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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
35,521 
Hey all. So, I understand that every bound electronic state will have zero average electronic momentum, because...

Aug1010 03:25 PM
ani4physics

8 
1,243 
Of course every prove of this type have some mistake.
If nobody will see I will post solution!
\hat{A}, \hat{B}...

Aug1010 03:23 AM
Petr Mugver

28 
3,119 
Got an idea for something that I think with the abundance of bright minds here I will find the oversight that makes...

Aug1010 01:37 AM
AshsZ

4 
975 
I have looked at several derivations of the Schrodinger equation but the one I like the best is from Piravonu Mathews...

Aug910 12:57 AM
Nemanja989

6 
3,227 
Is position not an observable of a photon?

Aug810 07:38 PM
Fwiffo

37 
4,860 
why is there an upper limit to the photon energy that can be observed in the emission spectrum of the hydrogen atom?

Aug810 06:59 PM
Eudoxie

2 
3,200 
In proving the Ehrenfest Theorem
This is the typical first line:
\frac{d }{dt}<O> = \frac{\partial}{\partial t}...

Aug810 06:52 PM
facenian

1 
1,181 
Hi all. I have been thinking about this problem for quite a while now. Still kinda clueless. We know that when we...

Aug810 10:17 AM
ani4physics

9 
1,486 
Hello, I would like to ask if there is a standard explanation of decoherence in the universe as a whole.
I can see...

Aug810 08:18 AM
RUTA

29 
2,414 
I got some good responses to my last thread on here I thought I'd try one more.
I'm wondering about the multiverse...

Aug710 07:37 PM
Xtensity

2 
1,897 
This is taken from a text problem, but I am putting it in this section because I think my question goes beyond the...

Aug710 03:00 PM
Petr Mugver

4 
1,439 
Every resource I can find that discusses the AharonovBohm effect states that the phase shift in SI units is given by...

Aug610 07:40 PM
ballzac

7 
910 
Can two objects overlap in spacetime? Why or Why not? If so, what circumstances must exist? If not, by what mechanism...

Aug610 05:10 PM
stevmg

5 
2,537 
I know if energy just suddenly appears in a vacuum it will become radiation in some random form of...

Aug610 03:31 PM
quark

2 
1,174 
I lack the fundamental aspect of quantum entanglement and I am trying to fully understand it. The problem I have is...

Aug610 02:58 PM
adriank

8 
1,275 
Say you want to evaluate this integral:
\int^{\infty}_{\infty} \frac{dx}{x^2A}
Since the bottom factors into...

Aug510 10:42 PM
RedX

5 
1,552 
My question is about which properties a particle can be said to possess. I understand that in accordance with...

Aug510 01:09 PM
eloheim

18 
2,799 
Virtual particles confuse me a bit, because although the ones which exist for such short times in Feynman diagrams...

Aug510 11:59 AM
kexue

1 
1,206 
Dear all,
I was wondering if the following formula is correct or not:
= \otimes
where A, B, C, D are...

Aug410 10:02 PM
ismaili

0 
637 
Hi, I have a question which I've been pondering over and would like to have an anwser to. I'm not schooled in physics...

Aug410 08:07 PM
unusualname

1 
1,103 
This may be more of a maths question, but because I may actually just be interpreting the expression wrong, I think...

Aug410 06:26 PM
NanakiXIII

2 
999 
Can anybody help me out with equation 9.25 in Srednicki's QFT book?
He says the in the eq. 9.25 an integration by...

Aug410 04:40 PM
kexue

3 
1,159 
Hi,
I am not a physicist. I am trying to understand something about the behaviour of materials for computer...

Aug410 12:07 PM
The_Duck

1 
1,380 
I understand that if you move a charged particle, you can create a photon, the basic unit of electromagnetic energy.
...

Aug410 10:58 AM
dcwarrior

0 
1,189 
I am hoping it may be helpful to separate Bell's logic from Bell's mathematics ...

Aug310 08:47 AM
DrChinese

215 
21,462 
According to quantum physics energy only exists in small pockets of energy called quantumor something like that,I...

Aug310 08:42 AM
tom.stoer

51 
9,020 
If the cells in our body (including brain cells) are replaced every 7 years, then in a sense we should be completely...

Aug310 12:19 AM
Lok

7 
1,255 
This relates to Doppler's effect.
The phenomenon: It is quite simple and says that light emitted from a moving...

Aug210 02:28 PM
tom.stoer

3 
1,915 
Can someone tell me what mass is other than particles with mass react to a gravitational field?
Electrons and photons...

Aug210 05:22 AM
kexue

10 
1,440 
Im reading in a quatum mechanics book and need help to show the following relationship, (please show all the steps):
...

Aug110 07:51 PM
ismaili

2 
2,151 
Any measurement device used to witness the phenomenom seems like it would disrupt quantum entanglement. How do...

Aug110 07:40 AM
DevilsAvocado

2 
2,846 
Does the basic geometry of packing differ with more fundamental particles?

Aug110 01:00 AM
Loren Booda

0 
742 
Hey folks, I'm trying to understand a couple of calculations in ChernSimons theory and I'm stuck.
I want to prove...

Jul3110 11:14 PM
weejee

1 
1,180 
I am confused as to how the mass equivalence of the the 3 gluons in at nucleon can give rise to an increase in the...

Jul3110 03:22 PM
cbd1

19 
2,453 
I know It is not EM wave.
It is not probablity wave since probablity can never be negative.
But I think De...

Jul3110 10:42 AM
munaizag

7 
5,237 
position,velocity cannot be found simultaneously with appreciable accuracy,why is it so?

Jul3110 08:00 AM
adaptation

6 
1,276 
To begin, I am an avid physics enthusiast and after reading countless books, there are a few questions that pester me...

Jul3110 12:22 AM
J.W. Coleman

3 
828 
Hello everyone,
I recently found this forum and have a question about spooky entanglement. When I first heard of...

Jul3010 08:56 PM
QuarkCharmer

1 
716 
Hi,
for my exam i"m rereading Peskin&Schroeder and stumbled across equations 2.212.25 where the canonical...

Jul3010 08:06 PM
ismaili

19 
2,440 
Acc. to QM no two particles can be in the same state at the same position at the same time, but how does that...

Jul3010 07:48 PM
Fwiffo

51 
4,445 