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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
36,791 
what do we mean by spin of a particle when we say it a point particle?how do we measure spin experimentally and give...

Aug2112 12:01 AM
Drakkith

16 
2,986 
Is quantum entanglement unaffected by fields/forces?
Forces = the, yet known, four fundamental forces
i.e. Is...

Aug2012 07:39 PM
QuantumHop

4 
1,663 
Hello,
I'm interested in (typically topological) QFTs arising from Lagrangians which are pure constraint, ie. of...

Aug2012 05:24 PM
TMM

0 
324 
Consider the simplest of all possible atoms: A hydrogen atom with only a proton as its nucleus.
According to...

Aug2012 08:43 AM
DrChinese

4 
898 
Alice and Bob build a quantum entanglement experiment with the help of a lab technician.
The experiment runs and a...

Aug2012 08:15 AM
QuantumHop

5 
1,042 
do the photons have mas???or just the momentum???or both??

Aug2012 01:34 AM
tom.stoer

1 
361 
This topic has been extensively discussed on this forum during the last few years, but I don't see much discussion on...

Aug1912 07:23 PM
alexepascual

2 
1,655 
I'm selfstudying Griffith's Intro to Quantum Mechanics, and on page 100 he makes the claim that the eigenfunctions of...

Aug1912 10:39 AM
Ilmrak

5 
692 
this is from Omnes' book Understanding QM
Has this problem been resolved or is it still outstanding?

Aug1912 06:11 AM
mfb

7 
768 
I was reading this article, http://www.nature.com/news/2009/090122/full/news.2009.50.html, and it was talking about...

Aug1912 12:58 AM
Allojubrious

2 
575 
I finally got an answer to my question by a poster on this site, and my thread gets removed. I broke no rules, so it...

Aug1812 10:37 PM
jtbell

1 
540 
We know the universe is not in a supposition state, so the wavefunction of the universe must have collapsed at some...

Aug1812 09:13 PM
ZapperZ

5 
973 
Does FTL transmission of information (via 1 entanglement or 2 any means) violate causality?
FTL = faster than light...

Aug1812 07:09 PM
bohm2

22 
6,898 
Hi,
I'd appreciate your help about this: Is someone capable of explaining how attractive forces work in three...

Aug1812 06:00 PM
morg

2 
561 
For a particle to travel from point A to point B at the smallest scale, is there a distance in which the particle has...

Aug1812 03:36 PM
Naty1

3 
658 
http://i1251.photobucket.com/albums/hh555/glemaitre/Screenshot20120818at42446AM.png
what does Re refer to? I...

Aug1812 04:06 AM
g.lemaitre

2 
474 
Does anyone have a calculation that can calculate a particle wave function over 1 planck time interval?

Aug1712 10:18 PM
hubble_bubble

3 
1,432 
Hi,
I am was reading about a double well potential. I came across the word "quantum tunnel splitting". Can anyone...

Aug1712 04:36 PM
Bill_K

1 
1,079 
halfway page 41 Bohm obtains for the action variable
J = 2\int_{a(E)}^{b(E)} dq \sqrt{2m}
Then he obtians the...

Aug1712 02:33 PM
A_B

2 
496 
What is the relationship between acausality and randomness?
Let's look at the argument below:
For something to...

Aug1712 02:01 PM
JPBenowitz

49 
3,901 
Hi,
I am trying to study Quantum Field Theory by myself from Mandl and Shaw second edition and I am having trouble...

Aug1712 05:09 AM
shahbaznihal

8 
1,291 
Consider two Hermitian operator A, B; Define
=iC,
then operator C is also Hermitian.
we calculate the...

Aug1712 04:45 AM
arojo

7 
1,103 
Hi friends
I am trying to drive constraints of a Lagrangian density by Dirac Hamiltonian method. But I encountered...

Aug1712 12:14 AM
tom.stoer

3 
659 
I am aware that physicists are trying to derive born rule from unitary evolution. Has there been any success? What is...

Aug1612 06:48 PM
bhobba

7 
1,097 
We know that momentum is proportional to k so by adding more waves
to localise our particle we are adding more waves...

Aug1612 12:19 PM
Sam Wong

4 
1,268 
Doesn't the Bohr model use standing waves as a reference? Before De Broglie's hypothesis, how did Bohr manage to...

Aug1612 11:11 AM
Lamarr

2 
1,004 
significance of commutation of operators?
how do u show that the position and momentum operators do not commute?

Aug1612 07:40 AM
Simon Bridge

3 
573 
difference between eigenvalue and an expectation value of an observable. in what circumstances may they be the same?
...

Aug1612 06:34 AM
Ilmrak

1 
2,448 
I need a simple, intuitive, and easytocomprehend example of a POVM measurement, which is not a projective...

Aug1612 05:11 AM
Demystifier

6 
1,116 
i was going through the diffraction experiment and had a question that i would like to ask:
suppose i am performing...

Aug1612 04:18 AM
nouveau_riche

4 
740 
why is only one component of angular momentum is quantised, and what determines which component is quantised?

Aug1612 12:44 AM
Jorriss

3 
789 
The Quantum Theory of Fields, Steven Weinberg, P.120
above 3.3.24, it says,
If the matrix elements of W between...

Aug1512 11:56 PM
Sam Wong

3 
668 
Does anybody could help me to state if the following particles experience strong interactions, weak interactions, both...

Aug1512 11:47 PM
jarod765

5 
962 
http://i1251.photobucket.com/albums/hh555/glemaitre/Screenshot20120815at102228PM.png
I don't see how they know...

Aug1512 11:22 PM
g.lemaitre

2 
779 
Hi all my interest in Physics is purely a hobby and I have to say I have gaps in my knowledge but even then I have a...

Aug1512 06:40 PM
Naty1

3 
711 
how is the wavefunction of 1D infinite well modified by the application of an electric field to the well.

Aug1512 10:12 AM
shahbaznihal

2 
614 
http://books.google.rs/books?id=vrcHC9XoHbsC&pg=PA188&lpg=PA188&dq=Nolting+Heitler+London+method&source=bl&ots=5uRHg3gG...

Aug1512 09:04 AM
LagrangeEuler

2 
475 
How can one operate the deltas of the uncertainty relation? I know they're supposed to be the standard dev, but how...

Aug1512 09:00 AM
ImaLooser

3 
628 
I'd like to find out more about A. Neumaier's interpretation of quantum mechanics.
How?

Aug1512 08:46 AM
ImaLooser

3 
694 
are observables only those quantities which commute with system's Hamiltonian ?

Aug1512 07:58 AM
bhobba

10 
1,402 