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Feb2313 08:38 AM
ZapperZ

1 
30,373 
Hi people.
I just read this somewhere
and I can't get my head around it.
How is the Uncertainty Relation...

Apr1014 12:30 PM
Bill_K

1 
231 
How to you get sets of complete basis functions using group theory ? For example , using triangle group for CH3 Cl ?

Apr1014 11:27 AM
journeyman1986

2 
287 
From page 46 of "Modern Quantum Mechanics, revised edition", by J.J. Sakurai.
In equation (1.6.24),
\left = d...

Apr1014 10:35 AM
bassam

5 
779 
I understand that a photon can be 'absorbed' by an electron resulting in the electron jumping to a higher energy level...

Apr1014 02:43 AM
UltrafastPED

11 
477 
A few weeks ago I heard that Intel released 14nm CPU (Broadwell). After that I did some research and found out that by...

Apr914 07:55 AM
UltrafastPED

1 
231 
With the help of some kind PF folk I recently comprehended the idea of the quantum zeno effect. The idea now seems...

Apr914 04:23 AM
James MC

9 
364 
Hi folks!
Apparently
\Psi(x) = Ax^ne^{m \omega x^2 / 2 \hbar}
is an approximate solution to the harmonic...

Apr814 08:47 AM
vanhees71

6 
341 
I have read in a classical EM book:
" The picture of conduction electrons moving freely in conductors is an...

Apr814 04:04 AM
UltrafastPED

3 
241 
Hi, suppose that the operators $$\hat{A}$$ and $$\hat{B}$$ are Hermitean operators which do not commute corresponding...

Apr814 02:49 AM
dextercioby

19 
552 
There is an argument that accurate sequential measurement of conjugate observables A and B on the same state is...

Apr814 12:12 AM
Ken G

21 
588 
I think I understand it but I prefer a response from a sci advisor rather than whatever someone put up on wikipedia. I...

Apr714 10:10 PM
bhobba

1 
333 
If we consider a bipartite system as in EPRB experiment we get the probabilities :
p(++)=p()=1/4*(1cos(theta))...

Apr714 07:31 AM
jk22

7 
250 
Hi,
I was wondering if 2 electrons in an 1sorbital of a hydrogen anion (or alternatively neutral helium) are...

Apr714 03:59 AM
xortdsc

6 
398 
Instantaneous actionatadistance (which is how we explain quantum entanglement) implies eventsimultaneity, but we...

Apr614 06:08 PM
DevilsAvocado

21 
889 
Hi all!
I am currently reading a review "Area law for the entanglement entropy" by Eisert, Cramer and Plenio...

Apr614 05:16 PM
atyy

3 
309 
Is the transformation of an operator under INFINITESIMAL unitary transformation, U^1AU or UAU^1?? I saw that two...

Apr614 05:15 PM
Matterwave

3 
230 
Typical introductions to path integrals start with asking for the value of \langle x_1,t_1  x_2,t_2 \rangle. This is...

Apr614 04:35 PM
pellman

4 
245 
Hello!
I've only just come across the Unruh Effect...so please bear with me!
Say you have a long pole, and you...

Apr614 04:20 PM
craigi

5 
378 
I have read the follow bock
...

Apr614 02:57 PM
alejandrito29

0 
224 
according to sommerfield quantization rule "for any physical system in which the co ordinates are periodin functions...

Apr614 02:05 PM
Nugatory

1 
197 
Here's a puzzle that has been bothering me lately. I take as given the following:
E = h\nu (Planck) energy...

Apr614 10:25 AM
ZapperZ

2 
300 
This idea is brought on by this paper: http://arxiv.org/abs/1210.5646
and the idea proposed by Asher Peres:...

Apr614 09:52 AM
naima

3 
298 
I usually know how to manipulate bras and kets. But I probably found difficulty because of the double summation. How...

Apr614 07:15 AM
kith

7 
275 
As per Heinsburg uncertainity principle, Δx*Δp≈h. It means we cannot actually measure simentenously both position and...

Apr614 06:04 AM
HomogenousCow

8 
433 
I considered the covariance of 2 spin 1/2 as a non linear operator : A\otimes BA\Psi\rangle\langle\PsiB.
The...

Apr614 12:55 AM
jk22

7 
351 
I am an accountant, not a physicist, but I find physics pretty interesting. One thing that I see reported on many a TV...

Apr514 10:04 PM
bhobba

20 
650 
Hi All,
Would it be reasonable to state that, together with the quantum mechanics appearance, there appeared also a...

Apr514 09:44 PM
bhobba

8 
317 
I am a retired electrical engineer, now able to get back to studying what I really enjoy  mathematics and physics.
...

Apr514 08:05 PM
Ken G

5 
355 
My textbook says the ground state energy of the QSHO is given by 1/2*h_bar*w and that this is the minimum energy...

Apr514 01:37 PM
WannabeNewton

1 
174 
consider the finite square well: V = Vo between x=a and x=a, V=0 elsewhere
Now for scattering states,...

Apr514 12:54 PM
user3

0 
180 
Hey PF, i'm in my intro quantum course and was wondering if there is an intuitive reason why the allowed energies in...

Apr514 12:40 PM
PsychonautQQ

0 
136 
Consider this:
Two antennas are set up in a vacuum. They both radiate electromagnetic waves of the exact same...

Apr514 11:12 AM
user3

2 
154 
What would be the scale, in which Newtonian mechanics dissolve and QM becomes the sole victor for accurate...

Apr514 01:51 AM
UltrafastPED

3 
201 
Are the quantum mechanical terms "probability amplitude" and "probability density" used interchangeably?

Apr414 09:16 PM
jtbell

4 
245 
So starting from the time dependent schrodinger equation I perform separation of variables and obtain a time and...

Apr414 12:05 PM
Chopin

4 
259 
Hello, Hi There
I am trying to obtain the relations of the conserved charges of the stress tensor, it has 4, one is...

Apr314 03:33 PM
WarDieS

2 
237 
If a particle comes from +infinite and collides with a potential of the form :
V = ∞ , x < 0 (I)
V0 ,...

Apr314 02:03 PM
jaytech

1 
188 
Hi,
Are the multiverses that come up in some cosmological theories, e.g. inflation, in any way related to the...

Apr314 09:19 AM
craigi

6 
604 
Hello there.I am a master student in High Energy Physics. I am trying to get started in AdS/CFT and holography. I...

Apr314 02:36 AM
metamathphys

0 
190 
Hello.
Apparently for SU(N) gauge theories there is a perturvative approach call "large N expansion". I need a...

Apr314 02:25 AM
metamathphys

3 
340 