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Feb2313 08:40 AM
ZapperZ

1 
41,667 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,316 
I have a question regarding the qualitative difference between General Relativity and classical newtonian gravity. I...

Nov213 05:35 PM
Herbascious J

4 
680 
Hi everyone, before I post I apologize for my bad English!
I am not a physicist but I am interested in this stuff...

Nov213 04:20 PM
Ibix

20 
1,680 
I know that there is an equation for an accelerating object that is already a notable fraction of the speed of light...

Nov213 12:01 AM
pixelpuffin

8 
903 
Lets pretend I am in a space ship and I am moving at the speed of light. There is a light bulb at the center of the...

Nov113 08:13 PM
Nugatory

5 
837 
Lets pretend I am in my space ship going in one direction at 0.9c. My brother is in his space ship going the opposite...

Nov113 07:10 PM
D H

3 
732 
What causes people to age differently?
Here is a simple example:
A man moves inertially between two clocks in...

Nov113 03:05 PM
ZapperZ

36 
2,099 
See the attached

Nov113 11:59 AM
WannabeNewton

14 
867 
has anyone conducted a successful experiment proving closed timelike curves via post selection and quantum entanglment.

Nov113 11:23 AM
PAllen

4 
772 
In the Galilean formula u=u'+v, the velocities are bold so we know they're vectors, so for instance if u'=(a,b), and...

Nov113 08:00 AM
clem

7 
1,129 
Please see the attached pic.

Oct3113 09:34 AM
nenyan

2 
440 
Starting with this equation,
E^2 = p^2c^2 + m^2c^4
With a photon, m = 0... what happens when E starts to get...

Oct3113 08:13 AM
tolove

8 
931 
Before people start bashing me for not reading up on other threads, I did try and perhaps I am not physicssavvy...

Oct3013 10:43 PM
DaleSpam

20 
1,681 
Hi everyone,
I've been reading posts here occasionally, and have been impressed with the amount and quality of...

Oct3013 09:56 AM
PeterDonis

22 
1,874 
Consider two parallel streams of electrons in vacuum. Each stream moves with constant velocity and carries a current....

Oct3013 03:33 AM
alpha358

4 
565 
Is There any impact/will there be any: of the concept of Einstein’s New Ether in science today?
I red that even...

Oct2913 10:50 PM
mfb

1 
580 
My question stems from a conversation I had recently with another physics buddy of mine and has to do with rotating...

Oct2913 05:28 PM
DaleSpam

14 
919 
Everyone knows that paradox. In true we can say who person is standing,so If we say that the person in earth is...

Oct2913 03:09 PM
Nugatory

2 
533 
Hi there, i have a lot of question about LorentzMinkowski geometry:
1) Is Lorentz metric degenere or...

Oct2913 11:28 AM
nomather1471

4 
606 
hi
is it possible to have null surface on spacelike hypersurface?
I have a null surface, I want to know if it is...

Oct2913 10:43 AM
sadegh4137

0 
481 
Hello! Consider the following problem: A space ship on a circular orbit at radius ##r## in a Schwarzschild metric...

Oct2913 10:42 AM
George Jones

12 
1,272 
The following is an outline of the theoretical basis of making a time machine with a traversable wormhole (if you...

Oct2913 08:35 AM
nomadreid

0 
422 
In a paper translated from the Russian, the author refers to "mm" and "nn" circles (including Minkowski circles) and...

Oct2913 05:48 AM
nomadreid

2 
525 
If we drop a charged particle and a neutral particle at the same time(same hight) in a uniform gravitaional field,...

Oct2913 05:17 AM
Bill_K

2 
548 
So for finding the magnitude of a vector, velocity for example, we use v=√(vx2+vy2+vz2), but in special relativity,...

Oct2813 10:27 PM
WannabeNewton

5 
634 
Can we show orthogonality of timelike and null vector?
http://u1310.hizliresim.com/1g/x/u0rkg.png

Oct2813 05:23 PM
nomather1471

7 
748 
I was thinking about one of the many resolutions of the socalled 'twin paradox' within SR framework. I realize many...

Oct2713 11:38 PM
adrian_m

13 
914 
Am I right in thinking that any bit of mass, eg. me, or my spoon, or a planet, can never not be moving? And also as...

Oct2713 05:31 PM
Simon Bridge

6 
619 
Hello all. When light goes through one medium to another, its velocity and wavelength change but frequency remains the...

Oct2713 02:44 PM
Nugso

13 
1,339 
Hello all,
In Carroll's there is a brief mention of how to get an idea about the curvature tensor using two...

Oct2713 01:47 PM
victorvmotti

3 
764 
This is a spin off from another thread:
First there are a couple of mathpages...

Oct2713 01:10 PM
yuiop

5 
750 
EDIT: Figured out question, don't worry guys.

Oct2713 10:01 AM
Nugatory

1 
425 
Let's tie a rope on an object, then we swing the object around in a circle, then we start running forwards while...

Oct2713 07:07 AM
DaleSpam

66 
12,045 
I keep getting the terms confused:
1) if I have the equation
Δr2+c2Δt2=s2
does one say that I am using the...

Oct2713 02:57 AM
nomadreid

3 
536 
Hello everyone,
One of the conclusions of relativity is that no massive object can move at v ≥ c, but with respect...

Oct2713 12:28 AM
ViolentCorpse

15 
2,455 
If an electron orbital the earth only influence by gravity,does it emit electromagnetic waves? if so, the radius will...

Oct2613 04:23 PM
WannabeNewton

5 
641 
I have red only about a few experiments conducted to detect the speed of light using interference pattern.
but i need...

Oct2613 01:01 PM
ghwellsjr

14 
856 
Hello,
First off, I'm not a physics student by any means, but it does intrigue me. I've been wondering about the...

Oct2413 11:02 PM
nitsuj

47 
11,452 
How does one change the dot product such that there is no dot product in between, just plain multiplication? For...

Oct2413 04:30 PM
Chestermiller

3 
465 
Given that molecules, atoms, protons, and neutrons are overwhelmingly space (i assume quarks and electrons are more...

Oct2413 11:48 AM
nitsuj

6 
795 
I have been reading an introductory book to General Relativity by H Hobson. I have been following it step by step and...

Oct2413 02:36 AM
Halaaku

9 
748 