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Feb2313 08:40 AM
ZapperZ

1 
41,556 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,199 
Has anyone ever analysed Einstein's equations in 1+1 spactime dimensions?
It seems to me like this would provide a...

Apr1608 09:46 AM
coalquay404

2 
2,025 
The obvious objection to the famous thought experiment with one of a twins moving away from the earth is, couldn't you...

Apr1508 12:02 PM
Mentz114

15 
2,418 
A long time ago, Galileo stated the vertical motion of a falling body is not influenced by its horizontal motion. Is...

Apr1508 10:30 AM
Jorrie

71 
11,774 
I guess this is my last theme here with this nick and from this IP:) But I just love the answer that came to my mind...

Apr1508 09:23 AM
neopolitan

1 
1,955 
I am not a physics expert but have been having a discussion about the effects of the Special Theory of Relativity with...

Apr1508 07:45 AM
jtbell

21 
2,470 
So after hearing a few theories, I had this idea that seems to make some sense. The problem is that all of the math...

Apr1408 07:09 PM
RandallB

1 
1,160 
I understand that the speed of light in a vacuum is supposed to be constant. However, I am having a problem...

Apr1408 04:46 PM
paw

14 
2,295 
While reading about the de Sitter universe I usually see the following relation between the curvature scalar and the...

Apr1408 12:42 PM
Magister

0 
1,276 
I am sure this question in some form gets posted here all the time again and again, but I somehow can not find it in...

Apr1408 09:41 AM
jviksne

7 
1,307 
Last night I watch a show about the birth of our sun on the Science channel. At one point they talked about how it...

Apr1308 10:33 PM
Helios

5 
3,246 
I am not a physics major but have always been perplexed by the apparent paradox of two issues:
1. If we use the...

Apr1308 06:11 PM
Mentz114

4 
941 
Figure 24 in "Spacetime Physics" by Taylor & Wheeler
The figure illustrates the effects of free float on the...

Apr1308 04:16 PM
Daverz

5 
1,617 
Im trying to describe a system of two kerr black holes and I was wondering if this was even possible? Im currently...

Apr1208 07:33 PM
xantox

5 
1,419 
I'm doing a research project for a class in advanced differential geometry, and have chosen to cover dynamical...

Apr1208 05:51 PM
geoffc

7 
3,016 
like my previous post on two body black hole solutions, Ive got a question about a nonstationary black hole which is...

Apr1208 05:47 PM
michael879

2 
1,191 
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 
1,948 
I've read Schwarzschild paper and I don't understand his conditions
"The solution is spatially symmetric with...

Apr1208 11:47 AM
tinytim

2 
2,145 
Can anyone tell me where can I get detailed derivation of PlanckEinstein Transformation of temperature in the...

Apr1208 09:11 AM
Frank Lampard

0 
1,703 
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 
1,985 
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 
2,026 
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 
1,855 
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 
6,439 
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 
4,945 
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 
2,299 
Hi,
I have a computational question about the Hilbert action with an added GaussBonnet term. The Lagrangian L (...

Apr1008 09:49 AM
haushofer

5 
2,855 
I'm confused about how to understand the ct dimension.
I cannot get passed thinking that physically real...

Apr1008 12:45 AM
XVX

9 
2,556 
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 
1,615 
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 
1,411 
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 
2,103 
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 
2,110 
I have a few questions about these. My main question concerns the "theory" that all fundamental particles are...

Apr908 11:36 AM
michael879

1 
1,095 
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 
2,442 
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 
13,167 
"Violation of the equivalence principle for stressed bodies in asynchronous relativity"
...

Apr808 06:46 PM
pmb_phy

5 
1,268 
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 
7,883 
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 
1,750 
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 
6,835 
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 
3,891 
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 
1,725 
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 
4,384 