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Feb2313 08:38 AM
ZapperZ

1 
36,209 
Hi
I need to find the generators of the Poincare group in the representation of a clasical scalar field.
Every...

Jul1108 12:54 PM
udaraabey

2 
2,039 
The classic physics problem example of symmetry breaking is a pencil sitting directly on its tip (pointed down), but...

Jul1108 09:34 AM
peter0302

5 
1,735 
1.in the attached file see the fig 8.5 What is the the physical reason,for which ahe amplitude of the wave function...

Jul1108 03:29 AM
jtbell

2 
961 
I tried to make a doubleslit experiment, but I got some difficulttoexplain results.
I cut a piece of opaque...

Jul1008 03:52 PM
Mr_Wilson914

5 
3,558 
Is there a way bras and kets can be understood in terms of vectors and tensors and coordinate bases?
I'm fairly...

Jul908 11:30 PM
Phrak

154 
11,397 
I have a question regarding this post in the FAQ's:
My question is, to what extent is the above applicable to...

Jul908 06:18 PM
lightarrow

8 
2,984 
Hi,
how i could simulate light not yet polarized with jones formalism?

Jul908 02:25 PM
madmike159

6 
1,636 
1. Is thermal noise truly random?
By truly random I mean can you not predict the next value even if you knew...

Jul908 01:32 PM
DrChinese

4 
4,030 
suppose a laser beam reflects off a mirror moving at relativistic speed. the frequency of the reflected beam will be...

Jul908 12:59 PM
granpa

0 
863 
It seems to me that in the quantization of a classical field, one first takes the fourier transform of the field to...

Jul908 04:28 AM
Demystifier

6 
1,347 
Parity is a special property in Quantum mechanics.
I don't know whether it relates to group thery?
Is it O(2),...

Jul908 04:25 AM
xylai

2 
840 
According to the Bloch's theorem, the solutions of SE in a periodic potential may be written as superpositions of...

Jul908 01:08 AM
jostpuur

1 
1,350 
To find the expected value of Q(x,p) we evaluate <\psiQ(x,i\hbar \frac{\partial }{\partial x})\psi>. But what do...

Jul808 04:58 PM
clem

11 
1,400 
I am reading The Elegant Universe by Brian Greene. It is really wonderful, however, I am confused by a section about...

Jul808 04:52 PM
Fredrik

11 
4,277 
Hello !!!
I have a question that breaks the head to me, jejeje
In the process of photoemission, the total cross...

Jul808 03:55 PM
Diracn

0 
1,255 
A very noobish physics question: Has it been experimentally verified, that individual photons get refracted, for...

Jul808 01:45 PM
Ciokko

2 
1,180 
hi
i just wanted to ask if anyone could help me understand this principle i have read around and still seem to be...

Jul708 11:39 PM
DopplerDog

3 
2,039 
I'm stuck on a problem. Given a Hamiltonian
H_{ab} = cP_j(\alpha^{j})_{ab} + mc^{2} (\beta)_{ab}
then
...

Jul708 09:18 PM
waht

2 
1,727 
EDIT: Sorry... I have to use perturbation theory. My mistake.
Hey... I have a quick question. I have to calculate...

Jul708 03:55 PM
scorpion990

2 
2,467 
Hi,
I'm a network security student who is implementing a protocol on quantum cryptography (focus on EPR photons). I...

Jul708 04:56 AM
gandalf215

0 
1,247 
# Hi guys! One question is troubling me a lot. It is know fact that a hollow metallic enclosure with a small hole is a...

Jul608 09:22 PM
Andy Resnick

2 
1,618 
A massless particle situated in a 1D infinite square well with momentum only in the direction of quantum confinement...

Jul608 05:02 PM
per.sundqvist

27 
3,309 
When I began to fully understand entanglement of quantum systems and what this implies, I was in particular excited by...

Jul608 04:54 PM
yuiop

10 
10,626 
In classical mechanics the Lagrangian depends only on time, position, and velocity. It is not allowed to depend on...

Jul608 03:22 AM
per.sundqvist

2 
1,201 
I was reading the book "New Theories of Everything" and I came across the term "random symmetry breakings" Let me...

Jul608 02:07 AM
djeitnstine

2 
1,186 
Dirac's theory of the electron predicted that there were identical particles of equal mass but of negative energy.
...

Jul508 07:26 PM
kahoomann

0 
1,231 
This might be a silly question, but do protons and neutrons have a wave function that they can be described by?

Jul508 12:56 PM
Crosson

3 
2,399 
Hi there
I have a question regarding the attom
Not saying its possible but if it was what would happen to matter if...

Jul508 12:40 PM
Xezlec

2 
865 
I'm sure you've all heard of Schrodinger's thought experiment regarding Quantum Mechanics.
The question is: does...

Jul508 10:09 AM
muppet

24 
2,959 
When Dirac solved his equation for electron, he found out there are negative energy states.
My question is why...

Jul508 09:23 AM
ismaili

1 
1,558 
I read somewhere that at small atomic levels (quantum levels) the electric force is some 100,000 stronger than the...

Jul408 09:15 PM
Mentz114

12 
2,198 
What does a particle in a potential well means?
What is the physical interpretation of it?
Could any one anser this...

Jul408 01:01 PM
Domenicaccio

2 
2,099 
I know they must use some sort of wave equation to calculate the exact orbitals of an atom, but I'm interested how...

Jul408 10:19 AM
arunma

5 
7,013 
I have a few questions.
Why is it that detection of a virtual particle would mean that it cannot be virtual? What...

Jul408 04:39 AM
nughret

6 
1,528 
hi all, i'm new here :shy:
i'm italian, so i apologize for my english
i never studied quantum physics (i only...

Jul308 07:36 PM
Mentz114

19 
9,412 
Hey folks,
I'm reading Zee 'Introduction to QFT' and have a quick question on some terminology.
On page 10 he...

Jul308 03:21 PM
Hans de Vries

17 
2,493 
Hello,
After reading a little about Planck's constant, I'm a bit confused. The constant is measured in Joules *...

Jul308 11:55 AM
nuby

13 
4,464 
I don't really understand how we observe spectral lines of a particular element and why they are there? Can anyone...

Jul308 07:46 AM
f95toli

5 
2,538 
Fermi energy:
E_f =\frac{\hbar^2 \pi^2}{2m L^2} n_f^2
The number of states with energy less than E_f is equal to...

Jul208 09:43 AM
malawi_glenn

15 
1,442 
In QM we require that an operator acting on a state vector gives the corresponding observable multiplied by the...

Jul208 08:40 AM
Bobhawke

2 
896 