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Feb2313 08:38 AM
ZapperZ

1 
35,347 
When the Z boson is around can a neutrino interact with a particle other than an electron? And how does the neutrino...

T 06:07 PM
Rob Hoff

0 
1 
what did feynman mean when he said "positrons are electrons travelling backward in time"?

T 04:31 PM
PeterDonis

10 
231 
In chapter 2.2 of Feynman's book on QFT, he states that the probability amplitude of a particle going from a to b is...

T 03:51 PM
atyy

4 
127 
When drawing conclusions from this most important and profound theorem, I wonder if somebody has interpreted its proof...

T 02:24 PM
gill1109

76 
5,609 
This quantum vacuum thing... i'm thinking about these virtual particles popping in and out of existence. Does that...

T 02:05 PM
Avodyne

6 
254 
I'm not 100% sure that this is the right forum to post this, but I think that the people who read the Quantum Physics...

T 11:14 AM
gill1109

103 
2,491 
I am curious what a photon looks like if we could observe it pass through space. It's also supposed to be oscillation...

T 10:06 AM
bhobba

13 
285 
Forgive me if this is a dumb question; from what I've been reading an electron can exist simultaneously in two places....

T 06:21 AM
Drakkith

20 
792 
I want to discuss the theorem proved in the article "Quantum states and generalized observables: a simple proof of...

T 06:00 AM
micromass

31 
3,130 
hey
I got a questions and appreciate obv any reply. Im regarding to Capitel 12, page 128ff. from Gustafson, Sigal;...

T 04:47 AM
pat1enc3_17

3 
284 
Hello everyone, this has been on my mind for a while and I finally realized I could just ask on here for some input :)...

Y 03:51 PM
dextercioby

5 
295 
hi there...
what is a point in a space?
classical math tells us that a point is:
 an exact location on a...

Y 12:24 AM
bhobba

47 
1,527 
As the only thread I've ever started before (http://www.physicsforums.com/showthread.php?t=369328 ) attracted a lot of...

Jul2714 01:53 PM
akhmeteli

77 
7,274 
if we have two noninteracting particles of mass M in a onedimensional harmonic oscillator potential of frequency ω,...

Jul2714 01:04 PM
Jilang

27 
642 
The definition I have for a 2point correlator is $$\langle \phi_1(x_1)\phi_2(x_2)\rangle = \frac{1}{Z} \int \mathcal...

Jul2714 12:58 AM
MathematicalPhysicist

24 
1,099 
I can tell this is simple, but I'm just not seeing it: (pages 146147)
Radial equation = d^{2}u/dp^{2} = _{0}/p +...

Jul2614 09:32 PM
strangerep

4 
317 
I am new here and was wondering what Schrodinger's Cat is and why it matters.

Jul2614 09:15 PM
Nugatory

1 
302 
I had a course of computational physics in university. When the professor wanted to nondimensiolize the Schrodinger...

Jul2614 03:36 PM
Jazzdude

3 
338 
Hello Forum,
The electromagnetic field EM must be treated relativistically because it travels at the speed of light...

Jul2614 10:16 AM
tom.stoer

3 
355 
Hey Everyone, Just wondering what would be a good experimental investigation involving a radioactive source and the...

Jul2614 01:36 AM
Nico123

3 
389 
Hi all,
I'm trying to compute the effect that a magnetic field has on the singlet and triplet states of positronium. ...

Jul2514 11:24 PM
"pi"mp

2 
312 
I have never been to the pyramids in Egypt. I'd love to go one day. I am sure their configuration will be just as...

Jul2514 09:17 PM
bhobba

13 
693 
Forgive me if some of my question sounds misguided or misinformed  I'm new to the flux pinning game.
I want to be...

Jul2514 08:58 PM
jtmarmon

0 
293 
Dirac left me in the dust at this step. Can someone please help me through it.
I understand from Susskind's...

Jul2514 08:43 PM
marcusl

5 
389 
Hi,
I'm entering graduate school this fall and was looking to improve my computational physics knowledge. I have...

Jul2514 08:00 PM
bhobba

1 
285 
Hey there
Im preparing for an oral exam in mathematical quantum physics.
not sure if this fits in here very...

Jul2514 03:44 AM
vanhees71

1 
330 
I've got a problem which is asking for the eigenvalues and eigenstates of the Hamiltonian H_0=B_0(a_1...

Jul2514 12:20 AM
Shyan

4 
401 
Just a simple question. How do we know the detector isn't messing up the double slit experiment when a single photon...

Jul2414 10:13 PM
atyy

70 
2,312 
So I've been selfstudying from Griffiths Intro to QM to get back in shape for graduate school this fall, and I guess...

Jul2414 09:25 PM
strangerep

1 
340 
On page 86 of The Principles of Quantum Mechanics, Dirac left me in his dust. I quote:
...

Jul2414 06:03 PM
Fredrik

2 
360 
Does modern physics allow for the existence of massless fermions?

Jul2414 12:43 PM
atyy

2 
343 
What exactly is all this 'matrix elements of vectors' stuff that Landau is talking about?
I don't mean to ask...

Jul2414 09:10 AM
atyy

1 
305 
Hello Everyone,
I am currently reading about when the Quantum Mechanical Theory becomes relevant. A term that...

Jul2414 07:29 AM
Bashyboy

4 
435 
I have a few problems understanding the double slit experience and the behavior of photos due to simple observation.
...

Jul2314 11:31 PM
bhobba

15 
506 
I am learning identical particles recently, but I have some problem interpreting what I am writing down. So if we have...

Jul2314 04:26 PM
Jano L.

5 
677 
The first postulate of quantum mechanics says that every physical system is associated with a separable complex...

Jul2314 08:27 AM
vanhees71

6 
674 
what is the INNER QUANTUM number ?

Jul2314 08:07 AM
bahamagreen

6 
538 
Hi all! I am wondering if there is an interpretation of QM where the future is "set in stone" (for lack of a better...

Jul2214 11:46 PM
bhobba

47 
3,037 
How do we know/observe a particle annihilating a antiparticle?
Is it impossible to theorize that in the early...

Jul2214 02:55 PM
phinds

4 
599 
I thought that it would be possible to get a single photon to a double slit which would be sufficiently coherent to...

Jul2214 10:28 AM
naima

11 
656 