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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
36,183 
I was watching Richard Feynman's lectures on quantum electrodynamics where he concerned the probability of photon to...

Jun314 07:33 PM
UltrafastPED

1 
252 
This oftreferenced picture depicts a simulation of virtual particles popping into and out of existence in the empty...

Jun314 12:07 AM
tom.stoer

2 
320 
It is available for free from this source.
If someone can explain what has really been done here in simple English,...

Jun214 10:57 PM
gelatin

2 
268 
If spherical harmonics are simultaneous eigenfunctions of \hat{L} and \hat{L}_{z}, then that means for a state at...

Jun214 03:53 PM
siddharth5129

2 
228 
I learnt about the E<V(bound) and E>V cases. But what if V=E? Can we at all conclude V=E due to uncertainty...

Jun214 02:17 PM
suvendu

0 
233 
Hey, i hear about quantum teleportation on the news today. They said that they successfully teleported information....

Jun214 12:43 PM
Thinkor

19 
776 
A friend is a quantum chemist. He is in agreement that climate change is bad (he feels the primary problems with CO2...

Jun214 06:27 AM
D H

1 
288 
I have some questions regarding the Heisenberg picture of QM.
1. How does one calculate probabilities for measuring...

Jun214 12:13 AM
atyy

1 
355 
I am going through James Binney's course on Quantum Mechanics. I love all of the little misconceptions he points out...

Jun114 06:30 PM
Matterwave

13 
379 
Hello look at (3.24). Above it, it states "We make the same switch to polar coordinates (x, φ) in the (x, y) plane,...

Jun114 06:14 PM
epislon58

2 
232 
Do individual photons have some attributes which relate to EM wave frequency? In other words, is there any difference...

Jun114 12:28 PM
Nugatory

7 
384 
Quantum Mechanics using Index notation. Is it possible to do it?
I really don't get the Dirac Notation, and...

Jun114 09:00 AM
atyy

105 
2,726 
Is it true that there always exist a unitary matrix that can take a state vector of an arbitrary pure state to another...

Jun114 03:19 AM
tom.stoer

7 
541 
The eigenstates of a hydrogen atom are stationary states with definite values of energy. Now, as I understand it, the...

May3114 05:33 PM
dextercioby

4 
292 
A new type of energy storage described which uses quantum way to store energy.
''Battenice''.
...

May3114 09:08 AM
mfb

1 
514 
I am able calculate the solution for the TISE relating to the interval to the right of a step potential; however, I am...

May3114 02:52 AM
Simon Bridge

27 
1,092 
Is Timespace a literal real thing? or is it an abstract idea?
and what makes physisists so sure that gravity is a...

May3014 07:44 PM
bhobba

3 
432 
I am looking around for some sort of equation regarding optical power dissipation of light (ultraviolet light in...

May3014 12:53 PM
Jano L.

1 
257 
Hello,
I need help understanding how to apply the formula for converting a Lagrangian to an equation of motion in...

May3014 09:14 AM
sloneranger

8 
284 
Hi everybody,
Is it possible to obtain an expression equivalent to fermi golden rule within the framework of Green...

May3014 08:08 AM
Arthas85

0 
230 
I was watching a YouTube video about heisenberg's uncertainty principle and was wondering if it only works for...

May3014 01:45 AM
tom.stoer

11 
360 
I'm looking for the source for the QM interpretation of "shut up and calculate". I thought it was synonymous with the...

May3014 12:34 AM
Demystifier

13 
593 
What happens to ψ in a infinite potential well when the width is suddenly reduced to half its previous value ?
Will...

May2914 10:01 PM
rigetFrog

2 
383 
Am I correct in my understanding that the standard model predicts that there should be more matter than antimatter in...

May2914 10:01 PM
damian081

5 
383 
The smallest amount of energy possible is called quantum of energy and is = hf. But are frequencies also quantized?...

May2914 09:08 PM
DevilsAvocado

19 
910 
As far as I know Feynman was the first who told that if you would put detectors at the double slits the interference...

May2914 03:40 PM
forcefield

7 
369 
Do unobserved particles exchange information with other particles? If not then they are not only unobserved but also...

May2914 01:11 PM
Jilang

7 
329 
Pardon my wording as I do not have a solid background in physics, while pondering The effects of observation on a...

May2914 03:17 AM
DennisN

9 
338 
I have been struggling with one simple question. How can one measure the momentum of a particle within a field without...

May2814 09:16 PM
bhobba

3 
239 
In pseudothermal ghost imaging using a laser beam passing through a rotating ground glass plate, the temporal...

May2814 02:50 PM
nandan

20 
354 
Hi,
I´m not sure if my way of tackling a question, probably it's a trivial problem, but it's important for me to get...

May2814 12:12 AM
bhobba

3 
395 
About the fact that electrons have a determined position only after having been observed/measured, I don't understand...

May2814 12:03 AM
bhobba

5 
490 
So I was reading this http://www.oberlin.edu/physics/dstyer/TeachQM/misconnzz.pdf, a list of common misconceptions...

May2714 11:38 AM
moontiger

5 
403 
Pardon me for my ignorance. This is a question of curiosity.
I look for a concise logical argument as to why the...

May2714 11:02 AM
DrChinese

10 
460 
I know about symmetry and antisymmetry and so on, but a thought that I had never considered just hit me. If we had two...

May2714 01:28 AM
DrDu

3 
296 
Hey everyone.
I have a couple of question regarding wave function collapse.
I can accept that one cannot make...

May2614 10:38 PM
atyy

6 
327 
I'm in the first of 3 courses in quantum mechanics, and we just started chapter 4 of Griffiths. He goes into great...

May2614 10:15 PM
jayqubee

5 
367 
Hi. I am reading a book entitled "AtomPhoton interactions" by Claude CohenTannoudji, et al.
There is a symbol...

May2614 08:50 PM
UltrafastPED

1 
189 
"Locally, the spin density S is an intrinsic (i.e. originindependent) quantity, which is associated with the local...

May2614 06:38 PM
UltrafastPED

2 
283 
Am I right to think that particles cooled asymptotically to 0 K would have wave functions the size of galaxies or even...

May2614 04:59 PM
QuasiParticle

11 
461 