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Feb2313 08:38 AM
ZapperZ

1 
30,369 
By looking at layman's books on physics I have picked up the idea that "virtual" particleantiparticle pairs...

Apr1012 09:20 AM
mfb

1 
535 
Brian Greene describe an experiment in his book "The fabric of the cosmos" pretending to illustrate the Bell test...

Apr1012 04:38 AM
Timbo

17 
3,093 
say you overlap two identical coherent light beams with a mirror but opposite phase so they effectively cancel each...

Apr912 09:11 PM
Vanadium 50

19 
1,482 
I have seen the ∂ symbol many times in wave function equations. What does it mean?

Apr912 05:10 PM
jtbell

1 
901 
I know even molecules can be used and the result still emerges. What is the density of of atoms or molecules when...

Apr912 04:23 PM
lostprophets

15 
2,158 
In regards to this article ...

Apr912 02:57 PM
StevieTNZ

0 
752 
I know, I know, it might be a little bit spamy to post another poll, but since the option 'Other' was gaining so much...

Apr912 10:40 AM
JamesOrland

29 
2,905 
Hello,
I am writing an appendix to my thesis where i try to explain how nmr works but i am having trouble...

Apr912 10:11 AM
simorgh

2 
921 
At classical harmonic oscillator, total energy is proportional to square of frequency, but at quantum harmonic...

Apr912 09:12 AM
exponent137

2 
990 
Hello!
On p.424 in the second edition of Altland & Simons, they compute an average as part of a renormalization...

Apr912 08:23 AM
Hypersphere

0 
613 
3 years ago when I lived in Jordan I met a Palestinian who believed that he had unified gravity with quantum...

Apr912 07:33 AM
Mark M

5 
1,136 
How many chemical shift measurements must be used to elucidate the structure of organic questions?????? I found this...

Apr912 03:09 AM
Chemist20

0 
653 
In nonrelativistic QM, we spend a lot of time examining bound statesenergy levels, spatial distributions, and all...

Apr812 10:19 PM
kof9595995

1 
772 
im currently writing a paper for one of my classes, and part of that paper requires me to "Discuss also the question...

Apr812 09:01 PM
Halcyonon

2 
1,061 
Is there fixed data for the threshold frequency of metals?
For example, is it possible to find out the threshold...

Apr812 06:17 PM
Olly_price

4 
6,368 
Hello,
I've been reading a book on QCD on I have a question: what is the purpose of the renormalization group? Is...

Apr812 05:07 PM
geoduck

3 
905 
Hi,
I'm doing a homework problem in my modern physics class and I'm stuck at a point. The question is "Show that...

Apr812 04:29 PM
Bob S

8 
1,943 
So if light acts like waves when interacting with huge objects and acts like regular particles when interacting with...

Apr812 01:51 PM
vanhees71

2 
794 
I am given the vibrational frequency of hydrogen, and I am asked to calculate the one for OH making certain...

Apr812 10:05 AM
Chemist20

0 
534 
Hi friends. I'm doing a homework problem about how degenerate orbitals split in the presence of a magnetic field. I...

Apr812 03:15 AM
M Quack

1 
620 
From the postulates of QM we know that any state ψ> is the same as exp(iθ)ψ>.
Ok so take the spin state of an...

Apr712 04:40 PM
mfb

5 
866 
let be N(x)= \sum_{n} H(xE_{n}) the eingenvalue 'staircase' function
and let be a system so V(x)=V(x) and ...

Apr712 04:39 PM
zetafunction

0 
608 
I can understand the whole mathematics in this effect. The thing that i could understand is the production of new...

Apr712 03:54 PM
darkxponent

3 
907 
Hey!
I have started reading about anyons in a book called fractional statistics and quantum theory.
In this book...

Apr712 01:25 PM
element4

13 
1,415 
I am reading a paper from Yakir Aharonov and others revisiting Hardy's paradox and I have a question. Let me state...

Apr712 12:35 PM
msumm21

1 
730 
Hi all. Just a quick question, probably a silly one.
Due to waveparticle duality all particles have both...

Apr712 10:44 AM
Einstein Mcfly

1 
700 
this has been asked by someone before, though, but, i think, never got answered
can the matter waves of, say, a...

Apr712 07:23 AM
mfb

1 
578 
in the various QM experiments:
after select event(s) have occured, we assume collapse of wave function and the...

Apr712 01:01 AM
StevieTNZ

3 
883 
I've been trying to read Bargmann's 1964 proof of Wigner's theorem, but I find it really hard to follow. This is the...

Apr612 11:37 PM
Fredrik

12 
2,151 
Hi all!
I've got a question concerning Wick's theorem. I followed the proof in the book by Fetter and Walecka and it...

Apr612 07:51 PM
MelvinSmith

0 
920 
Please I need help from anybody who knows how to use the DWBA program, DWUCK5. I'm finding it difficult to specify the...

Apr612 05:47 PM
Fizzle01

0 
756 
With regards to the photoelectric effect the wave theory does not match up to observations of instantaneous emission...

Apr612 05:02 PM
sophiecentaur

10 
1,351 
Hello,
I am studying the WignerEckart theorem and I have found some difficulties understanding the reduced matrix...

Apr612 02:28 PM
Tilde90

0 
921 
Hi
I am working my way through Griffith's Introduction To Quantum Mechanics and I have got to the section on...

Apr612 01:42 PM
Chopin

3 
941 
from my thinking nonlocality and entanglement are never a problem because in a totally determinstic universe, the...

Apr612 01:07 PM
billschnieder

395 
24,274 
Hello,
I am not educated in physics, but I would like to gain some understanding on the doubleslit experiment. I...

Apr512 04:19 PM
Drakkith

70 
6,658 
Hi,
I'm trying to calculate the thermal equilibrium expectation value of the displacement operator, i.e:
tr(\rho...

Apr512 01:28 PM
jilessmith

0 
890 
If ψ> is the state of a system of two indistinguishable particles, then we have an exchange operator P which switches...

Apr512 09:57 AM
Bill_K

3 
684 
I was just wondering that when we have a molecule, and you introduce heat, the molecule starts to get translation,...

Apr512 09:22 AM
DemoniWaari

4 
659 
If I give you a box, completely empty except for one hydrogen atom, could you theoretically measure the spin of its...

Apr512 08:58 AM
Naty1

5 
860 