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Feb2313 08:40 AM
ZapperZ

1 
42,725 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,367 
I apologize for the the probably gross error on my behalf, but, not as a scientist in the GR /SR field, I am a bit...

Jun1308 05:53 PM
Nickelodeon

25 
2,543 
I understand the idea that, given two frames of reference, and measuring for a time T defined as the time between two...

Jun1208 07:26 PM
shinta

2 
1,911 
I'm reading the relativistic mechanics chapter, of Hestenes' New Foundations for Classical Mechanics.
After the...

Jun1208 05:21 PM
yuiop

11 
2,182 
Hallo
I was wondering if anyone could answer a question I had for some time.
I was thinking about the similarities...

Jun1208 05:17 PM
lbrits

1 
829 
Hello,
I am well and truly stumped on Doppler shift. The complete expression is
f'=f \gamma (1\beta...

Jun1208 02:01 PM
shalayka

7 
1,076 
what would be the difference between the idea of being at point A and moving toward B in spacetime; and being at...

Jun1208 01:16 PM
Fredrik

5 
1,515 
I was summarizing for myself the various fourvectors of mechanics:
\begin{align*}
x &= ct + \mathbf{x} \\
V &=...

Jun1208 08:19 AM
Peeter

9 
1,508 
Imagine the following scenario.
There is a long train moving at very fast speeds (approaching light speeds), one...

Jun1108 02:59 PM
Alex48674

2 
1,294 
Are vacuum solutions to the Einstein field equations always divergence free? How would one test this assumption?

Jun1108 01:44 PM
quasar_4

5 
1,349 
In the usual "windowless room" thought experiment it is stated that there is no experiment which can be performed...

Jun1108 12:21 PM
DrGreg

27 
2,754 
Suppose we have a box at rest that is filled with a uniform gas. We denote the volume by V and the pressure by p....

Jun1108 12:04 PM
Mentz114

1 
938 
Hi folks  I'm struggling here! Please help ;)
Surely the concept of relativity of simultaneity is an illusion...

Jun1108 10:32 AM
ehj

32 
2,959 
1. Let S' be an x'y'coordinate system. Let the x'axis of S' coincide with the xaxis of an xycoordinate system S....

Jun1108 08:53 AM
arbol

4 
1,295 
What physical meaning can be ascribed to the nondivergence of the Einstein tensor? I find it counterintuitive since...

Jun1108 06:53 AM
snoopies622

3 
1,013 
Ok, I know this topic has been discussed before..
I just recently found out that we can see the light from a star...

Jun1108 06:12 AM
tinytim

4 
9,374 
Can an electromagnetic wave have a phase velocity greater than c? Is the phase velocity of a photon always c?
As...

Jun1008 06:49 PM
yuiop

4 
7,979 
I'm reading Wheeler's spacetime physics and have been doing some newbie SR problems.
I thought up what shouldd be an...

Jun908 09:31 PM
adimare

4 
1,461 
I propose a new look at lenghts and times relative to S' and S (at least new to me).
Let S' be an x'coordinate...

Jun908 09:43 AM
Ich

3 
1,309 
Im just an amateur, and I read that Newton's Equation F=ma doesnt work when approaching light speeds because of a...

Jun708 05:13 PM
aelbaruk

56 
7,263 
Let S' be an x'y'coordinate system. Let the x'axis of S' coincide with the xaxis of an xycoordinate system S, and...

Jun708 04:23 PM
birulami

8 
2,486 
Hi all.
I don't understand how charged particles can travel faster than the speed of light in that substance.
I know...

Jun708 03:52 PM
tinytim

10 
1,639 
I can't find anything on the net, but it seems to me that Einstein would have had to "guess" the time dilation into...

Jun708 12:55 PM
DaleSpam

11 
4,411 
Consider a disc in the framework of special relativity. It's initially at rest in an inertial frame, and then you get...

Jun708 11:55 AM
DaleSpam

1 
1,567 
Take a look at this following paragraph that i wrote in another thread
"think of two rockets moving at each other...

Jun708 11:27 AM
Janus

3 
1,361 
I'm going to state that two inertial bodies that close distance on each other will (becouse of loss of...

Jun608 11:47 PM
Janus

8 
2,161 
Do I need to know calculus? Or do I need to know differential equations? Do both of the theories even use the same...

Jun608 06:37 PM
lbrits

3 
2,988 
I'm having trouble understanding the simultaneity experiment with Alice on the railroad car, and Bob observing from...

Jun608 03:44 PM
neh4pres

58 
5,722 
Consider a train traveling at a relativistic velocity, with three observers. One inside the train, and two outside the...

Jun608 02:55 PM
tinytim

7 
1,853 
can anyone give me the webpage link of this paper by Einstein
Einstein, Albert, 1911, "On the Influence of Gravity...

Jun608 08:55 AM
hedenqvist

5 
4,637 
We all know how the metric of GR is a generalization of the flat Minkowski spacetime metric. But I wonder if the SR...

Jun608 08:16 AM
Ich

2 
1,001 
In GR, gravity is seen as property of the geometry of spacetime (curvature) as opposed to a force field. Does this...

Jun508 08:10 PM
MeJennifer

5 
2,579 
I am selfstudying GR and have run into a problem. In Sean Carroll's book 'Spacetime and Geometry', he states what...

Jun508 08:02 PM
bdm000

3 
2,519 
http://www.youtube.com/watch?v=3AunBigvoY
i would love to witness something like this, i still dont quite...

Jun508 04:37 PM
granpa

1 
1,018 
I am just a little bit unsure about something I read on the "twin paradox".
It talks about Dick and Jane who are...

Jun508 02:32 PM
yuiop

7 
4,236 
what is to top speed that this rocket can achieve as seen by a stationary observer? Also if you look at the...

Jun508 01:10 PM
neh4pres

22 
2,140 
I'm posting this to confess that I have never understood how the universe can be expanding on large scales and at the...

Jun508 09:34 AM
Ich

45 
5,416 
Please let me know if length contraction could be derived without using synchronized clocks.
Thanks in advance.

Jun508 06:29 AM
DrGreg

34 
4,074 
We all know this book... its is basically the SR as we know it.
you can find it here...

Jun508 06:15 AM
Histspec

16 
3,054 
http://camoo.freeshell.org/30.5quest.pdf
Latex source below, please click on link above, though.
I've been...

Jun408 10:35 PM
lark

4 
1,690 
The kinetic energy of an object can be shown to be:
Ekin = m*c^2  m0*c^2
Where m is the relativistic mass, m0 is...

Jun408 08:33 PM
Antenna Guy

24 
10,874 