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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
36,187 
There's a lot of talk about "virtual particles" and of energy conservation within a normal perturbative aproach to QM....

May1606 12:29 PM
reilly

2 
1,532 
I read of an experiment in which people actually timed how long it took water to boil, if it was watched and not...

May1205 05:06 PM
gonzo

14 
6,381 
A detector is a device that once it absorbs a minimum amount of energy changes its state and returns data to an...

May2610 12:42 PM
my_wan

21 
2,470 
I was taught that a particle is assigned to a unique quantum state. As a specific example, two bound electrons can't...

Nov912 07:26 AM
andrien

9 
1,356 
In Brian Greene's book 'The Fabric of the Cosmos' he introduces an experiment called the "delayedchoice quantum...

Jan1709 03:54 PM
JesseM

11 
811 
there is a way to write the expansion (in terms of self energy and bare propagator) of the dressed propagator without...

Nov2112 11:34 AM
paolorossi

0 
461 
I sometimes see these words used to describe puzzling aspects of quantum mechanics. Can someone explain exactly what...

Aug1012 08:06 AM
Naty1

7 
1,015 
I'd like to find out more about A. Neumaier's interpretation of quantum mechanics.
How?

Aug1512 08:46 AM
ImaLooser

3 
677 
Griffiths's QM textbook says on page 236 regarding the fine structure constant calculation from first principles:
...

Mar709 12:51 PM
confinement

1 
729 
I read some paragraphs from Michio Kaku's Hyperspace about Abdus Salam's illustration of symmetry breaking using a...

Jul704 05:58 PM
Tyger

2 
1,383 
Hello everyone,
I am trying to solve timedependent LiouvillevonNeumann equations for the dynamics of an electron...

Jun2312 09:20 PM
Einstein Mcfly

4 
971 
according to uncertainity relation product of dE*dt >=h/2*pi this defines the time limit to which energy conservation...

Oct1810 03:28 PM
khs1

0 
783 
in the schrodinger equation the integration constant in the angular wave
equation is set to L(L+1).
may i know why...

Mar2411 01:07 PM
clem

3 
843 
We have seen this famous relation between particle's momentum and its wave length as
p=h/λ
Can we interpret its...

Sep2011 09:30 AM
Naty1

1 
668 
Hi everyone,
I am doing some calculations related to elastic Pion  nuclei scattering in the Eikonal model and have a...

Nov1513 08:51 AM
k54ledung

0 
524 
Hi there, you know there are simple mathematical calculations, rather based on arithmetic properties (module,...

Aug2509 10:27 AM
snnmbr

2 
1,824 
is the idea that collapse cannot be defined as something that occurs, generally known and accepted?
thx

Mar1306 11:05 AM
alfredblase

12 
1,169 
Since my discussion with Juan R in the thread "photon's mass is zero?" under Special and General relativity went off...

Sep1605 04:19 PM
hellfire

29 
5,781 
Hi there,
In 3dimensional real linear space, the simplest bases can be taken as the canonical bases
\hat{x} =...

Feb1709 10:25 AM
msumm21

4 
1,497 
how does light slow down considerably when it passes through one? i have always been told that lights speed remains...

Sep204 02:05 AM
Chronos

4 
1,976 
I saw one online material about the boson statistics, it said for boson, it needs the chemical potential to be...

Dec312 09:32 PM
KFC

0 
571 
can we use QM for predict how chemical reaction will end up
or who much energy we must give for a reaction to...

Aug2409 04:34 PM
hagopbul

0 
778 
Does the Compton scattering equation
\lambda '  \lambda = \frac{h}{m_{e} c} (1cos \theta )
work even...

Dec2708 02:26 PM
lightarrow

8 
1,939 
I want to know that ,I have read in many books regarding compton's effect that a photon collides with an electron and...

Jun2014 05:02 AM
Esfand Yar Ali

7 
305 
Suppose that one electron from the end of the universe is emitted to the quantum rectangular barrier potential whose...

Jul511 01:41 AM
Younghun park

5 
1,256 
In Wikipedia this sentence is written about degeneracy;
In physics, two or more different quantum states are said to...

Jul1112 01:15 PM
Amok

3 
503 
Assume there is a two level system, two eigenstates are written as
\psi_1\rangle = \cos\theta 1, g\rangle +...

May909 01:05 PM
deferro

17 
1,536 
In twolevel system, with external field applied, why there is no permant dipole moment? In classical point of view,...

Jun509 07:31 PM
clem

3 
987 
can anyone plzzzzz tell me wether we can write dirac equation in the form of some uncertainty relations,?????????? if...

Apr2709 11:46 AM
g.bashyam

0 
703 
While studying the Dirac Equation, we come across the gamma matrices. Can we consider these matrices as the...

Feb1513 05:09 AM
Bill_K

2 
559 
For a system consists of two particle, says two spins, the wavefunction for that system is a direct product of each...

Oct3008 10:41 PM
KFC

9 
1,798 
I learnt fundamental statistical physics some times ago. But so far I still don't understand how distinguishabilty and...

Feb109 10:37 PM
vanesch

1 
2,500 
As we know that each electron wave function in a periodic potential can be represented in k space by a sum of infinite...

Oct1510 10:30 PM
ntusg

0 
1,712 
Hi every body and how do you do
first sorry of my weak language cuz I'm new physical Researcher at KACST & I'm...

Nov2010 02:41 AM
ArjenDijksman

2 
1,019 
I have some question about Ensemble Average.
The macroscopic variable of some matter is average of microscopic...

May1212 02:37 AM
Nohhoon Lee

0 
624 
On page 237, Weinberg checked eq. (5.7.23) with an example when \mathbf p is along the three direction. Below that...

Jul3112 10:31 PM
diraq

0 
494 
Suppose in one dimension we have a particle in box with the lenght a. If we were to expand it's ground state wave...

Jan1012 03:30 PM
Simon Bridge

1 
660 
I found it is difficult to enumerate all the diagrams and errors easily come out. I like the algebraic approach,...

May2410 03:36 PM
diraq

0 
962 
Hi everybody, I'm new.
I'm approaching to QFT in these months and I have a couple of questions about Feynman rules....

Jul2309 02:06 PM
RedX

2 
1,218 
Hi,
I've just read Feynman's book:'QED:The strange theory of light and matter' and, in order to measure the...

Aug2109 04:30 AM
penguin007

9 
2,047 