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Feb2313 08:38 AM
ZapperZ

1 
34,048 
Hey everyone.
I have a couple of question regarding wave function collapse.
I can accept that one cannot make...

May2614 10:38 PM
atyy

6 
313 
I'm in the first of 3 courses in quantum mechanics, and we just started chapter 4 of Griffiths. He goes into great...

May2614 10:15 PM
jayqubee

5 
350 
Hi. I am reading a book entitled "AtomPhoton interactions" by Claude CohenTannoudji, et al.
There is a symbol...

May2614 08:50 PM
UltrafastPED

1 
181 
"Locally, the spin density S is an intrinsic (i.e. originindependent) quantity, which is associated with the local...

May2614 06:38 PM
UltrafastPED

2 
265 
Am I right to think that particles cooled asymptotically to 0 K would have wave functions the size of galaxies or even...

May2614 04:59 PM
QuasiParticle

11 
446 
Why is it the case that dual field tensors, e.g. \widetilde{F}^{\mu\nu}=\frac{1}{2}\epsilon^{\mu\nu\rho\sigma}F_{\rho...

May2614 11:53 AM
guest1234

6 
283 
To which type of Fundamental forces below the Pauli's exclusion belong?
Strong nuclear forces
Coulomb forces
Weak...

May2614 10:47 AM
cgk

4 
443 
I have read a number of books on quantum mechanics and I am now at peace with the idea that the wavefunction of an...

May2614 10:26 AM
Mikeal

3 
272 
Here is an ultra short repeat of the Zeno Paradox, but please google it for a longer version with pictures etc:
...

May2614 08:37 AM
DaleSpam

7 
490 
Hi! So let's say we measured the angular momentum squared of a particle, and got the result ##2 \hbar^2##, so ##l=1##....

May2514 11:22 PM
strangerep

6 
288 
Suppose we have a system with M nuclei and N electrons
the electron density is defined as:
...

May2514 05:57 PM
ChrisVer

10 
391 
Does the measurement problem ("wave function collapse") or something similar somehow manifest itself in QED and other...

May2514 09:47 AM
DrDu

44 
1,284 
In the operation $$U(\Lambda){\bf p}\rangle={\Lambda\bf p}\rangle,$$ if we define the state covariantly, $${\bf...

May2414 02:51 PM
Bill_K

2 
187 
I'm an electronics engineering student and I've only had a introductory onesemester course to quantum mechanics, so I...

May2414 01:17 PM
UltrafastPED

5 
449 
hello
i have to proof that Px (linear momentum operator ) is hermitian or not
i have added my solution in...

May2414 10:31 AM
Paul Black

5 
316 
In other words, must \mathcal{L}=\mathcal{L}^\dagger always be valid?

May2314 09:04 PM
dextercioby

5 
294 
Greetings. I thought about how/ why light propagates slower trough matter than vacuum. Generally it is excepted that...

May2314 08:14 PM
Vanadium 50

4 
219 
How is an ancillary bit used in a logic gate? I looked at
http://en.wikipedia.org/wiki/Ancilla_(quantum_computing)...

May2314 09:59 AM
BlackHole213

2 
272 
I have a couple of questions about entanglement and decoherence!
1. Sometimes you read that, strictly speaking,...

May2314 04:28 AM
Demystifier

2 
336 
Forming the supersymmetric string using superfields and superspace, Polchinski claims that the function
$$
G \sim...

May2214 07:25 AM
Illuminatum

0 
211 
Hi.
I've been learning quantum mechanics from different sources and I'm starting to notice that they have really...

May2214 07:04 AM
carllacan

30 
798 
I read today about Ehrenfest's theorem on mechanical systems (with adiabatic hamiltonian evolution).
Well in the...

May2214 05:01 AM
PhilDSP

7 
284 
If a system is made up by two subsystems, for example, the atom and the photon. and let's assume the state of the...

May2214 12:09 AM
micromass

3 
340 
Higher dimensional groups are parametrised by several parameters (e.g the three dimensional rotation group SO(3) is...

May2114 07:29 PM
Matterwave

21 
730 
I'd like to ask a question to the members of the Quantum Physics board.
Reading several articles regarding Quantum...

May2114 01:56 PM
ZapperZ

1 
293 
The energy changes correspond to infrared, h_bar * w.
Which particles are actually oscillating? The neutrons or the...

May2114 11:28 AM
ChrisVer

6 
400 
In euclidean quantum field theory, the imaginary part of the free energy, defined as the logaritm of the partition...

May2114 09:14 AM
LLSM

1 
320 
why are physisist having so much trouble quantising gravity and getting it to fit into QFT?

May2014 11:32 PM
atyy

2 
390 
I've never really been...convinced...of the statement
$$\bf{J}=\bf{L}+\bf{S}$$
I've always just gone along with...

May2014 10:24 PM
Ravi Mohan

11 
453 
Let ψ be a wavefunction describes the quantum state of a particle at any (x,t), What does ψ* i.e, the complex...

May2014 07:26 PM
UltrafastPED

6 
240 
Hi everyone,
Lately I have been reading about the double slit experiment, I am wondering if it would be possible to...

May2014 06:10 PM
mfb

3 
324 
I'm trying to get my head around this spin idea, the idea that particles behave like tiny dipole magnets when passing...

May1914 01:14 PM
Jilang

25 
934 
The definition of tensor operator that I have is the following: 'A tensor operator is an operator that transforms...

May1914 10:51 AM
CAF123

3 
379 
I am reading an intriguing article on rigged Hilbert space
http://arxiv.org/abs/quantph/0502053
On page 8, the...

May1914 06:04 AM
Ravi Mohan

2 
169 
Why, in a Gaussian wave function the position and momentum expectation value coincide to be zero?
Does it have any...

May1914 03:52 AM
BruceW

2 
225 
I have seen this question somewhere.. I diidnt get the answer. So plz help me.
In how many ways three identical...

May1914 02:08 AM
kashokjayaram

6 
582 
There are many cases, for simplicity, we choose the wavefunctions to be real. For example, in...

May1914 01:10 AM
DrDu

2 
278 
Could someone provide me with simple answers to the following questions? I have tried to find the answers on the...

May1714 09:58 PM
Simon Bridge

1 
337 
i mean, people are creating LHC to split the atoms, but why don't we just spin it? spin in in high speed and see if a...

May1714 02:30 PM
mfb

1 
291 
I read a sentence that says if a spherical volume in placed in a quantized space then the maximum entropy of the...

May1714 01:09 PM
Jilang

4 
261 