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1answer
126 views
+50

SUSY and van der Waerden spinor notation

I am currently trying to read into SUSY and I am running into trouble with the van der Waerden spinor notation for Weyl spinors. I am looking for resources that construct and justify the index ...
2
votes
1answer
108 views
+50

Relation between antiparticle and the Dirac conjugate? bar symbol

The Dirac conjugate is defined as $$ \bar{\psi} = \psi^{\dagger}\gamma^0 $$ where $\psi$ is a spinor (4 dim for spin 1/2) that can describe a mixture (direct sum?) of fermion and anti-fermion states. ...
2
votes
1answer
159 views
+50

Young's “double double slit” experiment

The set-up is shown in the image above. Find the intensity on the screen as a function of $y$, and $I_0$, where $I_0$ is the intensity of the central maxima. I recognize that the plane wavefront ...
6
votes
3answers
453 views
+50

How does time-translation symmetry morph into evolution in time?

I am reading Ballentine's textbook "Quantum Mechanics: A Modern Development". In it he transitions from discussing time-symmetry to discussing evolution (of the state) in time. I'm finding it ...
3
votes
0answers
38 views
+100

Primordial color charge fluctuations that failed to die out due to cosmic inflation

We know that ripping the quarks in a hadron apart will not give us free quarks, but rather new (anti-)quarks are generated that neutralize the color charges of the quarks. We also know that the total ...
0
votes
0answers
56 views
+100

Preventing parasitics for wires?

This is in relation to my question One-way magnetic shielding? where the correct answer gives some links to the material. My question is, does this material, one-way magnetic/electric shielding ...
1
vote
2answers
68 views
+50

Intuition behind hydrostatic force/pressure being applied laterally

I can understand how the downward vertical force is being applied: due to the weight of the water column directly above it. However, I cannot understand how the lateral and the upward forces act. How ...
1
vote
0answers
58 views
+100

Derivation of the refractive index dependency of the light-matter interaction hamiltonian

I tried to derive a relation of the light-matter interaction Hamiltonian in vacuum and a medium that is characterized by a linear real refractive index but I am not sure if the following is correct or ...
3
votes
1answer
68 views
+50

Calculating cyclotron orbits in a lattice

I have a naive question, is it possible to obtain the wavepacket dynamics that give rise to cyclotron orbits from a real space tight-binding Hamiltonian? Consider a square lattice in the presence of a ...
0
votes
1answer
64 views
+50

Can we predict harmonic generation from Maxwell's equations?

One typical experimental setup to generate harmonics from a laser pulse is to irradiate some plasma stab with a laser, register both reflected and transmitted waves, and the spectrum of those waves ...
0
votes
1answer
89 views
+100

Which quantity is minimized in energy balance models

In zero-dimensional energy balance models (EBM) of the atmosphere one may consider in the most simple case the differential equation $$k\,dT/dt = \alpha - \beta T^4$$ with heat capacity $k$ of unit $[...
2
votes
0answers
90 views
+50

Realistic String Theories without Supersymmetry

In a podcast with Cumrun Vafa (https://www.youtube.com/watch?v=yppqz12ngbM&t=654s with the relevant part from 35:30 to 35:50), Vafa mentioned that there exists string theories that can describe ...
0
votes
0answers
32 views
+50

How to detemine the phase profile of a time-harmonic planar field incident upon a lens rigorously?

$\renewcommand{\vec}[1]{\boldsymbol{#1}}$ $\renewcommand{\hvec}[1]{\hat{\boldsymbol{#1}}}$ In Optics f2f, the author solves for the phase of the a plane wave of frequency $\omega$ propagating along $\...