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Feb2313 08:40 AM
ZapperZ

1 
42,765 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,406 
i know those type of question are posted every day but it is short:
one twin is on a spaceship and the other on a...

Jul1906 07:09 PM
yogi

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1,732 
Is it justified to state that GR is "just" a geometrical theory to calculate the paths of objects in spacetime?
...

Jul1706 06:49 PM
pervect

3 
1,732 
Given a metric of the form
ds^2 = A(r) dt^2 + B(r) dr^2 + C(r)^2 (d\theta^2+sin^2\theta d\phi^2 + sin^2\theta...

Nov2610 02:54 PM
pervect

3 
1,732 
I'd be very happy if you'd answer this, and I'm looking more for the effect of gravity on time, rather than speed.

Apr2405 01:29 PM
Mortimer

5 
1,731 
I can't understand how the D'Alembertian x 4vector Vector potential = mu x 4vector J
Have
...

Mar3007 05:00 PM
Thrice

2 
1,731 
Although I do have a degree in chemical engineering, I am studying relativity/cosmology on a beginning level just as a...

Feb412 12:20 PM
Nugatory

10 
1,731 
Why is it that when describing time dilation, we say that the object (the thing observed) slows down relative to the...

Dec1612 06:04 AM
ghwellsjr

20 
1,731 
Yes, general relativity is out of my depths for now. Now I've often seen drawings of a gravitational source...

Dec2407 02:14 AM
pervect

2 
1,730 
I was wondering if anyone had an explicit form of the hamiltonjacobi equations for GR.
I had a little attempt myself...

Jan2908 11:16 PM
shoehorn

1 
1,730 
I have recently attempted quantifying relativity of simultaneity and I was wondering if my attempt has been...

Jul1212 03:31 AM
harrylin

13 
1,730 
Hi everyone, I am looking into relativity as preparation for university and I was wondering if anyone could help me...

Aug1311 07:01 AM
jimbobian

4 
1,730 
I have a question concerning the treatment of black holes in General Relativity. As I understand it, the force of...

Dec803 09:48 AM
Ambitwistor

9 
1,729 
Do you think that the involvement of photons in the derivation of the fundamental equations of relativistic dynamics...

Feb1306 07:48 AM
jtbell

4 
1,729 
Will the image of an object inside a gravitational lens, though on the side of the lens that is facing us, be...

Dec2206 08:40 PM
Chris Hillman

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How do we formulate the two body problem in Gr. Also if possible how do we solve it, or approximate said solution?

Jul807 12:03 PM
pervect

5 
1,729 
I've read that in GR, gravity isn't considered to be a force, or that it's considered to be a fictitious force because...

Sep1307 02:08 AM
rcgldr

5 
1,729 
The gravitational force is zero at the center of a planet, but the GPE is at a peak minimum (most negative). What...

Apr709 10:21 AM
rcgldr

4 
1,729 
Hi,
What are the weaknesses of Einstein's GR ?
Why people are trying to construct GR from field theoretical point...

Oct809 05:27 PM
Naty1

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1,729 
When you are in a box it is difficult to know the difference between if the box is accelerating in space or you are...

Feb2210 09:10 PM
gonegahgah

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is it correct to state that all the clocks of a given inertial reference frame, synchronized in accordance with...

Jul2506 02:43 PM
Robert.Hipple

2 
1,728 
Einstein v. Wheeler's Black Holes
John Wheeler who died earlier this month (13 April) not only coined the term ...

Apr2508 05:32 AM
pmb_phy

3 
1,728 
I am having problems with this presentation of the train thought experiment. I actually think it's incorrect, but I'm...

May210 11:54 AM
Jerbearrrrrr

2 
1,728 
Suppose I hold a pencil by its tip and turn it around 20°, around the axis which goes through the pencil's length. The...

Nov310 09:12 AM
ghwellsjr

16 
1,728 
Hi,
I've heard it said that for Schwarzschild spacetimes, then the coordinate 'r' is an affine parameter for radial...

Feb611 04:07 AM
LAHLH

8 
1,728 
After recently seeing Brian Greene's "Elegant Universe," I was struck by an idea  maybe not an original idea, but an...

Dec603 03:53 PM
Ambitwistor

1 
1,727 
two identical ships launch on parallel paths r distance apart. the are completely alone ]. once they reach some...

Apr411 11:46 PM
ghwellsjr

9 
1,727 
Hi there, Physics lovers!!
I've got some questions for you!!
Denoting by
(1)...

Apr2111 01:37 AM
MManuel Abad

2 
1,727 
I'm trying to use the equations on this page and I have solved the following. Is it correct?
...

Aug411 03:54 AM
randombill

1 
1,727 
Curious
Why does the equivalence of mass/energy involve the speed of light at all?
Is it because Einstein...

Jan1912 05:30 PM
Necrostate

13 
1,727 
Hello,
I would be interrested in building a list of things moving close to the speed of light.
This list would...

May812 01:43 PM
lalbatros

14 
1,727 
Forgive me if I'm being naive or if this has been answered before, but, I was wondering if someone can explain to me...

May209 04:02 AM
JesseM

8 
1,726 
hi............
In the twin paradox, we consider that one of the twins went out of the surface of earth...

Nov2811 12:24 PM
tom.stoer

12 
1,726 
If someone leaves on a spaceship from Earth at near the speed of light, the clock on the spaceship will appear be...

Dec1203 09:58 AM
DW

3 
1,725 
Say we have 2 bodies of m1 , m2 .
The distance between them is
a) r1 Ma=m1+m2
b) r2>r1 Mb=m1 +m2
In...

Sep1407 09:37 PM
pervect

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1,725 
A.A.Logunov, M.A.Mestvirishvili, Yu.V.Chugreev
THE EQUIVALENCE PRINCIPLE...

Jan2908 01:52 AM
J.F.

0 
1,725 
I was just rereading some of Hawking's writings, and apparently he is fairly stong supporter of a quantum theory of...

Oct1009 11:44 AM
Jonathan Scott

11 
1,725 
The subject of time dilations has always fascinated me. Sometimes the thought experiments can get confusing but there...

Nov1011 08:11 PM
nhmllr

4 
1,725 
I had 1 year ago a little discussion with DaleSpam about the short Lorentz derivation (triangle) if a photon alone...

Apr1613 06:38 PM
digi99

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So my physics teacher has been trying to explain magnetic forces in terms of electric forces and relativity but I'm...

Mar2512 09:40 AM
Naty1

5 
1,724 
Hello All I'm new to the forum and have a question.
I was looking at the time dilation function and noticed that...

Aug1111 05:14 PM
Ossama

9 
1,723 