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Feb2313 08:40 AM
ZapperZ

1 
37,377 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,138 
Question 1: How does the metric relate to the light cone at a particular point? Obviously, the metric should determine...

Oct1712 12:37 AM
pervect

17 
1,334 
This is a question which has been intriguing me, if two photons A and B travel in opposite direction, what would be...

Oct1612 10:14 AM
harrylin

39 
4,967 
1. Is there anyway we can measure time without depending on or using light? If we can, what are they and do special...

Oct1612 10:04 AM
Erland

99 
5,253 
if possible could you tag some good video lectures may be feymann or any other good source..thanks...!!

Oct1612 04:28 AM
shivaniits

35 
3,470 
Hi. I did a quick search for threads on the block universe and came across one about the implications of the block...

Oct1512 06:19 PM
Vanadium 50

8 
1,144 
Does time dilation only affect matter that has mass?
For example, A spaceship is 1 light year away from Earth at...

Oct1512 04:21 PM
Milfeulle

3 
696 
Hi,
The theory of special relativity is based on assumption that the speed of light in vacuum does not depend on...

Oct1512 03:16 PM
bgq

7 
797 
Is it possible to diagonalize the Kerr metric in the BoyerLindquist coordinates? If so then I think calculations with...

Oct1512 02:43 PM
bcrowell

5 
2,300 
hello,
please see the attached snapshot (taken from 'Problem book in relativity and gravitation'). In the last...

Oct1512 01:32 PM
zn5252

8 
839 
Hello, first time poster here!
I am trying to understand some results I am getting from this "Relativistic Star...

Oct1412 04:48 PM
danielgoodman

2 
845 
Good day!
I am quite blur with the Spacetime concept proposed by Einstein.
Can anyone explain briefly on what he...

Oct1412 04:34 PM
Naty1

10 
1,094 
Hi All,
I am still trying to wrap my head around the five light year stick and the idea that if you push an object,...

Oct1412 01:42 PM
lightarrow

13 
1,456 
If we set c=G=1, then c=1 leads to L=1/T , the G=1 means that M=L^3/T^2 and combining the two means that M=L=1/T so...

Oct1412 12:35 PM
stevendaryl

6 
865 
I was told in another thread that saying that the Galilean relativity of Newtonian and classical mechanics could be...

Oct1412 07:19 AM
D H

39 
3,182 
While I was looking up E=mc^{2}, I have learned such formula only applies to stationary objects and for kinetic...

Oct1312 07:26 PM
bcrowell

1 
750 
I would like to know if there are exact solutions using General Relativity to determine: 1) time dilation from...

Oct1312 06:24 PM
tom.stoer

9 
1,016 
I know little to nothing about G.R. but it is interesting to look up knowledge,especially physics, so please correct...

Oct1312 01:18 PM
Naty1

4 
877 
I have a small intuitive issue with the idea.
If you could humour me for a moment, imagine a particle moving at...

Oct1312 07:36 AM
JustinRyan

5 
793 
Kerr–Newman metric:
c^{2} d\tau^{2} =  \left(\frac{dr^2}{\Delta} + d\theta^2 \right) \rho^2 + (c \; dt  \alpha...

Oct1212 06:41 PM
Mentz114

2 
965 
Hello all...
I am by no means a physicist and neither are my colleagues, however at time we find ourselves...

Oct1212 02:49 PM
nitsuj

11 
1,029 
Hello, I've just registered to ask this question. This is something that's been bothering me for some time. I have a...

Oct1212 01:21 AM
robphy

12 
1,327 
One thing that puzzles me is that, we are looking for the elusive graviton as a medium for transferring gravity. But...

Oct1112 06:49 PM
genphis

7 
844 
In another thread, Bill_K writes:
Wald, is one of the sources that does it the "wrong" way. But it seems that...

Oct1112 05:34 PM
Mentz114

31 
1,716 
Intro:
If one was to measure the redshifts and distances of all galaxies around earth, they would come to a...

Oct1112 03:24 PM
tom.stoer

4 
1,003 
Hi,
I was reading "Why does E=mc2 and why should we care". This is a statement from the book:
"There is a good...

Oct1112 11:57 AM
Sunfire

8 
1,168 
Ok I am wondering what would happen if an antiblack hole collided with a black hole of the same mass. Would they...

Oct1112 01:21 AM
temporalshift

8 
1,233 
In the Equation
E=hλ
Could the variables be subsituted for other similar energy problems like
E=mc2?
Would then...

Oct1012 08:20 PM
dbmorpher

3 
820 
hello..
I am reading "Relativity, the Special and The General theory of relativity by A. Einstein", and i have a...

Oct1012 03:38 PM
harrylin

3 
868 
I understand that in order for a space to be conformally flat that the vanishing of the Weyl tensor is a necessary...

Oct1012 12:47 PM
Bill_K

1 
566 
Einstein in his "Relativity: The Special and General Theory" ch.VIII explains that simultaneity between events placed...

Oct1012 10:34 AM
harrylin

47 
2,786 
Meaning of ct in Lorentz transformation 
In Lorentz transformation matrix, the first column is defined as  ct, not...

Oct1012 09:45 AM
simoncks

5 
754 
From what I've read, particle accelerators accelerate particles to near the speed of light. As the speed of an object...

Oct1012 05:14 AM
mfb

15 
1,627 
Hello everyone,
I've been reading the excelent review from Eric Poisson found here.
While reading I found a...

Oct1012 05:01 AM
PLuz

0 
500 
I understand that we can write the 4force in terms of the vector force based on velocity, and the energy of the...

Oct1012 12:37 AM
Muphrid

5 
725 
I'm listening to Prof. Leonard Susskind's lectures on GR on youtube.com at...

Oct912 02:33 PM
pervect

9 
1,532 
I am aware of the motives of finding a modification of Newtonian mechanics, but the effects of relativity are so...

Oct912 11:41 AM
Histspec

18 
1,996 
I am confused about one of the basic findings of relativity, that all coordinate systems are equal and there is no...

Oct912 05:57 AM
Jeronimus

5 
704 
Hi all, I'm in a modern physics course and am surprised by how confused I am about special relativity. I know...

Oct912 01:17 AM
ghwellsjr

10 
1,144 
After an analogy with air and water waves, which are limited in speed by the density of the medium in which they...

Oct912 12:21 AM
Serge58

3 
512 
Hi,
I am new to this forum, and I wish I get some help here.
I really can't find any solution to this paradox; I...

Oct812 10:16 PM
DaleSpam

99 
7,238 