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Feb2313 08:38 AM
ZapperZ

1 
35,548 
A lot of textbooks give the definition of an Smatrix element as:
\langle \beta_{out} \alpha_{in}\rangle = \langle...

May1114 10:37 PM
Einj

7 
365 
How are the two related mathematically ie
QV is SpaceTime devoid of matter and has Zero Point Energy on one hand
QF...

May1114 09:22 PM
Simon Bridge

9 
399 
If leptons can stack up on top of each other and not interfere than how can a single lepton do so in the two split...

May1114 09:14 PM
Simon Bridge

12 
611 
I am writing an undergrad (Bachelor) thesis covering the harmonic and anharmonic oscillator using path integrals on...

May1114 02:32 PM
magnetic flux

0 
281 
Hi there!
I have tried for hours to calculate the commutator of angular momentum in the differential form, but I...

May1114 09:15 AM
Chem.Stud.

5 
324 
I am aware that the most popular version of the quantum brain theory i.e. the Penrose and Hameroff version has been...

May1114 04:16 AM
Frank Weil

16 
1,151 
If we suppose we have an entangled pair in position/momentum and, following the argument, we measure position of...

May1014 01:04 PM
jk22

22 
1,244 
Hey, I'm just reading through from AP notes and was slightly confused about selection rules.
It's my understanding...

May914 11:52 PM
meriadoc

0 
270 
So I've just been reading about the SternGerlach apparatus/experiment and had some questions about the half spin...

May914 07:11 AM
Orodruin

1 
318 
Why is it that we observe a continuous spectrum in blackbody radiation not discrete spectral lines dependent on the...

May914 04:51 AM
Bill_K

2 
358 
I'm reading a book on Path Integral and found this formula
\int_{\infty}^{\infty...

May814 10:59 PM
strangerep

6 
405 
Hi.
Quantum states are usually represented as vectors, and treated as such, even when distinct states should be...

May814 04:54 PM
dextercioby

4 
346 
Hi. I never understood why the momentum wave function ##\phi (p)## is the fourier transform/integral of the real space...

May814 01:26 PM
Matterwave

11 
786 
Quantum teleportation lets you send quantum information over a classical communication channel by using...

May814 12:07 PM
Strilanc

8 
510 
Here's a puzzle that has been bothering me lately. I take as given the following:
E = h\nu (Planck) energy...

May814 06:31 AM
bhobba

10 
810 
For hydrogen atoms, all book take correction up to 1/c^2 where the perturbation is P^4/8*m^3*c^2. And they go solving...

May714 11:42 PM
M. next

4 
338 
I would appreciate if someone could set me straight here. I understand if I have an arbitrary operator, I can express...

May714 05:37 PM
MisterX

1 
291 
Has anybody seen this theory before, If so, do you have more information on it.
"An introduction to the tomographic...

May714 05:33 PM
atyy

4 
550 
Can someone explain the cause behind photobleaching (http://en.wikipedia.org/wiki/Photobleaching) of fluorophores when...

May714 04:54 PM
Bashkir

6 
279 
I have a partition function in euclidean quantum field theory. I have a parameter, let's say a charge, that I can...

May714 03:23 PM
santale

4 
287 
Why did the author of the book choose the combinations in (9.66) and (9.67) as follows? Why didn't he choose some...

May714 10:24 AM
M. next

9 
347 
I'm just posting the bare bones of this experiment to begin with, as it was quite the task just to attach all the...

May614 01:12 AM
fizixfan

4 
629 
I wonder, what the physical meaning to electron correlation in molecular systems? and. Is there many types of it?
...

May514 04:12 PM
bsmile

5 
3,908 
The major problem I have with hidden variable theories is this: Even if you find hidden variable solutions which...

May514 10:54 AM
PhilDSP

7 
624 
Hi,
So, I am working through section 5.2 of Sakurai's book which is "Time Independent Perturbation Theory: The...

May514 10:15 AM
Bill_K

3 
322 
Hawking radiation suggests that the antiparticles enter the black hole and annihilate with the normal matter in the...

May514 05:56 AM
haael

2 
322 

May514 01:42 AM
fizixfan

1 
257 
how to go step by step from the classical lagrangian to the schrodinger equation?
i would like to work with the...

May414 03:07 PM
WannabeNewton

5 
310 
Well this is a doubt that comes from some time ago and I haven't found the answer on the net. Quantum fluctuations in...

May414 02:59 PM
pabloxd43

2 
328 
Hi all,
I am reading this Zeilinger paper
Look at fig 1. There are four detectors D1 D2 D3 and D4.
When one of...

May414 02:18 PM
forcefield

1 
276 
I was watching Fay Dowker's "Spacetime and the quantum: united by history" on Youtube, and a question occurred to me....

May314 12:44 PM
ftr

7 
552 
Hi,
I was wondering if it is possible to compute e.g. bohr radii for a metric system whose correspondence to real...

May314 11:06 AM
xortdsc

2 
269 
Can someone explain to me what is wrong with the following argument? There are two parts. First of all, KS, despite...

May314 05:24 AM
bhobba

1 
272 
I understand that a local gauge transformation functions to conserve the energy of an electron as it moves through...

May214 10:07 PM
bhobba

1 
326 
The Schrödinger equation rotates the state vector in Hilbert space continuously (i.e. without jumps). This makes sense...

May214 09:27 AM
kith

15 
671 
I red griffiths many times but even now there is something I can't understand. It's about statistical interpretation....

May214 04:47 AM
vanhees71

11 
452 
Hey there,
I'm having trouble understanding where two of the formulas for angular momentum of an electron in the...

May214 12:03 AM
richardhale

8 
447 
DO try this at home! I took three pieces of polarized film (which I salvaged from a pair of 3D glasses). First I put...

May114 12:44 PM
fizixfan

22 
1,143 
In Srednicki's QFT textbook, equation 9.6, he writes:
Z=e^{i \int d^4x \, \mathcal...

May114 11:38 AM
andrien

4 
486 
(http://en.wikipedia.org/wiki/Superdense_coding) is a way to send 2 classical bits by sending only 1 qubit and...

May114 10:34 AM
Strilanc

1 
242 