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Feb2313 08:38 AM
ZapperZ

1 
35,256 
From what I've learned in physics, electrons falling from higher energy levels to a lower energy level emits an photon...

Mar2613 11:24 AM
AkInfinity

7 
1,084 
I've been reading a lot of solar cell articles, especially those having to do with nanophotonics. There is a term that...

Mar2613 08:03 AM
Bill_K

2 
590 
I asked my professor if we could define time as an operator and he said no.
I've read on the web that time isn't an...

Mar2613 03:14 AM
Demystifier

30 
2,568 
Hello gang, I wanted to get these lectures to you earlier but I was "temporarily indisposed," or should I say,...

Mar2613 02:07 AM
dx

1 
640 
Someone asked me which math topics to study in order to learn quantum information theory. I thought it was a good...

Mar2613 01:54 AM
atyy

4 
1,114 
I read an article I found on the internet the other day about some Chinese scientists who have set a new speed record...

Mar2613 12:21 AM
Cthugha

3 
551 
"Mysticism in Quantum Mechanics": the forgotten controversy by Juan Miguel Marin, Harvard, Eur. J. Phys. 30 (2009) 807...

Mar2513 11:03 AM
DrChinese

4 
822 
Hi guys, this is my first time posting, I'm studying physics at uni, in my third year and things are getting a bit...

Mar2513 10:52 AM
Cazicami

2 
484 
If light is quantized, and is given out in packets, why are the EM wave spectrum and the black body spectrum...

Mar2513 10:04 AM
cabrera

16 
4,706 
Hello!
I'm currently reading Ryder  Quantum Field Theory and am a bit confused about his discussion on the...

Mar2513 09:14 AM
Kontilera

2 
778 
the wave functions of individual particles can be added together to create a wave function for for system, that means...

Mar2513 08:20 AM
ashutoshsharma

3 
657 
Is there a discussion on this board of the possibility that consciousness is the missing link in a true unified field...

Mar2513 08:05 AM
ZapperZ

1 
574 
Hi there!
I understand the tendancy of physicists to stick to the math, and the logic itself, and to often avoid...

Mar2513 07:30 AM
StevenGuy

12 
684 
Hi,
Any graphs that show how these two relate? (Thomson at low energy with KNishina?)
Any illustration will do,...

Mar2513 06:06 AM
M. next

0 
377 
Lets say I have a spin1/2 particle that is about to enter a nonconstant B field.
the spin 1/2 particle has a state...

Mar2513 04:49 AM
mfb

1 
532 
If I could get anything and everything you guys know about light being quantum or the behavior of light with time. I...

Mar2413 09:04 PM
fluidistic

4 
580 
So for my AS specification I need to know how to use the debroile wavelength equation which is fair enough and easy. ...

Mar2413 05:44 PM
DrClaude

6 
1,022 
I am reading my textbook of QFT (Maggiore, Modern Introduction in QFT), and there is this statement:
"If T^a_R is...

Mar2413 12:03 PM
Bill_K

10 
1,037 
If virtual particles are popping into and out of existence all the time, why aren'twe? Why aren't the particles that...

Mar2413 11:26 AM
LayMuon

3 
612 
I'm new to QM, but I've had a linear algebra course before. However I've never dealt with vector spaces having...

Mar2413 04:59 AM
Jano L.

10 
1,739 
This result will shortly revolutionize physics. This short paper breaks the barrier which has kept time as a Cnumber...

Mar2413 02:55 AM
strangerep

4 
338 
You can watch it on YouTube at:
http://youtu.be/iVpXrbZ4bnU
It uses high definition 3D graphics to explain the...

Mar2313 04:05 PM
Eugene381

0 
725 
(1,a^2,a^2,a^2)) from the action; \mathcal{S}_{D} = \int d^4 x \det(e^{\alpha}_{\mu}) \left
I can show that,...

Mar2313 01:19 PM
pleasehelpmeno

6 
807 
In quantum mechanics what quantities are actually measured? Measurements of voltage and current are macroscopic...

Mar2313 08:00 AM
friend

4 
729 
Hi, I've been curious about his subject for quite a while now, and I figure I need to ask here in these forums to get...

Mar2213 06:34 PM
jlefevre76

0 
562 
Hi there,
This should be very simple...
If I have a state <1AB2> where A and B are Hermitian operators, can I...

Mar2213 05:51 PM
raymo39

6 
699 
So I definitely believe that the continuity of the Dirac equation holds, there is one thing that annoys me, which is...

Mar2213 10:14 AM
andrien

1 
581 
Is there some mathematical prove that for ground state in QM problems wave function doesn't have any zeros?

Mar2213 09:04 AM
DrDu

15 
959 
Do you believe that "conscious" observation has anything to do with "collapsing" superimposed quantum states, or do...

Mar2213 05:51 AM
HomogenousCow

7 
984 
I was talking with a friend earlier today about the idea that at absolute zero, particles essentially stop moving. I...

Mar2213 03:26 AM
DrDu

5 
2,027 
Hi,
I've seen quite a few textbooks and lectures start by saying something like "to solve a quantum system of N...

Mar2213 03:07 AM
cgk

8 
1,179 
Hello, all,
I have a question about the wave functions of H atom: for p orbital, wave functions from the...

Mar2213 03:03 AM
DrDu

11 
1,097 
ψ(x,t)2 is the probability density.
Probabilities are dimensionless.
What would the SI units of ψ(x,t) be,...

Mar2113 06:09 PM
Jazzdude

5 
991 
Let's say if general relativity is wrong. What is then the problem of unifying gravity with quantum mechanics? Is...

Mar2113 03:56 PM
Fredrik

16 
1,389 
Can anyone give me a brief introduction?
Thanks!

Mar2113 03:12 PM
fzero

1 
358 
How should I think about symmetry currents?... in particular, when there are no fields to "carry the charge", eg in a...

Mar2113 01:17 PM
Tarti

3 
591 
This may be a basic question, but it's something I'm having a hard time understanding. The Wikipedia article I am...

Mar2113 12:44 PM
Bill_K

18 
1,340 
In problem of infinite potential well particle can't be in a region where ##V=\infty##. How we know that in case of...

Mar2113 09:25 AM
mfb

9 
884 
In a Griffith's book (page 1516) an author derives a momentum operator. In the derivation he states that he used a...

Mar2113 05:07 AM
DimReg

10 
1,372 
I'm currently working on a paper dealing with aspects of FranckHertz experiment, and encountered some puzzling...

Mar2113 03:14 AM
bentzy

8 
612 