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Feb2313 08:40 AM
ZapperZ

1 
37,474 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,210 
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 
566 
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 
291 
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 
305 
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 
373 
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 
579 
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 
340 
Never mind. Please delete this post

Mar1714 11:35 PM
bcrowell

1 
278 
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 
955 
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 
411 
This paper discusses the Bell spaceship paradox:
Petkov, "Accelerating spaceships paradox and physical meaning of...

Mar1714 12:34 PM
PeterDonis

7 
361 
As I've red, different points on the rotating disk, or rotating object have different velocities and so they should...

Mar1714 12:13 PM
ghwellsjr

3 
368 
I'm trying to understand inflation (in the cosmic sense). I know that ultimately that's a subject that involves both...

Mar1714 12:11 PM
PeterDonis

1 
289 
I am wondering how big the local coordinate charts in a coordinate atlas of General Relativity can be. Is it just a...

Mar1714 08:51 AM
DaleSpam

3 
272 
I was wondering since it is usually foliated into 2spheres and these are not themselves parallelizable(only the...

Mar1614 03:48 PM
TrickyDicky

6 
388 
Let's say we have a long cylinder and two pistons inside the cylinder, and some vapour between the pistons.
Now we...

Mar1614 11:14 AM
yuiop

24 
819 
I see a number of gravitational wave analytic solutions with the metric given in terms of Rosen coordinates. I have no...

Mar1614 05:32 AM
Bill_K

5 
390 
Hi guys, this is my first post, I'm a newbie regarding physics and relativity so I hope you can help me here.
I've...

Mar1514 10:36 PM
gravuniverse

41 
1,280 
Perhaps I am redshifted, but I just saw a video demonstrating space/time as a loaf of bread and depending on how it...

Mar1514 11:38 AM
yuiop

10 
519 
Einstein defined truly or absolutely synchronous clocks as follows:
"The simultaneity of two definite events with...

Mar1414 11:57 PM
pervect

1 
287 
Hi when trying to derive this equation, i am stuck on:
=\frac{\partial \gamma^{\nu}(x)}{\partial x^{\mu}} +...

Mar1414 08:17 PM
nuclearhead

8 
1,149 
In the discussion of a new FAQ entry on the Bell spaceship paradox, the following paper came up:
Jerrold Franklin,...

Mar1414 12:22 AM
bcrowell

15 
663 
I am having a hard time understanding a scenario that I have not found discussed elsewhere. It has to do with...

Mar1314 09:55 PM
DaleSpam

8 
440 
The title says it all, really. Are we able to describe GR in terms of a Graded Time Dilation Field in Euclidean...

Mar1314 02:49 PM
PAllen

36 
1,184 
One of the properties of the unique LeviCivita connection is that it preserves the metric tensor at each point's...

Mar1314 01:00 PM
TrickyDicky

94 
2,336 
Hello,
##E_{tot}^2=(pc)^2+(m_0 c^2)^2## works fine for mass ##m_0## moving with relativistic speeds. What if the...

Mar1314 09:17 AM
DaleSpam

33 
863 
In Schutz, the christofell symbols are dervied from applying the product rule to a vector in a curvillinear basis.
In...

Mar1314 01:39 AM
WannabeNewton

1 
371 
I think I am wrong in what I am about to say so I someone could explain relatively simply where I went wrong I would...

Mar1214 09:50 AM
Nugatory

1 
270 
I have always assumed once we pass through a black hole's event horizon, we can throw away the return ticket. But I...

Mar1214 08:53 AM
PAllen

1 
299 
Hello,
I am working on a project but I stuck at a point. I found that divergence of two objects are equal...

Mar1214 05:17 AM
crimsonidol

0 
228 
Well when I watch movies I see space time as 2d. But how do we see the space time from earth to a region lower than...

Mar1214 04:27 AM
A.T.

1 
272 
depending on your frame of reference, correct? If I am standing still, and at the same time (my time) shine 2...

Mar1214 02:32 AM
BruceW

13 
515 
Is there any way of man, in the distant future, bend space time in a way that it would propell something faster than...

Mar1114 10:34 PM
PeterDonis

3 
298 
So im trying to understand some of the ideas of relativity but there is one thing i don't get. I understand that if...

Mar1114 09:21 PM
abbott287

4 
321 
I am preparing a simple demonstration of gravity for a lay audience, inspired by this applet and the wellknown book...

Mar1114 09:14 PM
WannabeNewton

1 
275 
We have had a number of threads on how to synchronise clocks around a rotating ring. One method of doing this is to...

Mar1114 04:25 PM
yuiop

2 
293 
Hey, I read that if a fourvector is 'fourorthogonal' to a timelike four vector then it must be spacelike. I showed...

Mar1114 09:35 AM
Bill_K

1 
231 
i have the basic question of special relativity why time , length and mass is a function of velocity here? i may know...

Mar1114 09:04 AM
DaleSpam

9 
412 
If an electron is travelling at C/2, the Lorenz formula says that mass is about 1.15 me, do we get the value of KE...

Mar1114 07:39 AM
Dadface

20 
806 
I was reading a little about the behavior of noninertial frames in relativity, since I'm interested in knowing how...

Mar1014 10:30 PM
JVNY

61 
2,089 
Here for your consideration is a try at synchronizing clocks on a rim rotating at a constant angular velocity. It is...

Mar1014 10:16 PM
JVNY

69 
2,371 