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Feb2313 08:40 AM
ZapperZ

1 
40,714 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
40,363 
Suppose you have a spacetime with an observer at rest at the origin, and the surface at t = 0 going through the...

Apr1208 03:53 PM
lark

0 
1,938 
I've read Schwarzschild paper and I don't understand his conditions
"The solution is spatially symmetric with...

Apr1208 11:47 AM
tinytim

2 
2,136 
Can anyone tell me where can I get detailed derivation of PlanckEinstein Transformation of temperature in the...

Apr1208 09:11 AM
Frank Lampard

0 
1,691 
Why is Einstein's law of gravitation for empty space sometimes identified as Ricci tensor=0 instead of Einstein...

Apr1108 11:00 PM
snoopies622

5 
1,875 
i need some help here, say if there's a ship, no matter how it steers, it will always end up at the starting point,...

Apr1108 08:30 PM
Wizardsblade

7 
2,024 
Einstein's second postulate states that the speed of light is constant as viewed from any frame of reference. Most of...

Apr1108 07:23 PM
phyti

10 
1,836 
Suppose you are given the Lagrangian of a scalar field \Phi(t)
\mathcal{L} = \frac{1}{2} \dot{\Phi} \nabla \Phi ...

Apr1108 04:23 PM
samalkhaiat

9 
6,373 
I've seen several responses (and links) to the question "What happens when something is traveling at the speed of...

Apr1108 11:03 AM
pervect

20 
4,927 
Given the idea that a photon experiences only one 'timeslice' from its perspective, and exists as one elongated unit...

Apr1108 11:01 AM
pervect

7 
2,224 
Hi,
I have a computational question about the Hilbert action with an added GaussBonnet term. The Lagrangian L (...

Apr1008 09:49 AM
haushofer

5 
2,850 
I'm confused about how to understand the ct dimension.
I cannot get passed thinking that physically real...

Apr1008 12:45 AM
XVX

9 
2,547 
Hi all  this (seeming) paradox has been brought up on a few other forums with less than illuminating results. I'm...

Apr1008 12:02 AM
yuiop

13 
1,612 
I am trying to get through Special & General Relativity on my own. However I seem to reach a problem.
Imagine...

Apr908 11:56 PM
Tachyonie

14 
1,410 
I like to do whirlies with the kids down in my local park. I grab them by the feet and I spin them in a circle with...

Apr908 07:55 PM
michael879

24 
2,097 
Hey guys, to further my understanding of special relativity, could you help me out with this problem:
Two...

Apr908 04:16 PM
Antenna Guy

4 
2,054 
I have a few questions about these. My main question concerns the "theory" that all fundamental particles are...

Apr908 11:36 AM
michael879

1 
1,088 
The line element in a rotating plane, with angular velocity \omega is given,
in polar coordinates (t, r, \theta) by (...

Apr908 02:31 AM
Ich

10 
2,438 
I am trying to draw one of those nice plots of effective potential against radius , which suggest the position of...

Apr808 11:18 PM
Jorrie

111 
13,119 
"Violation of the equivalence principle for stressed bodies in asynchronous relativity"
...

Apr808 06:46 PM
pmb_phy

5 
1,267 
Hello,
First post. Thank you for letting me be a part of the discussion.
My question is, can the Law of...

Apr808 06:45 PM
superdirt

21 
7,868 
Ok so I begin by entertaining the following hypothesis:
Suppose a number of points are selected in spacetime, and...

Apr808 06:38 PM
pmb_phy

10 
1,747 
space is flat what the hell does this mean. It must be at least six foot thick as thats how tall I am? how thick is...

Apr808 06:11 PM
bockerse

5 
6,818 
For a free relativistic particle we have the condition
E^2\mathbf{p}^2c^2=m^2c^4.
putting p^0 = c^{1}E we may...

Apr808 02:41 PM
pellman

3 
3,875 
Two masses A and B are accelerated to a velocity V on close “parallel” paths.
They will experience gravity or...

Apr808 02:28 PM
JesseM

10 
1,721 
If I lift an object, does its mass increase due to my investing it with potential energy? If I then drop it, does its...

Apr808 11:24 AM
snoopies622

34 
4,364 
Does anyone know how to derive the wave equation in curved spacetime?
(g)^{1\over 2}\partial_\mu((g)^{1\over...

Apr708 11:01 PM
shoehorn

4 
3,690 
I'm still struggling with the concept of a mass of a photon. I understand that photons have momentum because of their...

Apr708 09:54 PM
pmb_phy

10 
2,045 
Can someone please have a look at my analysis here and tell me if there are any mistakes
the rest of the pistures are...

Apr708 08:48 PM
phyti

36 
2,919 
Electrical means are the only way to achieve high speeds of a particle. Is it possible that you reach a limiting speed...

Apr708 05:24 PM
clem

1 
878 
Does anyone know how to derive the quantum mechanical flux in curved spacetime?
e.g. flux = {1 \over...

Apr708 01:06 PM
Pacopag

0 
1,429 
I have a question about someone falling into a black hole. General relativity predicts that the reference frame of an...

Apr708 12:38 PM
michael879

6 
3,728 
An astronuat in a nuclear ship accelerates away from earth and gets very near the speed of light, .99999% in fact. ...

Apr708 11:27 AM
LURCH

9 
1,668 
according to the theory nothing is faster than light so if there were a rod very very long(eigth ligth min long) and...

Apr608 11:36 PM
korinteren

36 
3,416 
A small but possibly important correction:
Back in May 2006, pervect cited a page he found at the well known...

Apr608 11:09 PM
Johnsr86

9 
11,483 
Hey guys, what exactly is a 3 momentum? I can't any references to it anywhere on the net, which actually tells me what...

Apr608 05:06 PM
jtbell

8 
2,832 
Hello everyone,
I am new to this forum and would greatly appreciate your expertise in answering (or attempting to) a...

Apr608 02:58 PM
oliverswanshu

55 
6,573 
As an object that you have thrown is flying through the air, how can it know that it has kinetic energy? If you...

Apr608 11:14 AM
korinteren

22 
5,439 
lest say you have a man on the moon and one on mars. For them to be in the same frame of ref the only parameters that...

Apr608 06:43 AM
matheinste

8 
1,260 
Does the theorem still hold true, but triangle sides are curves?

Apr608 06:08 AM
Ulysees

14 
5,357 
How does nonlinearity of the gravitational field equations follow from the equivalence principle? I remember hearing a...

Apr608 05:47 AM
MeJennifer

1 
1,135 