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Feb2313 08:38 AM
ZapperZ

1 
30,409 
So, the three very small quantities:
Planck length
Planck mass
Planck time
Does the physical interpretation...

Jan2514 10:37 PM
Tclack

4 
279 
Suppose that I have an atom in one corner of a room, and I fire a photon toward the opposite corner (and assume that...

Jan2514 07:05 PM
mfb

1 
241 
Hello.
I'm now working in the spectroscopy and I'm wondering in one instantaneous moment of ionization.
Let's...

Jan2514 05:37 PM
goodphy

5 
347 
Is the rather continuous spectrum of the Sun due to redshift/blueshift of the radiation emenating from the Sun? I...

Jan2514 04:20 PM
edguy99

5 
324 
For those who read carefully the paper by Esther Hänggi and Stephanie Wehner: "A violation of the uncertainty...

Jan2514 12:58 PM
Suwailem

4 
359 
Does superposition have a radius or a space covered distance which cuts off at a certian point based on the size or...

Jan2414 10:04 PM
StevieTNZ

12 
441 
I understand that Feynman diagrams can be expressed either in the position or momentum representation.
Is the...

Jan2414 07:52 PM
Chopin

1 
315 
I keep hearing people say, "comparing particle spin to a spinning top will lead you in the wrong direction." I'm...

Jan2414 02:16 PM
vanhees71

25 
868 
In a recent paper Steve Hawking is reexamines black holes.

Jan2414 02:10 PM
ZapperZ

1 
331 
Consider the potential below:
V(x)=\left\{ \begin{array}{cc} \frac{e^2}{4\pi\varepsilon_0 x} &x>0 \\ \infty &x\leq...

Jan2414 04:26 AM
Hawkwind

1 
285 
First I want to admit that I'm not a physicist, but I'm very interested in physics. I have some questions about...

Jan2414 01:47 AM
bhobba

5 
280 
Hi,
The violation of Bell's inequality says that quantum mechanics can't be both local and realistic. Let's assume...

Jan2314 04:01 PM
greypilgrim

8 
390 
In quantum field theory pairs of virtual particles can appear from vacuum and quickly annihilate each other, for...

Jan2314 09:03 AM
Hawkwind

8 
397 
http://i41.tinypic.com/2z4gy9u.png
I'm not sure how they got equation 4.5
Starting from ##\psi'> = U_{(\vec{a})}...

Jan2314 02:27 AM
unscientific

8 
297 
Hi,
I'm not a scientist, but a documentary filmmaker doing research on the nature of reality. An essential...

Jan2214 08:38 PM
berkeman

27 
1,361 
I mean many people try to abstract the classical world but isnt it just the accumulation of QM properties that build...

Jan2214 08:07 PM
bhobba

6 
392 
Hi guys, I'm not sure how to evaluate this inner product at step (3.8)
I know that:
##\hat {H} \phi> = E...

Jan2214 07:04 PM
unscientific

13 
355 
Hi,
I've tried several times to get my head around this, but every way I look at it Hawking Radiation doesn't seem...

Jan2214 04:48 PM
Stonius

12 
947 
Every general explanation of the quantum zeno effect I've found is (from my perspective) so full of gaps that I cannot...

Jan2214 01:36 AM
wle

3 
414 
Hi, I'm trying to get my head around Schrödinger's equation and quantum wave theory. I'll try to shortly state how I...

Jan2114 09:49 PM
The_Duck

3 
228 
Here is an ultra short repeat of the Zeno Paradox, but please google it for a longer version with pictures etc:
...

Jan2114 06:04 PM
bhobba

2 
302 
Hey guys, Ive been trying to find out an answer to this question I had today but couldn't find it. The question is...

Jan2114 05:56 PM
bhobba

4 
292 
In Principles of QM by Dirac, 4th Ed page102 he gives the following:
Limδx→0(Deiγ1)/δx = Limδx→0(D1+iγ)/δx...

Jan2114 05:43 PM
bhobba

17 
582 
According to phys.org:This is very unclear to me.
How would one coarsen a reference angle? It seems to me it would...

Jan2114 01:39 PM
.Scott

4 
269 
http://i41.tinypic.com/or6ja8.png
Shouldn't the integrating factor be ##exp(\frac{m\omega x}{\hbar})##?...

Jan2114 08:10 AM
vanhees71

2 
250 
A very handwaving argument for weak localization is the following:
In a conductor the electron can take many paths...

Jan2114 12:33 AM
Jilang

5 
267 
Hello all!
On the problem of taking elements of different (degenerated)state vectors that do not vanish on the...

Jan2014 03:53 PM
vanhees71

1 
266 
This equation (see attachment) appears in one of Prof. Susskinds's lectures on Quantum Mechanics: in trying to...

Jan2014 02:04 PM
Maximise24

6 
302 
In the theory of degenerate perturbation in Sakurai’s textbook, Modern Quantum Mechanics Chapter 5, the perturbed...

Jan2014 01:42 PM
Avodyne

9 
618 
So, a true vacuum is a vacuum devoid of space/time and any form of particles, correct? Is it correct that a true...

Jan2014 01:11 PM
Jilang

12 
725 
Hey guys,
I’m interested in knowing if there are any known implications of quantum theory in the macroscopic scale,...

Jan2014 08:15 AM
DevilsAvocado

27 
1,342 
The classical physics developed by people such as Fraunhoffer and Fresnel seems to work very well
at predicting the...

Jan2014 01:05 AM
San K

10 
680 
Regarding a potential well that is proportional to 1/x, are the amount of possible energy levels finite or...

Jan2014 12:11 AM
tom.stoer

4 
307 
Noone is suggesting that this is exactly the same as the waveparticle duality that exists at the quantum scale (e.g....

Jan1914 08:06 PM
bohm2

78 
16,278 
Hello,
I am thinking for some hours about the commutation of the fieldOperator/(annihilationOperator): \Psi and...

Jan1814 11:30 PM
Avodyne

3 
346 
Well I am trying to understand the adjoint representation of the su(2) algebra.
We know that the algebra is given:
...

Jan1814 05:03 PM
dextercioby

1 
285 
Hello everyone!
I'm a little confused. The FermiDirac distribution is about every electron in a metal or only about...

Jan1814 11:16 AM
ilconformista

8 
265 
Electromagnetic waves are two fields, an electric field and a magnetic field, they are at 90 degrees to each other. So...

Jan1814 09:24 AM
andy+food=joy

0 
253 
I know this has been asked before but Im still not getting it. Does anyone know why a classical deterministic world...

Jan1814 07:14 AM
tom.stoer

26 
1,204 
I've come across countless sources that gauge fix SU(N) YangMills fields using the typical U(1) gauges (e.g. Lorenz...

Jan1814 02:19 AM
tom.stoer

29 
1,185 