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Feb2313 08:38 AM
ZapperZ

1 
36,151 
Hi all, two questions. I don't have a physics background (but have a decent mathematical background, and have dabbled...

Dec1210 07:37 AM
jambaugh

17 
2,909 
I am a bit confused about the derivation of Planck impedance and why 29.9792458 ohms is a bound for anything... (I...

Dec1210 04:20 AM
Lednakashim

0 
773 
I wonder whether Dirac explanation of paradox of negative energy solutions
of his equation is viable. Of course this...

Dec1210 12:30 AM
shankar3274

1 
982 
Hi
Say I use my Hamiltonian to find some propagator G(\uparrow,\omega). Now I wish to find G(\downarrow,\omega)....

Dec1110 09:38 AM
Niles

0 
780 
Say we have a small box with two physically identical bosons in it. Is it true that if I partition the box in two...

Dec1110 03:42 AM
Cthugha

3 
1,688 
Hi
Came across a guy in a cafe today who asked the question, " Why is Schrodinger's equation complex?". No one knew...

Dec1110 02:08 AM
Dickfore

39 
7,426 
Hello, I'm taking a course in introductory modern physics, and I have a few questions on the nature of quantum...

Dec1010 08:47 PM
nonequilibrium

0 
1,916 
Consider one slit white light diffraction which produces rainbow fringe  black fringe  white fringeblack...

Dec1010 11:09 AM
jtbell

1 
774 
So here is this thing that i really really can not agree with (regarding experiments)! What Bell's theory states...

Dec1010 10:41 AM
DrChinese

93 
8,248 
Well as you guys may know, I watch a lot of Star Trek. In the shows, it often referres a Black Hole as a Quantum...

Dec1010 06:09 AM
julianC

17 
3,418 
Please forgive me if I am hideously wrong in any of my points. I am not terribly wellversed in quantum physics.
...

Dec1010 03:04 AM
Zarqon

1 
959 
The question occurred to me when I was thinking about black radiation. It is critically depend on the fact that the...

Dec910 10:58 PM
arielleon

4 
1,342 
Relativistic scalar particle might be described by KleinGordon equation, spin 1/2 particle
is described by dirac...

Dec910 03:27 PM
martinbn

5 
1,510 
Can anyone give me a reference to a paper with solution of Dirac equation in
uniform electrostatic field. I'm trying...

Dec910 02:55 PM
paweld

0 
719 
Can anyone tell me what is complex quantum mechanics and why we need it? I think we don't need creature complex qm...

Dec910 02:09 PM
ber70

1 
733 
I decided to go over the mathematical introductions of QM again.The text I use is Shankar quantum, and I came across...

Dec910 10:02 AM
kerrigan

2 
2,760 
I know this may be a completely stupid question and it's so fundamental but... As we all know the first thing we learn...

Dec910 01:53 AM
Talisman

4 
1,508 
So I'm pretty sure I understand the formalism of dual vector spaces. (E.g. there exist objects that operate on vectors...

Dec910 12:42 AM
Talisman

6 
2,730 
I'm not a professional scientist, just a software engineer with a fascination for how our world works. I thought I'd...

Dec810 10:25 PM
The_Duck

2 
742 
Suppose we have timedependent operator a(t) with the equaltime commutator
=1
and in particular
=1
with...

Dec810 04:10 PM
pellman

4 
1,616 
I am interested in learning the nature of the interaction between a photon and the atoms in a medium that has...

Dec810 04:02 PM
mathman

3 
1,677 
Hey guys I'm new here. I have a question about Planck lengths that has been bothering me lately. I'm not exactly well...

Dec810 01:59 PM
bapowell

3 
893 
First off, I'm no scientist or physicist, I don't have a fancy degree, I'm a computer engineer with an absolute...

Dec810 01:40 PM
Mommabear

7 
9,973 
What would happen if the Energy of the photons from the sun decreased by 10^60?
I think it means that the earth...

Dec710 03:32 PM
nismaratwork

2 
691 
Hi
Lets say I have a Hamiltonian which is invariant in e.g. the spin indices. Does this imply that spin is a...

Dec610 06:35 PM
bigubau

4 
1,021 
Please teach me this:
It seem Noether theorem say that a symmetry corespondant a conservation observation at...

Dec610 06:27 PM
bigubau

3 
1,310 
Hi All,
I am trying to remember the logical argument that leads from Heisenberg's uncertainty principle to the...

Dec610 06:21 PM
bigubau

6 
2,340 
Hi . In weinberg's QFT book 1st volume he states that any operator can be expressed as a sum of products of...

Dec610 06:13 PM
bigubau

2 
921 
In quantum optics, I've been looking at how one can show electromagnetic field is equivalent to a harmonic oscillator....

Dec610 05:42 PM
Master J

0 
923 
Could anyone please tell me how to calculate quadrupole quadrupole interaction between two molecules having dipole...

Dec610 11:27 AM
Vanadium 50

9 
7,521 
I am new to quantum physics.
Is there is any operator in quantum physics that does not show eigenvalue property?...

Dec610 03:38 AM
sancharsharma

8 
1,376 
I am fairly new to particle physics and am puzzled by an abbreviation I often see in Lagrangians here (though it may...

Dec510 11:53 PM
chrispb

2 
4,083 
I have read the statement that 'the wavelength of the photons used in imaging an object needs to be much larger than...

Dec510 11:04 PM
fred1234

7 
2,424 
My understanding is:
A) If a photon strikes an atom and the photon has exactly the correct amount of energy to move...

Dec510 03:50 PM
fred1234

24 
4,112 
Hi
I am, at the moment, reading about propagators and Green's functions in QM. An example of a Green's function in...

Dec510 02:40 PM
Niles

4 
947 
Hi,
If the normalized 1D wavefunction of hydrogen atom for n=1, l=0, m_l=0;
\psi_{1s}(x)=\frac{1}{\sqrt{\pi}...

Dec510 07:49 AM
torehan

8 
1,900 
I dont really get the part that we shouldnt "imagine" quantum mechanics .I mean, I know what eigenvectors are in three...

Dec510 06:44 AM
the_house

5 
996 
I have just finished Black Holes and Time Warps by Kip Thorne as part of a high school reading class. Regardless of my...

Dec410 09:14 PM
Vorde

0 
1,068 
Say we have two complex fields, f_1 and f_2 which each are solutions of the D'Alembert operator or the wave operator...

Dec410 08:08 PM
Spinnor

0 
800 
Haste made waste (I managed to get it precisely backwards, sorry. Corrected below. And please, somebody, clue me in...

Dec410 04:43 PM
lmerriam

0 
714 