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Feb2313 08:40 AM
ZapperZ

1 
42,473 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,128 
Hi everyone:
Do event horizons appear to be surrounded by all the stuff that has ever fallen in? As I understand...

Jan1212 04:27 PM
tom.stoer

38 
3,922 
A quote from an old thread reads "Energy is the time component of the momentum 4vector"
That quote came from a...

Jan1212 02:10 PM
elfmotat

6 
1,155 
Anybody could explain me the difference between tidal forces and gravitational waves?
My question emerges from the...

Jan1112 08:49 AM
timmdeeg

11 
1,805 
In his book 'Concepts of MODERN PHYSICS', Chapter 1, Section 1.7, page# 22to 24, Arthur Beiser tries to derive an...

Jan1112 08:11 AM
PAllen

12 
1,495 
I'm getting myself confused here. If my relativistic Lagrangian for a particle in a central potentai is
L =...

Jan1112 07:58 AM
maverick_starstrider

3 
1,178 
*** Had a chance to rethink this and still believe it makes sense, so I need somebody to put me straight :) ***
...

Jan1112 02:54 AM
Mike Hobbs

26 
4,011 
Suppose two black holes graze one another in a high speed encounter. The collision is glancing such that the event...

Jan1012 11:16 PM
Antiphon

2 
1,131 
Hi Guys, Im just new to SR & GR. I learned about Lorentz contraction and time dilation, but they dont make sense when...

Jan1012 09:55 PM
ghwellsjr

45 
5,653 
Hello! I ask this question in this forum because I wish to be given a general explanation.
Hope it is OK
given...

Jan1012 06:02 PM
Bill_K

1 
824 
I was just playing around with thoughts while laying in bed, and I need confirmation or rejection of a random idea...

Jan1012 04:14 PM
D H

34 
5,517 
Consider the variational principle used to obtain that in the vacuum the Einstein tensor vanish.
So we set the...

Jan1012 03:57 PM
Bill_K

1 
791 
Hi all, this is not a HW problem but one I made up myself, (so you won't find it in any txtbooks or solutions etc.)....

Jan1012 03:41 PM
ghwellsjr

4 
1,025 
Has anyone worked all the way through D'Inverno Chapter 19 Problem 19.5?
I've had a good thrash at it  it is quite...

Jan1012 05:48 AM
TerryW

2 
1,210 
Hi,
Just a quick question I can't get my head around.... Say I have a big planet sitting in intergalactic space and I...

Jan1012 03:15 AM
harrylin

23 
2,982 
If two objects move away from each other both at the speed of light, after 1 second will they be approximately 372,000...

Jan1012 12:32 AM
my_wan

6 
1,110 
Hi, I've begun learning about General Relativity, though I've already had some exposure to differential geometry.
...

Jan912 09:44 PM
PhizzyQs

4 
1,671 
Einstein is riding the beam of light away from the clock tower so the hands of the clock don't move. Suppose the...

Jan912 05:41 AM
harrylin

5 
1,481 
Hello
i studied Sadri Hassani az mathematical physics book.
if i want to learn topology (( for general relativity ))...

Jan812 03:19 PM
George Jones

4 
1,622 
I've been trying to find out what the definition of negative pressure in the context of General Relativity. There are...

Jan812 10:44 AM
timmdeeg

20 
2,740 
Hello,
I thought of asking would someone know what is the correct thinking here...
A body is thrown upwards, its...

Jan812 08:42 AM
Qreeus

46 
5,177 
The stressenergy tensor is associated to a volume density and flux in 4spacetime and the Einstein tensor seems to...

Jan712 02:39 PM
TrickyDicky

8 
1,268 
Hi, I'm kind of a noob when it comes to physics so I just have to ask. Me and my friends are kind of in a pickle, so...

Jan612 03:14 PM
pervect

13 
1,888 
I like astrophysics,so i read books relating to it.I am also determined to make my career in the same.At present i am...

Jan612 09:06 AM
ghwellsjr

1 
1,182 
I had this doubt studing GR, but lets consider SR for semplicity,
where g_{\mu\nu}=\eta_{\mu\nu}the geodesics are...

Jan612 07:45 AM
Mentz114

5 
1,289 
There is a thought experiment pertaining to general relativity that involves a signal traveling from the front to the...

Jan612 05:56 AM
ericqb

3 
1,294 
Gravitational waves are generated when the mass quadrupole moment changes in time.
We also know motion of mass...

Jan612 04:02 AM
timmdeeg

12 
1,905 
E=MC^2
Here,
say we want to find the energy of a single photon.
that means,
mass of photon x speed of light...

Jan612 12:33 AM
jedishrfu

9 
1,644 
By SR, relativistic energy and mass are proportional to the Lorentz factor γ, therefore, grow to infinity for...

Jan512 10:57 PM
climatos

10 
1,632 
I've posted on this forum before and carefully read the answers, but I'm still confused... Also, I'm familiar with the...

Jan512 09:54 PM
ghwellsjr

13 
1,942 
Thank you in advance for reading this and hopefully answering my questions.
I've spent about two hours or so now...

Jan512 06:47 PM
pervect

4 
1,636 
It's fairly easily to visualize space bending as a result of the mass of an object, and that the bending of space is...

Jan512 07:52 AM
tgm1024

19 
2,497 
How would you go about teaching relativity to someone who refuses to take anything on faith or argument from...

Jan512 07:38 AM
DaleSpam

37 
3,528 
I just got my first official introduction to relativity in my textbook (I'm equivalent to a high school senior...

Jan512 04:43 AM
PrincePhoenix

35 
3,398 
Does anybody kow about a good summary (online) of the singularity theorems?

Jan512 01:20 AM
tom.stoer

2 
1,180 
Let's say we have two clocks that are synchronous here on Earth.
One of the clocks is instantly transported to...

Jan512 01:06 AM
ghwellsjr

26 
4,018 
Hello
what is the meaning of covaraint derivative ?
where the ordinary derivative of a function whit respect to a...

Jan412 04:40 PM
Naty1

3 
854 
Hello everyone
Can some one please provide (a link to) the most rigorous proof of E_0 = mc^2?
Actually, I got stuck...

Jan412 02:50 PM
quZz

2 
887 
Increase in weight if an object is illuminated
Are there experiments which show that the weight of a body, with...

Jan312 10:40 PM
climatos

3 
1,083 
Hey,
I'm just curious, MOND (Modified Newtonian Dynamics) seems to have a character of field renormalization...

Jan312 03:32 PM
rorix_bw

6 
1,058 
Is it possible for a particle to exist according to one reference frame and simultaneously not exist according to...

Jan312 03:01 PM
pervect

7 
1,563 