Roberto Pavani's latest activity

1.21 ggigawatts.

What you're describing is essentially a passive Fabry-Pérot cavity. This is actually a well-known setup — the intracavity field can be...

The answers above are correct. Just adding a safety note: any laser above ~500 mW (Class 4) requires proper eye protection, not just...

There are two kinds of lasers, continuous wave (CW) and pulse. Since you're thinking of CW, that is what I will address. Most CW...

Agreed. And more generally by Dirac's equation for relativistic particles. The entanglement is already in the formalism, no extra axiom...

It is. If you take some wavefunction, in which there is no entagelment between particles, and fitting hamiltonian for particles in this...

Certainly. The potentials are often more direct, convenient, or easier.

If you meant the (magnetic) 3D-vector potential ##\vec A##, yes, I think in the lab frame it comes mainly via the magnetic field ##\vec...

Yes, I think I was expressing roughly the same thing in a less rigorous way. Thank you for the precise formulation. What I was...

They are caused by electromagnetic forces, not by ##A## itself. In 4D-Spacetime Algebra, the electromagnetic field bivector is...

It seems to me that the deformation forces are all caused by ##\nabla A## ?

This is an interesting link. I think a convincing explanation is the following, because a magnetic field only from the moving part of...

You're right, I overstated the symmetry, B is not zero at the bar. My mistake. Still, I notice that explaining the force on the bar...

Is this the scenario? https://kirkmcd.princeton.edu/examples/hairpin.pdf

@Dale I've found an interesting link: http://www.ampere.cnrs.fr/histoire/parcours-historique/lois-courants/force-obsolete/eng...