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Feb2313 08:40 AM
ZapperZ

1 
42,769 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,409 
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 
1,046 
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 
1,226 
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 
3,024 
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 
1,123 
Hi, I've begun learning about General Relativity, though I've already had some exposure to differential geometry.
...

Jan912 09:44 PM
PhizzyQs

4 
1,692 
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 
1,508 
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 
1,641 
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 
2,810 
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 
5,215 
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 
1,279 
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 
1,920 
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 
1,193 
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 
1,306 
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 
1,304 
Gravitational waves are generated when the mass quadrupole moment changes in time.
We also know motion of mass...

Jan612 04:02 AM
timmdeeg

12 
1,944 
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 
1,659 
By SR, relativistic energy and mass are proportional to the Lorentz factor γ, therefore, grow to infinity for...

Jan512 10:57 PM
climatos

10 
1,666 
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 
1,974 
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 
1,654 
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 
2,543 
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 
3,577 
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 
3,460 
Does anybody kow about a good summary (online) of the singularity theorems?

Jan512 01:20 AM
tom.stoer

2 
1,189 
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 
4,104 
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 
861 
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 
895 
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 
1,094 
Hey,
I'm just curious, MOND (Modified Newtonian Dynamics) seems to have a character of field renormalization...

Jan312 03:32 PM
rorix_bw

6 
1,064 
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 
1,580 
does there exist an angular speed limit, just like we have 'c' in relativistic mechanics?
If Yes, How?
If No, Why?

Jan312 02:48 PM
phydev

3 
1,266 
how are scientists able to distinguish between photons?
Photons are smallest quanta of EM (electromagnetic)...

Jan312 03:20 AM
climatos

2 
790 
When 2 objects A,B are moving wrt to each other (lets say @0.86c)then from frame A if local time is 10 years then time...

Jan312 02:18 AM
Snip3r

5 
1,648 
Hi all,
I'm reading Sean Carroll's Space Time and Geometry and haven't figure out how equation 4.64 is derived,...

Jan212 03:46 PM
Bill_K

2 
1,860 
Hey everyone, I am reading a Schaum's Outline on Tensor Calculus and came to something I can't seem to understand. ...

Jan212 09:00 AM
atyy

19 
4,149 
I got the general form of a Lorentz transformation in a GR book,
{\textbf{x'}} = {\textbf{x}} +...

Jan212 08:14 AM
Chestermiller

4 
2,269 
Quick question about the EFE's. When writing the einstein tensor G_{\mu\nu}=R_{\mu\nu}\frac{1}{2}Rg_{\mu\nu}, and...

Jan112 06:24 PM
unchained1978

2 
957 
I know hyberbola in spacetime diagram is that curvelike line below the light cone much like the bottom of a bath tub....

Jan112 05:09 PM
PeterDonis

6 
1,170 
I don't really know much about GR, but I was just wondering about this theoretical question. I am asking this,...

Jan112 05:06 PM
DaleSpam

9 
1,530 
I am curious about time dilation of atomic clock positions on and in the Earth. If you had a long tube going through...

Jan112 02:55 PM
pervect

21 
1,932 
Micro black holes should in principle be observable by emitting Hawking radiation. However, as this takes place...

Jan112 08:02 AM
timmdeeg

4 
1,179 