Recent content by gentzen

I guess you meant (copy&paste mistake): https://arxiv.org/abs/1712.06605

As long as you are requiring exact symmetry, my answer to QuarkyMeson above provides one answer: If everything is exactly symmetric down to the last detail, then one can simply take the quotient and get a reduced description. So this means that only the FAPP situation is interesting for your...

So the small part broke the symmetry, no? And not just for itself, but globally! Or maybe not, if we assume that another indistinguishable small part also exist, as required by the symmetry under that 180° spatial rotation about a fixed axis. The interesting question is what "indistinguishable"...

A frequently used model has an effectively asymmetric environment: No idea whether you could come up with a model with an environment respecting your 180° spatial rotation about a fixed axis. The points 1. - 4. seem unproblematic to me. Point 5. should be unproblematic too, depending on how...

Here is the relevant passage from the paper (bold emphasis by me): Alfred Landé and Werner Heisenberg had defended such half-integral quantum numbers in 1921. This caused skepticism and critique. I would interpret this passage as a defence of that earlier work, hinting that it had always been...

Are you sure that it is on page 12? I couldn't find it there. And I am too lazy to ocr this document to make it searchable.

You know https://arxiv.org/abs/quant-ph/0608140 (1951 Lectures on Advanced Quantum Mechanics Second Edition by Freeman J. Dyson)? But of course, even if you don't know this text, you certainly know these arguments. But maybe the last bold sentence above (bold by me) helps you at least a bit...

I guess there are not too many things to do with them. You could analyse their position-momentum uncertainty, you could analyse the 2D or 3D harmonic oscillator and its radial symmetry. And maybe two or three other things, but then it soon gets boring. Plane waves are simply more interesting...

yes

In the link, the part in bold above refers to functions from the Schwartz space. The Schwartz space is the function space of all functions whose derivatives are rapidly decreasing. The Hermite functions are functions from the Schwartz space, so in this sense the part in bold also refers to...

Yes :smile: The Hermite functions are such a Hilbert basis. They are eigenfunctions of the Fourier transform. They are well localized in both position and frequency space, and this is not untypical for a Hilbert basis. If you scale them, you get another Hilbert basis, which no longer consists of...

As much as I like PF, it is no alternative to Stack Overflow for surviving the subtleties, inconsistencies and implementation bugs of existing programming languages and coding tools. And I am thankful that I don‘t need to ask those questions there myself, because waiting hours, days, or even...

Maybe not an electrostatic field, but shooting an electrodynamic field at somebody's head is possible. It normally won't hurt, and often it will also be more extended than the head. But that is just because the speed of light is so fast.

I initially didn't refer to any specific question, but you are right, in the end that was the question MBastieK wanted to discuss. And my "update" today is certainly also related to that question, because it weakens my explanation for why In that discussion with MBastieK, I also raised that...

Since I know that you can read German, my discussion on Physikerboard with MBastieK of such a "don't exist" or "no well defined properties" question for a very simple and specific case could be interesting: In a later reply to bhobba it is mentioned ("The issue of this slight modeling...