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Friday, April 08, 2022

Brief items

It's been a while since the APS meeting, with many things going on that have made catching up here a challenge.  Here are some recent items that I wanted to point out:

  • Igor Mazin had a very pointed letter to the editor in Nature last week, which is rather ironic since much of what he was excoriating is the scientific publishing culture promulgated by Nature.  His main point is that reaching for often-unjustified exotic explanations is rewarded by glossy journals - a kind of inverse Occam's Razor.   He also points out correctly that it's almost impossible for experimentalists to get a result published in a fancy journal without claiming some theoretical explanation.
  • We had a great physics colloquium here this week by Vincenzo Vitelli of the University of Chicago.  He spoke about a number of things, including "odd elasticity".  See, when relating stresses \(\sigma_{ij}\) to strains \(u_{kl}\), in ordinary elasticity there is a tensor that connects these things: \(\sigma_{ij} = K_{ijkl} u_{kl}\), and that tensor is symmetric:  \(K_{ijkl} = K_{klij}\).  Vitelli and collaborators consider what happens when there is are antisymmetric contributions to that tensor.  This means that a cycle of stress/strain ending back at the original material configuration could add or remove energy from the system, depending on the direction of the cycle.  (Clearly this only makes sense in active matter, like driven or living systems.)  The results are pretty wild - see the videos about halfway down this page.
  • Here's something I didn't expect to see:  a new result out of the Tevatron at FermiLab, which is interesting since the Tevatron hasn't run since 2011.  Quanta has a nice write-up.  Basically a new combined analysis of FermiLab data has a new estimate out for the mass of the W boson along with a claimed improved understanding of systematic errors and backgrounds.  The result is a statement that the W boson is heavier than expectations from the Standard Model by an amount that is estimated to be 7 standard deviations.  The exotic explanation (perhaps favored by the inverse Occam's Razor above) is that the Standard Model calculation is off because it's missing some added contributions from so-far-undiscovered particles.  The less exotic explanation is that the new analysis and small error estimates have some undiscovered flaw.  Time will tell - I gather that the LHC collaborations are working on their own measurements. 
  • This result is very impressive.  Princeton investigators have made qubits using spins of single electrons trapped in Si quantum dots, and they have achieved fidelity in 2-qubit operations greater than 99%.  If this is possible in (excellent) university-level fabrication, it does make you wonder whether great things may be possible in a scalable way with industrial-level process control.
  • This is a great interview with John Preskill.  In general the AIP oral history project is outstanding.
  • Well, this is certainly suggestive evidence that the universe really is a simulation.

2 comments:

Anonymous said...

People talk a lot about the ill-effects of Nature and Science publishing culture, but honestly I can't see anything changing. Mazin's letter is sharply written, but can we collectively take serious action? I can only see a significant difference being made at the funding agency level.

Anonymous said...

Regarding the article by Mazin, I am honestly curious, is there an opposing side to that argument? If so, what do they say in defense of the publishing style of Science and Nature? I am sure the high powered groups at many universities are not totally dissatisfied with how publication culture has changed.