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Feb2313 08:38 AM
ZapperZ

1 
36,429 
In the volume III of R Feynman series which is on Quantum Mechanics , please explain to me the eq.8.43 given on page...

May2708 01:37 PM
Gokul43201

1 
5,328 
There have been countless discussions about the thought experiment about Schrodinger's cat in a box, and how to...

May2708 03:16 PM
StatusX

4 
2,196 
The analytical solution for the wavefunction of a hydrogenic electron with quantum numbers n, l and m has a spherical...

May2708 04:00 PM
StatusX

2 
1,542 
I found this website by a guy named David Sligar: http://www.geocities.com/Area51/Shire/3075/mfield.html
He says: ...

May2808 01:23 AM
gendou2

10 
2,113 
in peskinschroeder and here the amplitude for e^e^+\rightarrow \mu^ \mu^+ is written using feynman rules as...

May2908 10:37 AM
SporadicSmile

1 
1,562 
Can the information content of a causally evolving wave be represented in qubits?

May2908 06:59 PM
Phrak

0 
998 
What is the relationship between the "matter waves" described by de Broglie, the probability amplitude function and...

May3008 07:26 AM
andrewm

1 
2,943 
I have been working through Srednicki this summer to teach myself qft, and all too often I've gotten stuck on a small...

May3008 10:55 AM
ikku

14 
2,789 
Hi,
I'm stuck on "the summit of statistical mechanics" (as Feynman calls it): the definition of the Boltzmann...

May3008 11:14 AM
f95toli

3 
1,100 
What proof is there that Born's probability interpretation of the QM wavefunction is correct? Born published two...

May3008 03:44 PM
peter0302

2 
1,400 
Dear PF,
I have a question about degrees of fridom.
Electron is 1/2 spin particle so it needs 2 component wave ...

May3108 03:54 AM
Ilja

3 
4,035 
Hello All,
As I understand it, the wavefunction Psi(x) can be written as a sum of all the particle's momentum basis...

May3108 12:00 PM
lbrits

3 
10,894 
I have a simple question but can't find the answer:
What happens in the Potential Step (the Schrodinger Equation...

May3108 10:01 PM
CPL.Luke

6 
3,421 
Hi,
I'm a beginner at quantum mechanics and I wonder about this problem. Suppose I have found energy eigenstates of...

Jun108 12:33 PM
comote

3 
1,240 
I've got this question and I'm absolutely clueless, any help will be greatly appreciated:
The nth energy level for...

Jun108 05:11 PM
SuperNomad

4 
2,296 
Hey, iv got a past exam question that im stumped on. The question is "Calculate the equilibrium spacing r for NaCl...

Jun108 06:47 PM
mate1000

0 
3,443 
Years ago, I read a book about quantum mechanics. There is one sentence that gives me a deep impression. The key point...

Jun108 09:55 PM
xylai

0 
1,208 
Is it generally true that the wavepacket of a free particle spreads out as time goes to infinity? It seems like it...

Jun108 11:49 PM
Adeimantus

8 
2,305 
What's this guy saying?
http://www.nature.com/news/2008/080515/full/news.2008.829.html

Jun208 04:37 AM
Demystifier

13 
5,216 
Doesn't this digitize the Universe?
Does 1 Plank Time + 1 Plank Time = 2 Plank time?
Does 1 Plank length + 1...

Jun208 05:54 AM
BayAreaBiker

16 
6,085 
Was the early spontaneous symmetry breaking caused by exponential expansion in the first instant of standard theory?
...

Jun208 07:26 AM
bogie

1 
1,930 
I'm not sure the doubleslit experiment is one such example, maybe I have not understood it yet.
This experiment...

Jun208 03:26 PM
Ulysees

41 
5,371 
I will talk about the quantum chaos.
Quantum chaos comes from the classical chaos. unfortunately, the concept of...

Jun308 07:31 AM
xylai

2 
975 
What are the limitations on the phase velocity of laser light? Is it true to say that the phase velocity of laser...

Jun308 02:37 PM
Andy Resnick

2 
2,406 
I apologize if this is not in the correct section of the forum, but it seems most fitting.
In the context of...

Jun308 04:20 PM
pam

1 
1,669 
I keep hearing that the "many worlds interpretation" is experimentally different than the collapse theories. But I...

Jun308 09:00 PM
Count Iblis

9 
1,994 
I don't understand the first line of equation (5.94) in Peskin and Schroeder (p. 164).
It seems like there is a...

Jun408 06:41 AM
jdstokes

0 
1,513 
I was wondering if i neglect the terms in Hamiltonian except B^{2} how can i solve the Schrodinger Eq.?
I mean, ...

Jun408 07:37 AM
torehan

0 
1,679 
Hello:
There is a well known theorem which asserts that every attractive 1D potential has at least one bound state;...

Jun408 09:31 AM
pam

4 
3,606 
Suppose you have an EPR pair, it's in a state \uparrow>\uparrow>  \downarrow>\downarrow>.
Then you measure one...

Jun408 11:53 AM
reilly

16 
2,816 
Photons are always called 'particles'. But through many experiments (by scientists such as Geoffrey Taylor), it has...

Jun408 12:04 PM
reilly

7 
1,668 
One author states that "the usual Maxwell field is the quantum wave function for a single photon"  see...

Jun408 03:03 PM
jostpuur

7 
2,963 
Is it true that particles behave like waves when there is no observer but behave like particles when there is an...

Jun508 05:06 AM
NYSportsguy

28 
5,124 
My understanding is that Hawking's radiation is a theory used to explain how blackhole's conserve energy. For...

Jun508 09:43 AM
2Tesla

18 
3,727 
I know this question seems very simple which is why its bugging me so much:
Why is the ground state energy not zero?...

Jun508 10:14 AM
physmile

3 
2,129 
Hi all,
could someone give me a quick answer on the exact conditions for the hamiltonian to be non degenerate, i.e....

Jun608 01:48 AM
omg!

16 
1,665 
I just read an article in Scientific American by Sean Carroll, called something like Does Time Run Backward in Other...

Jun608 02:26 PM
no_math_plz

14 
2,555 
Ten years ago, I posted a long rambling post concluding with a thoughtexperiment on Usenet, and got no useful...

Jun708 01:02 AM
dkv

69 
6,696 
When considering a simple hydrogen atom, which essentially is an electron moving in a spherical electric field, you...

Jun708 05:21 AM
Zacku

1 
1,917 
Does anyone know, when an electron in an atom is exited by absorbing a photon, how long does it take for the electron...

Jun708 05:40 AM
f95toli

1 
2,729 