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Feb2313 08:40 AM
ZapperZ

1 
37,500 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,234 
Random question that I thought of while trying to fall asleep last night. :)
We all know that galaxies moving very...

Jul1108 07:55 PM
Antenna Guy

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1,928 
According to my physics textbook, the equation E^2=\left(mc^2\right)^2+\left(pc\right)^2 suggests that a particle may...

Jul411 12:09 PM
Parlyne

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1,928 
In the current mainstream theory of black holes, there exists a singularity of infinite density. However, it seems to...

Jun2011 08:22 PM
bcrowell

2 
1,928 
How can the derivative of a basis vector at a point be the linear combination of tangent vectors at that point?
For...

Jul2711 04:30 PM
RedX

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1,928 
hi
how is space curvature around a mass. i mean what's its direction in real 3D space?

Dec904 11:02 PM
Majid

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1,927 
Consider a source of light S stationary in I and an observer R moviong with speed u . At the origin of time R is...

Nov1506 08:57 PM
bernhard.rothenstein

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1,927 
I've read about Schwarzschild and Kerr metric, I confused about the spacelike singularity(occur in nonrotating...

May2810 05:55 AM
stevebd1

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1,927 
Is this a possibility?

Sep311 05:03 PM
pervect

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1,927 
From a far away observer, thing falling into a BH takes infinite time to cross the horizon. At the same time, the...

Apr2511 12:07 PM
Naty1

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1,926 
: It that Real???
http://www.superstringtheory.com/forum/socboard/messages6/99.html

Dec303 03:29 PM
LURCH

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1,925 
If Eisenstein taught us the space time is one and the same thing, then how did he mathematicaly prove that. How did...

Jul2512 07:33 AM
PAllen

13 
1,925 
Consider the following "classical" example: ^{}_{}
A system Σ' moves away from a system Σ with relative velocity v...

Jul1512 07:35 PM
Muphrid

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1,925 
Please help with this. This is similar to the Einstein train experiment.
When C and C' are at the same place,...

Nov2013 07:58 PM
DaleSpam

48 
1,925 
Hi all
I was recently told that certain postulates of SR are equivalent or one can be derived from the other. Namely...

Oct607 05:48 AM
pmb_phy

7 
1,924 
I was reading this:
http://www.esa.int/SPECIALS/GSP/SEM0L6OVGJE_0.html
and apparently it seems that Martin...

Jan908 10:47 PM
jostpuur

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1,924 
In general, what can one say about the relationship between geodesic motion of (massive and massless) particles and...

Mar1710 08:04 PM
atyy

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1,924 
I did some searches, but couldn't find an answer to this on this forum.
Since a photon can travel 1 km, 1...

Jun513 07:09 PM
Vanadium 50

11 
1,924 
Hi,
I've just got the following question for you guys...
Say that Bob is travelling away from the Earth at...

Apr706 06:09 PM
Janus

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1,923 
In "Frozen Light" an article written by Lene Vestegaard Hau, it talks about Lene's experiments with, literally,...

Oct2406 10:44 AM
DaveC426913

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1,923 
It has been said one of the great mysteries of the universe is how light can be both a wave and a particle. Indeed...

Jan1608 11:22 AM
Magic Man

9 
1,923 
hey..while looking into the consequences of the invariance of light....we see that time needs to be slowed down in...

Jan2408 02:51 AM
Fredrik

10 
1,923 
Since everything in the universe is moving relative to the other, how can one measure an absolute velocity? Therefore,...

Feb708 08:07 PM
pervect

14 
1,923 
The earth moon distance = 3.8 * 10^8 meters
Time for light to reach moon = 1.266 sec.
A laser at the origin on earth...

Oct2908 10:18 AM
LURCH

2 
1,923 
Hi,all, problem:
2 stars, distance is 1 lightyear.
If I move one star, will the other star move 1 year later?
...

Mar310 05:08 AM
luxiaolei

2 
1,923 
Could the process of Electronpositron pair production work with anything else in our universe?
I.E. Could our...

Dec310 09:00 PM
stever19

0 
1,923 
I'm reading how the Lorentz equations allow for relativistic transformation that can include Maxwell's equations but...

Sep606 08:25 AM
RandallB

19 
1,922 
Is it possible that gravity and the strong force could be the same just on a smaller scale giving it different...

Nov908 10:00 AM
Jonathan Scott

3 
1,922 
I've been trying to put this together in my head for a while and it doesn't come out. For example, if there are more...

Dec1608 03:35 PM
Pippo

11 
1,922 
Because time slows down at the speed of light does then light itself potentially travel at almost infinity per zero...

Nov1612 09:44 AM
nitsuj

25 
1,922 
Pendulums tick faster when they weigh more. ie a falling pendulum in any gravity won't tick as it is effectively...

Jul1310 11:10 PM
gonegahgah

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1,921 
Let's say an observer A in his rest system has a wave function for an electron double slit experiment (psi function of...

Jul1311 12:32 AM
Mentz114

3 
1,921 
Hi, I'm reading this wikipedia article on the metric connection, and it says that the LeviCivita connection is a...

Oct2411 02:52 PM
UndeadCat

11 
1,920 
What sort of software do people here like to use to mangle, errr I mean manipulate, Tensors in General Relativity?

Aug2304 05:31 PM
pervect

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1,919 
In special relativity, the mass of an object increases as the speed approaches c. Geometrically, this can be...

Jun3010 05:53 PM
hawkingfan

6 
1,919 
Hi everyone,
I recently read an essay by Isaac Asimov called "Figure of the Farthest", which discussed the ideas on...

Sep2210 09:39 AM
jambaugh

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1,919 
Alright, I'm a bit ignorant when it comes to more advanced subjects (well, very ignorant...), but, from my...

Nov2810 09:10 AM
bcrowell

6 
1,919 
Hi guys, here's my question:
An accelerated observer (both in curved or noncurved space) who Fermi Walker...

Jul1611 02:22 PM
atyy

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1,919 
can a black hole accelerate an object to c(because its escape v is greater than c)

Dec3107 10:31 AM
cosmic.ash

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1,918 
In high school, doing modern physics, and was struck by a thought about light, energy of a photon and the "speed...

Oct1611 06:59 PM
yoron

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I don't know if this is the right place to post this but would a proton falling into a black hole experience tidal...

Jun2811 07:34 PM
bcrowell

10 
1,918 