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If you are seeking help with a...

Feb2313 08:38 AM
ZapperZ

1 
30,359 
Hello, I've been trying to define <p2> in terms of <x2>, much the same way that you can write <p> = m d<x>/dt, because...

Feb1814 10:28 AM
Simon Bridge

1 
274 
Hello everyone, I'd like to start off by expressing my appreciation for the existence of this forum to begin with. I...

Feb1814 05:52 AM
bhobba

6 
308 
given two system is entangled, A>=(0_{A}>+1_{A}>)/√2, B>=(0_B{}>+1_B{}>)/√2. entangle state AB>what is the...

Feb1814 03:03 AM
bhobba

2 
280 
The uncertainty in this principle is talking about uncertainty of measurement or particle itself?

Feb1814 01:49 AM
Maui

14 
397 
Quantum mechanics says that physical observables are selfadjoint operators. Is this correspondence a bijection, ie...

Feb1714 08:18 PM
bhobba

12 
807 
Question about quantum spin:
So for the Schrodinger equation, the angular momentum of a wavepacket, whether it is...

Feb1714 07:57 PM
WannabeNewton

3 
378 
hello
How to you rigorously express the orthonormality of a complete set of eigenvectors (q\rangle)_q of the...

Feb1714 07:47 PM
strangerep

21 
1,180 
I am reading Field Quantization by Greiner and Rienhardt and I am trying to prove that
i\hbar \frac{d\hat{b_k}}{dt}...

Feb1714 07:02 PM
Henriamaa

0 
213 
Hi,
I'd like to argue Heisenberg doesn't apply to a collapsed wave...
I always interpretted the Heisenberg...

Feb1714 05:21 PM
atyy

32 
1,137 
What ever happened with QFT? Heard so much about it years ago now only once in a while will a past Nobel laureate...

Feb1714 02:27 PM
ZapperZ

22 
1,171 
The electromagnetic spectrum contains wavelengths that are on the scale of macroscopic objects. What I'm not sure...

Feb1714 01:01 PM
phy_infinite

15 
548 
I just listened to a lecture on this, and I'm not sure I quite get the point.
What the lecturer did was examine...

Feb1714 10:08 AM
vanhees71

2 
362 
Consider our universe but with only two particles, say two protons. Inevitably they would orbit mutually about one...

Feb1614 06:12 PM
DaleSpam

9 
453 
Hi PF members. I have got a little worry
I am familiar with the Zeeman term that always appears in the Hamiltonian of...

Feb1514 09:17 AM
Bill_K

5 
428 
I came up with the following idea of a device:
We have a short circuited type2 (to allow more current)...

Feb1514 03:07 AM
goran d

0 
222 
If an electron gets excited from K to L shell, it will actually finish in the 2p subshell and then deexcite to 2s and...

Feb1414 11:38 AM
Chemist@

7 
346 
How is the wavefunction of an electron determined? I've seen images which show that it looks like this :...

Feb1414 10:07 AM
Nugatory

5 
395 
Hello,
I have been studying Introduction to Quantum Mechanics by Griffith and in a section he solves the...

Feb1414 06:50 AM
ChrisVer

5 
401 
After time t, the probability of monochromatic absorption of the ground state 1> to the energy state n> is given by:...

Feb1314 11:06 PM
ChrisVer

10 
405 
Hey guys,
I study biophysics, so maybe this is a sophomoric question. I've done a cursory, albeit fruitless search...

Feb1314 03:00 PM
Jilang

20 
851 
hi guys, i just have a quick question concerning the Copenhagen interpretation of things.
say there is a star, very...

Feb1314 02:23 PM
DaleSpam

108 
4,512 
Hi,
I know this is old news at this stage, but I was watching his public lecture on quantum mechanics, and he says...

Feb1314 02:23 PM
DaleSpam

82 
2,474 
Hi,
this probably has been answered somewhere here already, but I was unable to find it.
Could someone explain how...

Feb1314 05:35 AM
xortdsc

3 
376 
I know that transistors work using QM, but I dont know how, can someone explain this to me?

Feb1214 10:23 PM
Simon Bridge

5 
368 
Hello. This is my first post here. I am an undergrad student and my first experience with quantum mechanics isn't...

Feb1214 04:18 PM
petera88

1 
251 
I have the following question for anyone who can help:
Suppose in Dirak notation i have the following state:
/ψ> =...

Feb1214 03:21 PM
dauto

1 
247 
Hey guys! First time posting on this site. Been reading for quite a while and really loving it! :thumbs:!
I'm a...

Feb1214 01:09 AM
Khashishi

3 
360 
The spin angular momentum of a spin 1/2 particle is given by S = √(s(s+1))ℏ. If s =1/2,
S= ((√3)/2)ℏ
So, if s=1...

Feb1114 02:06 PM
liometopum

4 
345 
1. A photon that emerges when an electron jumps one orbital down  will have a fixed energy
...i.e. the different...

Feb1114 12:34 PM
San K

7 
485 
Once a wavefunction has collapsed, can the system change to a new state if we disturb the system?
For example, if...

Feb1114 07:19 AM
atyy

1 
311 
Hello Everyone,
I'm brand new to the forum as a poster, although I have been quietly reading the very interesting...

Feb1014 12:24 PM
mfb

3 
1,788 
As a physics student, I was taught that refraction happens because when light approaches a material with a refraction...

Feb1014 05:46 AM
Bill_K

2 
288 
I think that Wick theorem permits us to contract boson field operator with fermion field operator(?).Because the...

Feb1014 01:43 AM
ndung200790

1 
247 
Do atoms "generally" exhibit superposition when not isolated from the enviorment?I know that electrons and photons do...

Feb914 09:24 PM
bhobba

20 
705 
http://farside.ph.utexas.edu/teaching/qm/lectures/node53.html
So I was reading this and I don't understand how he...

Feb914 07:31 PM
Avodyne

2 
449 
Hi everyone,
today I had a thought coming across my mind when I woke up, and I think it might be an explanation for...

Feb914 05:07 PM
DaleSpam

92 
4,604 
Suppose that operators A and B have complete sets of eigenfunctions, = 0, and Ψ is an eigenfunction of A with the...

Feb914 04:31 PM
dextercioby

3 
309 
we're learning about some of the properties of the steady state wave functions confined in an infinite well. one of...

Feb914 10:49 AM
WannabeNewton

3 
326 
Hi,
as I understand it, in hydrogen with its electron in the porbital there is a charge polarization (negative in...

Feb914 06:51 AM
xortdsc

2 
281 
i was just reading the following article and had an interesting thought;...

Feb814 10:58 PM
bhobba

3 
342 