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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
36,811 
Or "what are particles good for?"
Particles (as defined in the Bohm interpretation) exist, have welldefined...

Aug1608 12:49 AM
DrChinese

46 
5,038 
first, Id just like to say that Im a 4th year physics major, so Ive taken QM and GR and have a pretty good...

Aug1508 03:38 PM
Fredrik

15 
4,635 
how does dimensional regularization work ?
i see , how can you calculate integrals in ddimensions of the form
...

Aug1508 01:01 PM
Avodyne

1 
1,836 
A swaptest is described here...

Aug1508 12:16 PM
Dragonfall

1 
2,760 
Hey guys, I wanted to know if there is any other (more physical math) reason why schrodinger's equation is not valid...

Aug1508 10:55 AM
cathalcummins

31 
8,678 
I am having trouble understand why the kleingordan eqn is accepted to describe spin 0 particles since it gives the...

Aug1508 09:58 AM
clem

2 
1,135 
Hi!
Has anybody seen the perturbative expansion of the generating functional of QCD Z expressed with Feynman...

Aug1508 04:56 AM
Sunset

6 
1,508 
is hv as we all know, but how do with derive it from Einstein's special theory of relativity? any pointer to help me...

Aug1508 03:25 AM
cesiumfrog

15 
2,517 
Hi there!
I'm struggling a bit with running couplings. Srednicki introduces dimensional regularization and the...

Aug1408 03:37 PM
Avodyne

1 
1,376 
reading...http://en.wikipedia.org/wiki/Fuzzy_logic the question is if we must stablish the fuzzy logic as a method to...

Aug1408 10:03 AM
mangoo87

2 
6,118 
Hi.
I have some basic (naive, ignorant) questions regarding the empirical nature of quantum particles. That is, in...

Aug1408 06:58 AM
ShaneS

12 
1,758 
It is often said that the field operator \hat{\phi}(x) of some free field theory, e.g. KleinGordon or Dirac, acting...

Aug1308 10:07 PM
Hans de Vries

52 
6,868 
My knowledge of QM is far from great, but I can't figure out what I'm missing here.
When looking for e.g. an...

Aug1308 07:02 PM
DieCommie

3 
1,039 
Currently I am working through a script concerning QFT. To introduce the concept of canonical filed quantisation one...

Aug1308 05:23 PM
Hans de Vries

5 
2,587 
my question is let be the integral , with \Lambda \rightarrow \infty
\int_{0}^{\Lambda} dp...

Aug1308 01:52 PM
mhill

0 
958 
Are they real are what? I've read in various places on the internet that there is a vast amount of energy stored in...

Aug1308 01:09 PM
H0T_S0UP

3 
1,502 
could anyone suggest the methods for solving the energy eigenvalues in a 1d finite potential well. are there any...

Aug1308 07:41 AM
G01

1 
1,606 
Hallo,
I would like to know why physicists are always seeking for irreducible representation of a given group. I...

Aug1208 08:34 PM
Fredrik

10 
1,393 
Hi
I was interested in Quantum Mechanics so I started reading some books about it.
When I was reading about...

Aug1208 04:40 PM
lightarrow

1 
972 
what does it mean when somebody says that a particle is on its mass shell? I have somewhat but not full understanding...

Aug1108 06:06 PM
cosmik debris

2 
3,599 
I'm running a simple limiting case of a simulation with the expression:
exp(i*H*t), where H is the hamiltonian, in...

Aug1108 04:39 PM
CompuChip

1 
994 
When the depth of a quantum well increases, the first level increases or decreases its energy with respect of the...

Aug1108 03:51 PM
jtbell

7 
2,011 
hey everyone, My names aaron and im a year 12 student studying physics. We have to learn about both the wave and...

Aug1108 09:53 AM
Usaf Moji

14 
12,912 
In photon polarization placing a horizontal polarizer in a beam of randomly polarized photons allows only half the...

Aug1108 09:48 AM
DrChinese

9 
1,826 
Suppose you have a fine layer of dust facing perpendicular to a strong gravitational body. If gravitons are point...

Aug1108 12:41 AM
Landru

0 
1,284 
Why shud one take the Fourier transform of a wavefunction and multiply the result with its conjugate to get the...

Aug1008 09:49 PM
G01

2 
1,290 
Hello. I'm a 15 year old student interested in theoretical physics. I took Calculus I in 7th grade at Hood College,...

Aug1008 04:44 PM
excogitator

2 
1,199 
I was watching a video about Quantum Mechanics and the double slit experiment which shows electrons to be both a wave...

Aug908 09:08 PM
JayHarryBeck

10 
6,543 
Hi everybody,
I was just wondering if humans have discovered the fundamental nature of matter (or energy). If not,...

Aug808 08:30 PM
jtbell

2 
3,971 
The explanations I have found in quantum mechanics books as to why the momentum operator is considered to be the...

Aug808 06:22 PM
cathalcummins

69 
10,686 
Hi  could someone briefly explain a Feyman Diagram (example?). Does this replace one or more complex QED model(s)? ...

Aug808 05:04 PM
Simone_beet

2 
1,724 
Hi all,
I've been looking at the problem of two interacting electrons in a 1D infinite well and wanted to run my...

Aug808 04:53 PM
badphysicist

1 
1,311 
How do you entangle photons?

Aug808 07:24 AM
jtbell

4 
7,578 
Hello
Im having 2 questions
I'm investigating NIR light propagation in tissue such as the skin and my question is:
...

Aug808 06:13 AM
evidenso

1 
937 
Have anyone done the GHZ experiment? As I understand it from a book I read QM predicts detections that hidden...

Aug708 02:56 PM
uknwe

7 
2,750 
Are there any particles (atomic, subatomic) that on average travel very slowly? As in, why is it that photons,...

Aug708 01:26 PM
clem

2 
1,058 
This is a fairly simple question, but the first such question I have done. Inorder to check my work I was hoping...

Aug708 10:41 AM
Marthius

7 
2,584 
Maybe I don't even have the terminology correct for this... I'm a quantum physics noob :)
My question is this: ...

Aug708 09:25 AM
DrChinese

3 
1,287 
At low velocity the group velocity is double the phase velocity (velocity of de Broglie waves). But phase velocity is...

Aug708 12:24 AM
cesiumfrog

1 
1,108 
Hi!
I wonder if the Feynman rules in momentum space can also be applied to disconnected diagrams. So aussume I have...

Aug608 02:32 PM
Sunset

0 
2,404 