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Feb2313 08:40 AM
ZapperZ

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42,253 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

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41,890 
Say we have dust filled universe. At some instant of time this universe has a mass density rho, and it evolves with...

Dec2109 08:20 PM
George Jones

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1,029 
Hey, I'm stuck on part of the calculation for the compton wavelength. Basically, my notes go:
Energy of Electron
...

Feb1410 03:53 PM
jtbell

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1,029 
Quick Question(s):
Who was it that tried to account for the EM force in terms of spatial curvature; i.e., who tried...

Apr2710 08:26 PM
Mentz114

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Lets say we emit a photon from the ground out towards the sky , and as the photon travels away from earth it gets...

Jul810 05:45 PM
cragar

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so, a bit of confusion here  suppose i have a spaceship that can acheive 0.99999C, and i decide to go to a star that...

Aug210 04:22 PM
Doc Al

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1,029 
Why doesn't a stationary charge experience a magnetic force? And why does a moving charge produce a magnetic field?...

Sep2113 02:54 AM
eightsquare

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Trying to understand black holes as much as possible without the difficult math....
I gather that matter  or...

May2708 04:26 AM
HarryWertM

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A thought experiment:
Say that you and I decide we are going to go into orbit around a black hole. I am brave and you...

Oct510 07:58 PM
PAllen

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1,028 
hi
if gravity is a force of attraction ,a natural question arises ,why it can't be repulsive?as there is a great...

Mar1911 07:55 PM
rchase

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1,028 
Hi all.
Suppose we have two objects A and B, and suppose we tie a rope R to the objects with the rope R's two edges...

Jun1911 09:30 PM
DaveC426913

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I like to try and derive little things by myself if I think it is manageable. One such thing is the addition of...

Dec1511 11:58 PM
nhmllr

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1,028 
What is E = \frac{m_{0}c^{2}}{1v^{2}/c^{2}}

Mar2112 06:54 AM
granpa

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1,028 
Dear Friends,
Discussion of the Einstein's Special Relativity clock paradox is often complicated by the role of...

Jul413 11:50 AM
ghwellsjr

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Okay, I realize that there are difficulties in combining the theory of GR and quantum mechanics, but I thought SR and...

Oct2906 04:41 PM
robphy

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1,027 
Why no FAQ for the Twin Paradox?
There are a few topics for which a FAQ would be very useful. I'd suggest that the...

Jun209 09:48 AM
DaleSpam

2 
1,027 
The Schwarzschild Solution to Einstein's Field Equations for gravity are said to be exact when outside a spherically...

Sep1309 04:02 PM
atyy

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1,027 
my question is. how did they get the time component of the 4momentum vector to be energy.
i try to derive it to...

Sep1509 08:07 AM
DaleSpam

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1,027 
When an object moves in curved spacetime, how does its angular momentum vector transform? My hunch is that the...

Oct1010 03:12 PM
pervect

2 
1,027 
hi everyone. i'm having trouble understanding the concept of proper time in general relativity.
suppose we have...

Feb714 06:04 PM
pervect

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1,027 
HI guys first post :cool:
I need to show that
B^2E^2/C^2 is invariant under Lorentz transformation (E and B...

Apr3004 09:31 AM
DW

6 
1,026 
A thought occurred to me when reading the Encarta article on relativity:
Now, it occurs to me that the velocity...

May404 08:44 PM
turin

8 
1,026 
Hey guys,
I have no background in physics but have been interested in time dilation for a while and have understood...

Aug1208 09:15 AM
armaan

2 
1,026 
According to the BiotSavart Law, the equation for the magnetic field around a charged particle moving with constant...

May509 08:51 PM
clem

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1,026 
I've always thought that understanding at a profound level requires real precision in the use of language. I was...

Jan1010 01:25 PM
LAncienne

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1,026 
In my cosmology lectures they say that a negative curvature gives an infinite space but I was thinking what about the...

Feb1910 07:06 AM
George Jones

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1,026 
The time dilation formula:
\Delta t'=\frac{\Delta t}{\sqrt{1\frac{v²}{c²}}}
says that the closer you come to the...

Jul1511 12:58 PM
Jaynte

3 
1,026 
Hi,
I just started reading "The Elegant Universe" as an introduction to physics. Up to this point I thought I...

Aug411 10:10 PM
DaveC426913

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Has any experiments been done equal to this scenerio where the twin leaving earth and seeing earth time dilated.. but...

Dec2912 11:02 AM
ghwellsjr

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1,026 
I like simple physical setups to articulate and generate good thought experiments.
Setup:
Consider a hole cut in a...

Mar1806 01:45 AM
my_wan

2 
1,025 
Does the theory of relativity include angular motion? Say we have one body synchronously orbiting a motionless body....

Sep508 06:41 AM
DrGreg

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1,025 
I have just recently began to understand relativity, right now I get time dilation and lenght contraction but I do not...

Jan409 11:02 AM
jtbell

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1,025 
My question is, which photon is the one that first hits the square in the following example
If I had a large...

Jan1110 07:35 PM
Zula110100100

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1,025 
Hey guys, i was just wondering what would happen if a person was on a spacecraft traveling at 0.9c was standing on a...

Mar1511 06:06 AM
nsh3a94

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1,025 
i constantly feel that newton was right in measuring the relative velocity.einstein makes use of light which has a...

Aug2211 02:32 AM
harrylin

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1,025 
While explaining how science works in my biology class my biology teacher said that relativity had been proved wrong,...

Dec1912 03:19 PM
PeterDonis

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1,025 
Hey ,if we need to calculate time dilation with an accelerating frame of reference,cant we simply use the lorentz...

Jan2607 11:56 AM
Chris Hillman

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If time stops at the speed of light, how does light travel throught space and time? Example: The light from a star...

Feb1110 05:06 AM
Matterwave

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1,024 
As long as there is any energy/mass at all in our universe, time will always be in a "slowed" state. So, let's say we...

Feb2611 03:42 AM
John232

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I am thinking about train paradox here. The only difference between the passenger and the person waiting at the...

May2111 11:38 PM
ZealScience

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http://arxiv.org/PS_cache/grqc/pdf/0310/0310002v3.pdf
Can someone explain the following statement on page 2 of...

Jan1312 08:12 AM
Naty1

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