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Feb2313 08:38 AM
ZapperZ

1 
30,328 
I have a question in Srednicki's book regarding path integrals, but first I'll set it up so that no familiarity of the...

Aug1909 01:49 AM
RedX

2 
824 
For the free photonfield:
Z=exp(\frac{i}{2} \int d^4x \int d^4y J^\mu(x)\Delta_{\mu \nu}} (xy) J^\nu(y))
...

Aug2809 01:29 AM
Ben Niehoff

3 
693 
A Dirac field can be written as two Weyl fields stacked on top of each other: \Psi= \left( \begin{array}{cc} \psi \\...

Oct2209 11:04 PM
RedX

0 
738 
Both (i d/dx) and (i d/dx ) are Hermitian. For some reason (i d/dx ) is chosen to be the momentum operator, and the...

Oct2409 12:08 AM
Ben Niehoff

1 
632 
In the expression ln(s^2i\epsilon) , s^2 and \epsilon are positive (this expression can result from for example a...

Nov1009 10:35 AM
RedX

2 
612 
How does one begin to prove the renormalizability of a theory? Powercounting can give you a big clue about...

Nov1009 10:28 AM
RedX

0 
572 
I read somewhere that the irreducible representations of Lie groups were countable. But what about translations? Isn't...

Dec1209 09:28 PM
RedX

11 
1,313 
When solving Schrodinger's eqn. one comes across the expression:
\frac{d^2 \psi}{dx^2}=(VE)\psi
where the mass...

Dec1709 04:18 PM
RedX

0 
811 
I was posting on another thread and it got me wondering: how come a photon is absorbed in the photoelectric effect but...

Aug1409 02:02 AM
vin300

6 
1,284 
I've never really understood how electron taking the form of a standing wave in the orbit of a nucleus can have...

Aug1909 01:50 PM
Naty1

27 
2,353 
I'm really confused on this concept. Why is gravity considered a fictitious force and is it true that this concept is...

Jul2310 06:11 PM
Glen Bartusch

3 
1,304 
I began my physics study about one year ago and learned all of classical mechanics in that year; but I am now studying...

Jul3108 03:23 PM
humanino

4 
1,768 
I've been shopping economically for textbooks, and I was wondering how much difference there is between the 1994 and...

Aug2508 05:54 PM
Reedeegi

0 
1,620 
After finding and reading Geroch's notes on Quantum Mechanics formulated within Differential Geometry, I was wondering...

Feb1510 08:24 PM
humanino

3 
916 
I'm having trouble relating the classical (Maxwell) model for electromagnetic radiation to the quantum mechanical...

Nov3008 01:39 PM
clem

1 
1,323 
A few of the formulas that I have seen for calculating Planck's constant involve, amoung other things, dividing by the...

Jan409 10:53 AM
jtbell

5 
3,079 
In QM, the energy of a particle with a nonzero rest mass is Planck's constant times the frequency. How does the...

Jan1009 12:00 AM
daschaich

3 
1,721 
Does a charged particle at rest (m0>0) have more total energy than an uncharged particle with the same rest mass at...

Feb1609 01:06 PM
Bob_for_short

7 
1,470 
The Uncertainty Principle is largely mathematical. For any two probability densities, if one is the Fourier...

Feb2209 11:03 AM
nicksauce

2 
2,660 
In the EnergyMomentum 4Vector of SR, energy is associated with the time coordinate and momentum is associated with...

Mar109 04:13 PM
atyy

7 
1,190 
Suppose that I have a source of monochromatic light of which I can lower that intensity so that it emits one photon,...

Aug2909 10:00 PM
alexepascual

9 
2,933 
It seems like if you accelerated a massive particle to a high enough velocity (momentum), you could get it's...

Apr1910 01:22 AM
IttyBittyBit

15 
5,731 
Suppose I setup a doubleslit experiment and run it for, say, 15 minutes. Nothing in the experimental setup changes...

Nov2509 10:30 PM
referframe

0 
514 
Suppose we are given an arbitrary multiparticle quantum system whose state function / probability density does not...

Dec809 03:31 AM
dmtr

1 
1,551 
It seems to me that, by definition, QM particles are localized in time.
A “particle” in QM and the act of measuring...

Jan1410 01:41 PM
elibj123

1 
1,122 
Consider a free particle traveling in one dimension represented by a wave packet with a Gaussian amplitude function. ...

Jan3010 03:32 PM
referframe

0 
830 
When a photon encounters a beam splitter, say a halfsilvered mirror, there is a 5050 chance it will be reflected or...

Feb110 01:37 PM
Peter Morgan

3 
809 
Will a doubleslit experiment work (exhibit an interference pattern) with a source of photons that is just...

Feb1410 11:54 AM
the_house

3 
1,015 
Energy (frequency) and Time are related via the Fourier Transform of the Wave Function. A quantum state has to hang...

Feb2310 11:41 AM
referframe

2 
927 
In a paper in Physical Review A, the author discusses a wave function for one particle, Ψ(r,t), where r is the...

Apr1610 01:46 PM
SpectraCat

1 
1,522 
Wave functions are, of course, almost always complexvalued. In all of the examples that I have seen (infinite square...

Apr1710 02:35 PM
referframe

0 
3,570 
In nonrelativistic wave mechanics, the momentumposition uncertainty relationship and the energytime relationship...

May410 03:29 AM
Demystifier

5 
2,676 
An alphaparticle produced by radioactive decay leaves a visible continuous track in a Wilson Cloud Chamber. As it...

May1010 03:25 PM
humanino

1 
904 
Most of the literature that I have read on nonrelativistic wave mechanics discusses experiments that measure a...

Sep1810 09:46 AM
sweet springs

18 
3,865 
Massive particles have a rest energy, m0c2, and therefore a matching rest or intrinsic frequency.
So, does that...

May2810 05:36 PM
sweet springs

17 
1,732 
A Gaussian function is often chosen as the amplitude function for the wave packet of a single particle. It is handy...

Jun1710 10:15 AM
alxm

2 
790 
What does the Ground State of a quantum simple harmonic oscillator represent physically?
Thanks in advance.

Jul1110 09:46 PM
jtbell

9 
2,161 
The Hermite Polynomials are solutions to the Schrödinger equation for the Quantum Simple Harmonic Oscillator. But the...

Aug1510 08:25 PM
jtbell

1 
1,310 
Consider the doubleslit experiment using a lowintensity source of monochromatic photons: If the intensity is low...

Aug1510 07:57 PM
referframe

2 
957 
Consider 2 entangled fermions. If the spin direction of one particle is measured, then the spin direction of the...

Jun1311 08:41 AM
Demystifier

6 
902 