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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
35,449 
why doesn't the uncertainty principle lead to small discrepancies in the spectrum of the same element in different...

Jul613 12:48 AM
Simon Bridge

1 
486 
I've been thinking about this for a while. I believe I have some misconceptions about light.
Let's say we have a...

Jul513 10:47 PM
wotanub

4 
582 
Hi, I am slightly confused with the term, ionization energy (IE). I am stuck between two definitions, one is the...

Jul513 03:36 PM
cgk

3 
427 
According to the Einstein lightquantum hypothsis, the photon energy is given by E = hbar*ω. If taking the photon as...

Jul513 12:04 PM
Naty1

13 
1,350 
As i understand the outcome of the double slit experiment is firstly the Photons of light that were fired have no true...

Jul413 05:34 PM
Maui

5 
647 
Just want to clarify my understanding of these things.
Fermions obey the Pauli Exclusion Principal, meaning...

Jul413 05:11 PM
Maybe_Memorie

2 
479 
I am studying an article http://arxiv.org/abs/quantph/9907069 and having some problems understanding it.
Is...

Jul413 03:14 PM
lugita15

19 
1,362 
First a little intro.
The process of renormalization introduces in a QF theory a renormalization scale μ. Physical...

Jul413 02:58 PM
Avodyne

1 
296 
I'll write down what i know and point it out if I'm wrong.So we normalize the wave function because ∫ψ(x,t)^2dx...

Jul413 12:32 PM
jtbell

1 
519 
I look at wikipedia.org/wiki/Bell_state
and use the same notations.
The article says that there are just 4 Bell...

Jul413 11:51 AM
naima

2 
418 
Relativistic Quantum Mechanics exist. But I don´t understand, it would must be see contradictory. He has the locality...

Jul413 10:01 AM
bhobba

21 
1,895 
Folks,
If somebody has this article "W. A. Fedak and J. J. Prentis, “Quantum jumps and classical harmonics”, Am. J....

Jul413 09:46 AM
frowdow

0 
556 
Recently I read some mainstream journals reporting about superluminal transport of EM energy; they say that is a...

Jul413 09:24 AM
mfb

4 
512 
In the paper by eisenberg et. el.
http://arxiv.org/abs/1209.4191
Photon 1 and 2 are entangled.
Then 1 is...

Jul413 05:02 AM
San K

1 
602 
This came across my mind today, I am not sure if it's been proposed/invalidated before. I don't have enough physics...

Jul313 08:31 PM
Vanadium 50

1 
397 
I am confused about what I think should be the most basic concepts in quantum mechanics..
As far as I understood, a...

Jul313 02:30 PM
V0ODO0CH1LD

7 
660 
As a result of some precise experimental data, we now know that the mass of the quark is not naively 1/3 the mass of...

Jul313 01:39 PM
Bill_K

17 
1,368 
Hi pf, i have been wondering what differentiates QED Vacuum from QCD Vacuum? How would u explain its implications? I...

Jul313 12:11 PM
tom.stoer

10 
991 
Hi,
I read the following in an online source:
In relativistic settings, momentum and energy are equal so the...

Jul313 11:35 AM
Bill_K

2 
323 
i do not posses deep knowledge of Quantum physics nor regular physics for that mater novice at best. so i have a idea...

Jul313 09:25 AM
bhobba

4 
498 
Hello,
I am buying the equipment to build a lab that will test Bell's Inequalities. A laser beam is polarized, then...

Jul213 05:30 PM
stewarc8

0 
319 
(Part of) The proof/logic of Bell's theorem goes thus:
With the measurements oriented at intermediate angles...

Jul213 03:37 PM
DaleSpam

428 
33,857 
It just occurred to me that I don't know why composites of interacting particles are always in entangled  as opposed...

Jul213 09:33 AM
metroplex021

4 
551 
Is there an intuitive explanation of why E/w = 2*L, where E/w is the ratio of the energy of any photon to its angular...

Jul213 09:22 AM
msumm21

5 
572 
The model of damped harmonic oscillator is given by the composite system with the hamiltonians ##H_S\equiv\hbar...

Jul113 10:02 PM
rbwang1225

1 
506 
MRIs are used in medicine for diagnostic imaging. I am told it has something to do with protons. But in the human...

Jul113 09:37 PM
krome

1 
369 
http://www.sciencenews.org/view/feature/id/351277/description/When_the_atom_went_quantum
It has been 50 years since...

Jul113 04:51 PM
vanhees71

3 
713 
I refer to the attached setup.
If we have one photon (with H> polarisation) coming in one direction towards the...

Jun3013 02:02 PM
StevieTNZ

0 
377 
Hi there  can anyone give me, or point me to, an argument that the reduced state density matrix corresponding to one...

Jun3013 02:00 PM
metroplex021

2 
446 
How this is defined?
##\vec{r}\cdot \vec{\sigma}##?
where ##\vec{r}=(x,y,z)## and...

Jun3013 01:28 PM
conana

2 
445 
I'm looking for a book on QFT that is both introductory and somewhat rigorous. I have Zee's book but for me it is...

Jun3013 10:40 AM
Bill_K

1 
374 
I had posted this question here : http://physics.stackexchange.com/q/69003/540
I guess its appropriate to post...

Jun3013 10:13 AM
The_Duck

1 
430 
Srednicki eqn. (2.23) and (2.24) states: We can make this a little fancier by defining the unitary spacetime...

Jun3013 07:25 AM
omephy

2 
629 
Sorry for my abysmal level of ignorance, but I'm not understanding why quantum tunneling from nothing is considered a...

Jun2913 04:51 PM
ZapperZ

2 
422 
Hello everyone,
a number of books and web articles says that the minimum field required is ≈10^7V/cm for electrons...

Jun2913 08:30 AM
ZapperZ

3 
547 
Hi :)
In this lecture (http://www.youtube.com/watch?v=Igl8hE3Eac0), susskind talks about attractive the force...

Jun2913 05:09 AM
FredericGos

3 
631 
Hello everybody, I am a first year student and I have a question about tunneling.
If we have an electron which is...

Jun2813 11:59 PM
Simon Bridge

9 
988 
Do the units of a wave function vary? i have heard that it just joules. What do you think?

Jun2813 02:40 PM
dextercioby

11 
1,216 
In Zee's QFT book he writes an amplitude as:
M(p)=\lambda_0+\Gamma(\Lambda,p,\lambda_0)
He then states that you...

Jun2813 08:51 AM
andrien

1 
486 
Say I have a particle in the rest frame with spin up in the z direction. If I boost the system in x direction, does...

Jun2813 07:13 AM
DrDu

16 
1,168 