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Feb2313 08:38 AM
ZapperZ

1 
36,443 
I have some questions regarding:
S = \sum_{n=0}^\infty\ S^n = \sum_{n=0}^\infty \frac{i^n}{n!} \idotsint \...

Aug1105 11:02 PM
robousy

0 
2,407 
In thinking about QM, I was wondering if anyone could comment on this? Back in prehistoric times, I did research using...

May811 08:19 AM
Fredrik

10 
2,407 
Why is it that we assume that the solutions to the timeindependent Schrodinger Equation are real? Why can't they be...

Sep1411 12:11 AM
tom.stoer

7 
2,407 
What are the limitations on the phase velocity of laser light? Is it true to say that the phase velocity of laser...

Jun308 02:37 PM
Andy Resnick

2 
2,406 
in Pages 307308 of Peskin and Schröeder we find
\delta S (< \Omega  T( \phi (x1) \phi(x2)..... \phi (xN) ...

Feb2511 10:10 AM
zahero_2007

2 
2,406 
Can anyone help me on this??
In a contest to drop a marble with mass 30 g from the roof of a building onto a small...

Mar1804 06:57 AM
jackle

3 
2,405 
Assuming that I have an atom that produces two photons having opposite polarization, and I send one toward the event...

Oct204 10:30 AM
humanino

19 
2,405 
excuse all the questions, but i've just recently started reading about quantum mechanics and want to know about what...

Jun2105 09:08 PM
straycat

9 
2,405 
Briefly, the 1D box problem goes like this:
A particle can move between x=0 and x=L.
The potential is:...

Jan1108 09:15 PM
JK423

6 
2,405 
Hi, I have a few question about orbitals
1. What does psi or wave function represents?
2. When talking about...

Jan109 07:33 PM
f24u7

3 
2,405 
When a photon is emitted, where did it come from? Did something cause it to be created and then emitted, or was it...

Apr1911 06:41 PM
Drakkith

10 
2,404 
Hi everyone
How do I show that the expression
\sum_{b'}\langle c'b'\rangle^{2}\langle b'a'\rangle^{2} =...

Aug208 07:55 AM
maverick280857

16 
2,404 
Hi folks, i've never taken a real quantum physics course, so this question miiight be really silly, but here it is:
...

Dec2410 08:04 AM
tom.stoer

7 
2,404 
How would be a good way of explaining Sationary Waves to somebody who does not know what they are? I'm talking...

Dec803 08:00 AM
slyboy

2 
2,403 
can i ask ..... how could planck's idea of quantised energy explain the ultraviolet catastrophe?
WHAT is being...

Jul1405 11:26 AM
reilly

5 
2,403 
In perturbation theory, how can I show that:
<\psi_n^{(0)}  H'  E_n^{(1)}  \psi_n^{(1)}> = <\psi_n^{(1)} ...

Apr1507 06:02 PM
Repetit

0 
2,403 
For a particular energy level in hydrogen, with quantum numbers n and l, one will find when considering the spinorbit...

Feb2110 04:26 PM
ytuab

6 
2,403 
Apologies if this has come up before, but a week or so ago I read a paper or article that said the photoelectric...

Jul606 06:31 AM
vanesch

9 
2,402 
Alain Aspect's experiment:
...

Nov1909 01:15 AM
Neo_Anderson

20 
2,402 
Sort of kidding with the title here. But seriously I am having trouble making progress in my study of QFT because I...

Apr1808 10:57 AM
reilly

11 
2,401 
How could sodium chloride produce chlorine (neutral atoms rather than ions) in a swimming pool?
I have always...

Jul1011 11:21 PM
SpectraCat

2 
2,401 
Beginners question: When electrons of all a certain kinetic energy (say 100keV) are decelerated are all the photons...

May305 08:05 PM
Meir Achuz

2 
2,400 
Hi all, since scattering amplitude is given as:
f(theta) = summation over l(from o to infinity)(2l+1)/k...

Sep3008 09:20 AM
malawi_glenn

1 
2,400 
I am pretty confused about how to construct states to make symmetric / antisymmetric combination so I would like to...

Mar210 07:34 AM
DrDu

3 
2,400 
Hi all, to begin this is my understanding of hawking radiation. A particle/antiparticle pair is generated. one...

Oct1813 02:28 AM
Demystifier

18 
2,400 
According to my book, uncertainty Q = 0 (where Q is an observable) is true when the state function is an...

Mar304 09:10 PM
turin

12 
2,399 
Hi does anyone know where i can find an online version of the quantum mechanical theory behind lasers and masers....

May1409 02:25 PM
f95toli

9 
2,399 
Both photons and electrons give the same kind of interference pattern in the doubleslit experiment, but while in the...

Dec513 10:13 AM
San K

39 
2,398 
Can someone explain how nonHermitian Hamiltonians are used to account for particle decay?

Feb2109 04:48 AM
per.sundqvist

5 
2,397 
Hello everyone,
I tried to describe my question but it seems getting too complicated and confusing to write down my...

Jun2310 01:59 AM
Physiana

5 
2,396 
I have to write a short essay answering this question (1st year university level). I am finding it very hard to get...

Jul3105 04:47 AM
ZapperZ

17 
2,395 
Can someone link me to a thorough online derivation of the EulerLagrange equation from the principle of least action?

Jun1807 09:41 PM
smallphi

1 
2,395 
funny little topic a friend and i were on. i think it does.

Jun2008 09:56 PM
pmb_phy

6 
2,394 
Hi!
I wonder if the Feynman rules in momentum space can also be applied to disconnected diagrams. So aussume I have...

Aug608 02:32 PM
Sunset

0 
2,394 
Hey there! I'm still a beginner with many physics theories, so this may be an obvious question. I understand that a...

Dec1412 05:42 PM
rkastner

12 
2,394 
say an ensemble consisting of N IDENTICAL bipartite systems. The system can be in either of the two situations.
A)...

Mar1708 10:05 PM
ouacc

2 
2,393 
We can calculate a de Broglie wavelength for a particle with momentum p. My question is does this apply to the lateral...

Jun1412 04:50 PM
Darwin123

9 
2,393 
As I understand the many worlds interpretation of QM, theres no collapse in the wavefunction just a splitting of the...

Jan2705 09:42 PM
vanesch

20 
2,392 
Dear friends,
I'm a 2nd year physics student and I've taken a subject called "Introduction to the structure of...

Feb2205 12:11 AM
Davorak

7 
2,392 
Is there a physical meaning to the electron "smear" or probability cloud? If an object (electron) was to somehow...

Feb609 08:40 AM
nuby

17 
2,391 