ComPhys @comphys@qoto.org

What do you think of this article on the education of physics?

https://physicsworld.com/a/building-a-physics-degree-for-the-future-five-key-questions-we-need-to-answer/

Something which often concerns me about opinion pieces like this, is that employability, which was until recently a side effect of having a physics degree, seems to have become the primary goal. The first example in the article says
"[...] during which they apply their learning to solve research or technical problems based on global challenges, possibly posed by businesses." However notably, physics challenges aren't mentioned.

Encouraging children to learn from online resources, rather than textbooks is also (currently) a mistake; as they are in my experience very often inferior. Whilst a mix of resources is probably the best, I have encountered students who genuinely believed that watching a 3blue1brown video was in some way equivalent to doing exercises themselves. Students starting university need to be told what the best resources are, we shouldn't be simply accept their potentially inferior preferences. Find me a single online resource better suited to teaching Fourier Transforms than Robert Bracewell's textbook, and I'll reevaluate my opinions.

I actually agree that exam grades can be misleading and maybe there is a better way to assess. Everybody I know who got good grades, myself included, crammed before exams, and I'm not convinced if that really represents a mastery of the subject; although it does demonstrate work ethic, dedication, ability to learn etc.

The suggestion to reduce time in the lab is just downright wrong. We need to be improving our students practical abilities by expanding lab work and making it far more integral to the learning process and maybe even the assessment process. I've seen high-grade, covid generation students confused why their circuits didn't work with only one end of a battery connected. In my opinion, that was brought about by a lack of opportunity to turn their theoretical knowledge into real world knowledge. Students like that are leaving university without the skills to contribute to making technology for physics or addressing global challenges.

In my opinion, physics degrees should adapt to meet physics needs, and we should accept employability for whatever it is after that. If physics graduates become less employable then so be it; it's natural that desirable skills change with time (although physics skills are definitely important at the moment). Fundamentally, physics degrees should never be allowed to become generic workplace training courses.

A short post on evaluating the Fourier integral numerically. https://comphysblog.wordpress.com/2023/07/06/computing-fourier-integrals/

When I tried to look up how to do this, I almost exclusively found information on the FFT. This gave inadequate results, which I now know is expected. Numerical recipes says:

"It is a sobering exercise to implement equation (13.9.6)[DFT] for an integral that can be done
analytically, and to see just how bad it is."

This week I came across zenodo.org. It issues doi's for datasets (or other things) that you upload, and it's apparently hosted on CERN infrastructure. I wish I had found this earlier.

@freemo I was confused earlier on by a minicircuits spec sheet for a 180 degree hybrid [1]. They only seem to sell three port varieties, I assume they fourth port is internally terminated or it isn't included somehow. Now the thing which confused me was that they referred to one of the ports as the SUM port. Hybrid couplers are often shown as 4 port devices with Sigma, Delta 1 and 2 ports. I would have thought the "SUM" port would be the sigma port, but then the output of the splitter would be two in-phase signals and it wouldn't really be much of a "180" degree" hybrid. Their SUM port must correspond to the Delta port, that is, the signal out of the "sum" port would be large if the inputs at ports 1 and 2 were entirely out of phase, I.e. the difference. It does behave this way, I tried it today, but my question is: why would they call it a "sum" port when if anything it's subtracting?! Am I alone in finding that confusing?

[1] - https://www.minicircuits.com/WebStore/dashboard.html?model=ZFSCJ-2-1

Does anybody have any experience with designing thermally stable HF filters (100's of MHz)? Any references appreciated :)

Finally made my 2D magnet post. In this example I do a simple demonstration of finding a magnetic field from a coax, and verify the result with an analytical solution. I then use the same method to find the field inside a dipole magnet of the type used at the LHC; a cos(phi) magnet. https://comphysblog.wordpress.com/2020/08/19/2d-magnetostatics-cos%cf%86-dipole-magnet/

#fenics #physics #finite_element_analysis