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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
30,378 
Hello, I need a help for making a short visual presentation of superposition and wavefunction collapse. It will be a...

May212 04:30 PM
kyoto

0 
686 
I'm doing an exercise regarding the spinorbit operator and the Dirac equation/particles, and I'm having trouble...

May212 12:57 PM
Bill_K

1 
651 
In principle, what is the absolute simplest arrangement to cause decoherence? In other words what constitutes a...

May212 10:05 AM
TrickyDicky

9 
1,148 
HI,
I am looking for the ''Physics of Quantum electronics vol.8 chap.5'' I could no where find this book /journal...

May212 10:04 AM
marygreen

1 
746 
How to sum in phase space with discrete energy? We have a question that needs to calculate Edp^3. If energy E is a...

May212 08:12 AM
mings6

0 
307 
One of the more common ways of showing that a Hamiltonian with periodic potential commutes with the translation...

May212 04:03 AM
Hurkyl

2 
1,237 
Greetings!
I have a question about the current interpretation of the laws of nature which, according to what I...

May112 11:40 PM
johnny55

3 
3,740 
Well I'm trying to understand the doubleslit experiment (and quantum mechanics), so could you tell me if this is...

May112 05:27 PM
ace frehley

2 
760 
Hi!
In Weinberg's book "The quantum theory of fields", chapter2, it states that the transformation
of a massive...

May112 03:18 PM
dextercioby

1 
678 
Hey
I been reading about an experiment that took place involving two metals plates in a vacuum, of which they are...

May112 02:12 PM
Mr_Physicist

3 
842 
Please teach me this:
Despite perfect theories(e.g quantum theory) we never have a absolutely fitted between...

May112 01:53 PM
f95toli

7 
1,166 
Wave functions and their exp(ipx) are base of quantum mechanics and QFT. But how to derive them the most simply that...

May112 01:51 PM
jbcool

6 
2,335 
Entangled particles are used in various experiments for example:
DCQE (delayed choice quantum eraser)
Bells tests...

May112 10:48 AM
San K

2 
745 
I came across this statement from James Hartle on Stephen Hawking's website,
http://www.hawking.org.uk/
and...

May112 07:54 AM
Naty1

3 
2,095 
Is the following the definition of wedge product in tensor notation?
Let A \equiv A_i be a matrix one form. Then...

May112 03:47 AM
haushofer

1 
1,064 
Hi,
I am trying to figure out the following integral. I have two normalized 1D harmonic osccilator wave functions...

May112 01:17 AM
TomDance

5 
959 
Quite often one can see descriptions saying that the coherence time of single photons corresponds to the length of the...

Apr3012 10:26 PM
Bob S

5 
1,661 
I was wondering about a system, specifically quantum, though classical solutions are still welcome, which was...

Apr3012 05:22 PM
jbcool

0 
588 
Hello...sorry about the vague nature of the question..but I am trying to learn in an 'economical' sort of way. That is...

Apr3012 12:25 PM
Mark M

1 
624 
Hi, i have a few questions about these two processes. Now, im only 16 years old, in my last year of school, so im not...

Apr3012 11:37 AM
Bob S

3 
907 
Hi there. I found a paper ( http://users.ox.ac.uk/~lina0174/born.pdf ) which states that has derived the Born Rule....

Apr3012 10:14 AM
the_pulp

0 
587 
I have a homework problem which asks me to compute the second and third excited states of the harmonic oscillator. The...

Apr3012 06:24 AM
kloptok

8 
2,089 
Hi,
can anyone explain to me, how the FeynmanKac formula is used to obtain the following expression for the...

Apr3012 04:10 AM
csopi

0 
847 
I want to know if a quantum computing model exists where you can prepare two different states on n qubits and...

Apr3012 01:41 AM
IttyBittyBit

1 
715 
Please teach me this:
We know that orbit angular momentum is the product of coordinate operator vector and momentum...

Apr2912 11:27 PM
ndung200790

5 
1,535 
I've been studying the path integral approach to QM on my own, and trying to draw some analogies between the partition...

Apr2912 04:28 PM
unchained1978

0 
635 
Hi all,
I've recently been reading about the Unruh effect, and there are a few things that I'm not very clear on:
...

Apr2912 03:33 PM
sheaf

8 
1,399 
My question concerns the 1/2 factor in the exponential of Eq. (3.49) of Peskin and Schroeder.
This equation...

Apr2912 02:17 PM
jmlaniel

2 
880 
In nuclear physics, when two nucleons (e.g. a proton and neutron) fuse together, they release binding energy.
There...

Apr2912 12:59 PM
Nugatory

1 
1,045 
I tried to solve a time independent schroedinger equation with a finite potential well today by solving it in 3...

Apr2912 09:52 AM
ShamelessGit

2 
457 
Special relativity gives that time for a (traveler on) photon do not run. It also gives that every moving elementary...

Apr2912 08:20 AM
Demystifier

6 
921 
Hi there, I have a short thought that I want to share with all of you and see if there has been something written...

Apr2912 06:41 AM
Jano L.

1 
554 
Hello,
I have a question about Schrodinger's equation and the finite well. It isn't so much as a math question but...

Apr2912 05:36 AM
ShamelessGit

2 
817 
Consider classical electron theory. Distinguish between the mechanical, electromagnetic, and observed electron mass....

Apr2912 05:07 AM
Jano L.

1 
668 
the hotter an object is, the bigger it is. So, what is happening with atoms? Do they get bigger or are they any...

Apr2912 02:32 AM
Marshallaw4

3 
629 
Since the issue of deriving the Born rule comes up from time to time in the forum and I'm always a little mystified by...

Apr2812 10:05 PM
strangerep

10 
1,235 
When we use polarisation rotators to measure certain polarisations for entangled photons, the photon usually meets a...

Apr2812 03:23 PM
StevieTNZ

2 
711 
Suppose it is known that a photon has diagonal polarisation (e.g. it has just passed through a diagonal slit), then...

Apr2812 08:44 AM
sweet springs

2 
721 
I'm currently in the midst of a QED course which presupposes a lot of relativistic QM, which I never saw in depth. I...

Apr2712 03:25 PM
sam guns

0 
670 
The following comes from Landau's Statistical Physics, chapter 32.
Using a Hamiltonian
\hat{H} = \hat{H}_0 +...

Apr2712 09:48 AM
mSSM

2 
715 