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Feb2313 08:38 AM
ZapperZ

1 
36,451 
I am currently working on trying to understand some of the details in quantum physics.
So far, Schrodinger's...

Jul2212 07:17 AM
Rap

6 
1,284 
Hi all,
A friend and I are working through Peskin and Schroeder, and we're both stumped with only the fourth...

Jul2112 02:57 PM
ianhoolihan

12 
1,867 
Say we have a linear accelerator, that accelerates particles with 1 TeV along direction x. That means we know that the...

Jul2112 02:28 PM
Simon Bridge

1 
572 
When you combine two light beams with a halfsilvered mirror, do you get a mixture or a superposition?

Jul2112 01:59 PM
jimgraber

2 
493 
If you have I=∫∫dxdy x∇y δ(xy)] f(x)g(y)
where ∇x is the derivative with respect to x (and similarly for y), then...

Jul2112 12:31 PM
Hurkyl

1 
970 
Hello,
I am trying to reproduce Bell's calculation for the expectation value of paired spin measurements on...

Jul2112 11:47 AM
Adam Lewis

1 
955 
"Quantum measurement predictions are consistent with relativity for macroscopic observations, but there is no...

Jul2112 10:37 AM
nikman

0 
674 
In all my reading on the dual slit experiment the idea that the particle went through a single slit is never even...

Jul2012 02:55 PM
DrChinese

17 
1,693 
So i've been trying to understand this equation for a long time, about half a year  I don't know someone who could...

Jul2012 06:27 AM
mikeph

14 
1,561 
Hi.
I have read some QM and am trying to use it to understand why the noble gas configuration is the most desirable...

Jul1912 06:02 PM
Darwin123

2 
971 
So, in QM making a measurement collapses the state into an eigenstate of that observable. Thus, if the system is...

Jul1912 03:07 PM
LastOneStanding

9 
1,181 
I was wondering why is the nucleus willing to confine itself in one place while the electrons are free to appear...

Jul1912 10:26 AM
PhilDSP

3 
889 
Why do we consider evolution of a wave function and why is the evolution parameter taken as time, in QM.
Look at a...

Jul1912 10:14 AM
vanhees71

2 
707 
Hi,
can anyone explain me why (mathematically) the braid group is infinte? I guess it's infinite because you can do...

Jul1912 10:01 AM
martinbn

1 
552 
(is this correct … ?)
electrons "orbiting" a single atom obey the Schrodinger equation, whose solutions are linear...

Jul1912 07:58 AM
tinytim

4 
1,585 
So De Sitter Space has a constant scalar curvature in the absence of energy or mass where positive curvature...

Jul1912 01:47 AM
tom.stoer

1 
549 
I have a question about a specific passage in Hill's book on statistical thermodynamics. I have decided to teach...

Jul1812 07:31 PM
unchained1978

9 
921 
Hi,
Quick question regarding raising and lowering operators.
Sakurai (on pg 23 of Modern QM), gives the spin 1/2...

Jul1812 07:26 PM
Chopin

9 
1,318 
Can you calculate the frequency at which a bond vibrates when you know what frequencies of EM radiation it absorbs?...

Jul1812 06:09 PM
Simon Bridge

1 
1,146 
Over which interval do the wave functions of a harmonic oscillator form a complete and orthogonal system? Is it...

Jul1812 04:06 PM
Matterwave

1 
434 
Hello.
I was trying to find out the propagator for the inverted SHO (something like tachyon oscilltor) and turns...

Jul1812 07:33 AM
FedEx

0 
420 
Hello everybody,
I try to understand Cherenkov radiation from a quantal point of view. I searched for research...

Jul1812 05:20 AM
Syrius

0 
449 
So, we probably all know by now the Schrodinger's cat thought experiment. A cat is in a box with a small amount of...

Jul1712 04:43 PM
soothsayer

5 
1,091 
Hi all, this is a question about Green's functions (sometimes called corrolation functions), used in the LSZ reduction...

Jul1712 02:48 PM
alemsalem

2 
660 
Hi!
I'm currently rereading Griffiths introductory QM book and plan to do most of the exercises. I got stuck on...

Jul1712 12:48 PM
soothsayer

1 
965 
I know that the shape of s orbital is sphere, p orbital is dumbbell shaped and d orbital is like a doughnut but why do...

Jul1712 05:47 AM
ZapperZ

15 
2,116 
I got a copy of QFT demystified and on pg. 89 he says he can write \gamma_{\nu} \gamma^{\mu} = g_{\nu \sigma}...

Jul1612 09:42 PM
silence11

7 
748 
What does the expectation and deviation of an operator mean??
The way I understood it was every observable has a...

Jul1612 04:36 PM
mikeph

5 
777 
I started off with Zettilis Quantum Mechanics .... after being half way through D.Griffiths ..... Now Zettilis...

Jul1612 03:12 PM
micromass

4 
1,099 
I may have figured out a way to do that, unless there is some fundamental principle I am not currently aware of. I...

Jul1612 11:30 AM
Duplex

23 
3,496 
can coherence be restored (after decoherence)?
let's look at single particle (interference) in a double slit...

Jul1612 11:29 AM
f95toli

9 
772 
Hi,
Lately I've been reading up on quantum entanglement, Bell's inequality, and EPR experiments. My question is...

Jul1612 11:09 AM
rkn

22 
1,965 
I'm curious as to whether or not there is a connection to be drawn between the phenomenon of wave function collapse...

Jul1612 08:50 AM
DrChinese

5 
1,027 
Hi,
There are, for example, lists of spherical tensor operators for l=\text{integer} steps, e.g. l=0,1,2,....
...

Jul1512 01:13 PM
jfy4

4 
795 
Once Ive asked here why you physicist use Gauge theories with such confidence and the overall answer was "because it...

Jul1512 09:33 AM
tom.stoer

5 
1,681 
Recently i am reading A.Zee's Quantum Field Theory in a Nutshell 2nd Edition. there is a equation that i can not...

Jul1512 04:53 AM
tom.stoer

8 
964 
Hello people,
i am an undergraduate student on computer science (so i don't have a strong background in physics)...

Jul1412 08:43 AM
fedonman

4 
717 
I was reading an elementary treatment of the photoelectric effect and it says that the energy of a photon is related...

Jul1312 09:13 PM
Darwin123

19 
2,305 
I'm having trouble seeing how an operator can be written in matrix representation.
In Sakurai, for an operator X,...

Jul1312 01:53 PM
Fredrik

2 
754 
I was flipping through Kitaev's quantum computing book today and noticed something really strange. I thought it might...

Jul1312 10:34 AM
Physics Monkey

3 
650 