binding energy in GR in the spherically symmetric case?
I calculate...

Mar2014 11:36 AM
pervect

4 
318 
Consider two points A and B (Fig.1) at rest in S frame having a distance L0 between them (a long scale may be imagined...

Mar2014 09:38 AM
Nugatory

11 
562 
Hi,
While reading Sean Carroll's book, I came across the following statement:
Okay so this has me confused....

Mar1914 06:15 PM
maverick280857

2 
288 
I'll ask that you forgive me if my question seems to "basic" or simple for some of the more professional posters. I...

Mar1914 03:15 PM
A.T.

3 
298 
Hi guys, I'm reading a text regarding different possible ways of synchronizing clocks in an inertial frame, so maybe...

Mar1914 12:43 PM
DaleSpam

7 
367 
At v = c, time (hence physics) stands still.
You can never reach c, but lets say near enough.
Therefore if you...

Mar1814 03:39 PM
sshai45

15 
568 
Let's say we have a metro tunnel that is a circular loop with 1 m x 1 m rectangular cross section. The tunnel is 100...

Mar1814 10:18 AM
DaleSpam

3 
336 
Never mind. Please delete this post

Mar1714 11:35 PM
bcrowell

1 
275 
Hello all,
In Carroll's on page 109 it is pointed out that for derivation of the geodesic equation, 3.44, a...

Mar1714 03:37 PM
victorvmotti

26 
949 
While Planck time is usually regarded as the shortest unit of time, isn't the shortest unit of time that can exist is...

Mar1714 01:58 PM
mfb

5 
404 