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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
36,222 
I am having hard times, trying to find out how the FermiDirac and BoseEinstein distributions give you at a limit the...

Jul112 02:19 PM
Bill_K

1 
441 
When a photon has a wavelength close to the energy needed for an electron jump in an atom, the atom will absorb the...

Jul112 01:08 PM
Hells

2 
650 
Does Pauli's exclusion principle apply to superposition or only collapsed states?
I.e. could a particle be...

Jul112 11:58 AM
Mukilab

7 
793 
A particle in the ground state of a potential well can only gain energy by making a transition to one of the higher...

Jul112 07:39 AM
tom.stoer

5 
911 
Can someone please elaborate these lines:
"Causality applies only to a system which is
left undisturbed. If a...

Jul112 12:52 AM
San K

13 
2,773 
What is the difference between eigenfunction and wave function?
I'm always get confused when i am asked to write...

Jul112 12:38 AM
Simon Bridge

4 
1,049 
Almost everyone is familiar with the sentence "accelerated charges radiate em waves".
Nevertheless, if you are...

Jun3012 08:56 PM
Dickfore

6 
1,022 
Alright. So the Dirac Eq is
(i \gamma^{\mu} \partial_{\mu}  m) \psi = 0
or putting the time part on one side...

Jun3012 06:56 PM
geoduck

7 
1,416 
I have just watched a video by Professor Brian Cox. In it he describes the proposed Higgs field. If it exists, it is...

Jun3012 05:20 PM
Nabeshin

3 
763 
If the Higgs field is responsible for embuing particles with mass, and mass is responsible for gravity, is it possible...

Jun3012 04:13 PM
Parlyne

2 
952 
I am aware that n is the principal quantum number and determines the energy of a specific energy level of an atom. In...

Jun3012 03:20 PM
Einstein Mcfly

4 
1,799 
Do free particles have quantum numbers? What are they?

Jun3012 12:12 PM
xz5x

2 
567 
Hi all! I'm sorry if this question has been already asked in another post...
I'm studying the path integrals...

Jun3012 05:02 AM
Einj

2 
974 
Hi, i can't get the result stated as equation (2.33) in page 22. To be more clear, after the elimination of the...

Jun3012 02:41 AM
dazhuzai8

1 
787 
Hi physicists,
How can two atomicscale particles interact through gravitation (Gm1m2/r^2) or any other force that...

Jun3012 12:00 AM
Simon Bridge

4 
903 
Hi,
could anyone try to explain one thing about the Heisenberg Uncertainty Principle I don't understand?
The...

Jun2912 02:45 PM
Muphrid

10 
1,272 
In the doubleslit experiment, without whichpath information available, the diffraction pattern is usually shown as...

Jun2912 01:00 PM
cygnet1

2 
712 
What are the differences between the probability density function and the radial probability density functions (in...

Jun2912 09:16 AM
CAF123

0 
665 
I'm wondering because the gamma ray photon is smaller yet it has a higher frequency. Is it because the amount of...

Jun2912 07:23 AM
Naty1

17 
9,732 
A quantum particle can tunnel through a barrier and we can describe why this is so by the uncertainty principle....

Jun2912 05:31 AM
ZapperZ

5 
842 
Hello dear readers,
I have a problem. I'm giving a lecture tomorrow on the EPR experiment and Bell's theorem and so...

Jun2912 05:29 AM
Tomer

13 
1,401 
Hello, I'm trying to solve a time independent schrodinger equation with matlab. i wish to write a function whose...

Jun2912 03:14 AM
farzin22

0 
2,003 
What do you think the word "photon" used in textbooks and papers at present mean?
 extended object which, when...

Jun2812 07:35 PM
D H

19 
1,392 
what we mean by uncertainty in energy in quantum tunneling ? it's hard to understand uncertainty principle

Jun2812 03:55 PM
sciboudy

0 
459 
I was studying Rayleigh Scattering.
The theory says that Rayleigh Scattering is approximated to x<<1 where...

Jun2812 12:38 PM
Jano L.

1 
500 
Now please forgive the question, and thank you in advance for your patience....
I am a little confused by the...

Jun2812 10:07 AM
yuiop

12 
1,417 
So I just finished watching a video of the theatrical scientist, Michio Kaku, about teleportion. According to Kaku,...

Jun2812 03:25 AM
Doc Al

4 
611 
Hello,
is there a representation of the process taking place in Xray photoelectron spectroscopy, describing the...

Jun2812 01:26 AM
tom.stoer

3 
534 
Hello everybody,
I just read the following article:...

Jun2712 09:11 PM
mathal

38 
4,306 
From what I've gathered about quantum mechanics, it's based on probability, correct? (Yes, it's true that I know next...

Jun2712 02:59 PM
mathman

1 
391 
I'm a little frustrated with the quantum m lectures I've been watching. I've watched Susskind's, one in India and now...

Jun2712 02:19 PM
Fredrik

30 
3,140 
This is something that I've seen repeated many times, but I'm wondering how accurate it is. I mean, we've got this...

Jun2712 12:02 PM
HJ Farnsworth

164 
13,350 
I think it's time for the annual quantum interpretation poll.
Vote for which interpretation you currently think...

Jun2712 10:44 AM
harrylin

245 
29,785 
I understand the two cases dealt with when we consider the step potential. The two cases being when E>U (i.e the...

Jun2612 06:44 PM
Ken G

7 
1,051 
we know electron revolves around nucleus at nearly (1/100)th of light speed..does this mean electron as very high...

Jun2612 03:56 PM
Darwin123

2 
1,296 
Greetings everyone,
I'm going through Griffiths QM, and just wanted to make sure I understood the roles (where they...

Jun2612 11:44 AM
HJ Farnsworth

11 
1,215 
I was watching a cartoon with my niece.
Most of the time, cartoons have fairly simple things like 1+1=2 and so on....

Jun2612 09:25 AM
Mako Ruu

9 
1,415 
Fermat's principle is also known as the path of least time principle, and it explains why the angle of incidence is...

Jun2612 12:16 AM
icflame

2 
2,431 
How can you tell if two Lie groups are isomorphic to each other?
If you have a set of generators, Ti, then you can...

Jun2512 10:02 PM
fzero

1 
756 
Please forgive such a simple question, but how does a particle 'remember' what direction to travel in from instant to...

Jun2512 08:35 PM
referframe

9 
1,208 