Wednesday, September 28, 2022

News items, Nobel speculation

 Some news items of interest:

  • Three weeks old now, but this story about IBM cooling down their enormous dilution refrigerator setup got my attention (as someone with ultralow temperature scientific roots).  IBM did this to demonstrate that this kind of large-scale cooling is possible, since it may be necessary for some implementations (whether superconducting or spin-based) of quantum computing.  To give a sense of scale, Oxford Instruments used to rate their dilution refrigerators based on their cooling power at 100 mK (how much heat could you dump into the system and still have it maintain a steady 100 mK temperature).  The system I worked on in grad school was pretty large, a model 400, meaning it had 400 microwatts of cooling power at 100 mK.  The new IBM setup can handle six dilution refrigerator units with a total cooling power of 10 mW (25 times more cooling capacity) at 100 mK, and with plenty of room for lots of electronic hardware.  Dil fridges are somewhat miraculous, in that they give access to temperatures far below what is readily available in nature thanks to the peculiarities of the 3He/4He mixture phase diagram. 
  • This retraction and the related news article are quite noteworthy.  The claim of room temperature superconductivity in carbon-containing hydrogen-rich material at very high pressures (written about here) has been retracted by the editors of Nature over the objection of the authors.    The big issue, as pointed out by Hirsch and van der Marel, is about the magnetic susceptibility data, the subtraction of a temperature-dependent background, and concerns whether this was done incorrectly (or misleadingly/fraudulently).  
  • Can we all agree, after looking at images like the one in this release, that STM and CO-functionalized-tip AFM are truly amazing techniques that show molecules really do look like chemistry structural diagrams from high school?
  • Quanta magazine has a characteristically excellent article about patterns arising when curved elastic surfaces are squished flat.  
  • They also have an article about this nice experiment (which I have not read in detail).  I need to look at this further, but it's a safe bet to say that many will disagree with the claim (implied by the article headline) that this has now solved the high temperature superconductivity problem to completion.  
And it's that time of year again to speculate about the Nobel prizes.  It would seem that condensed matter is probably due, given the cyclic history of the physics prize.  There are many candidates that have been put forward in previous years (topological insulators; metamaterials; qc lasers; twisted materials; multiferroics; anyons; my always-wrong favorite of geometric phases) as well as quantum optics (Bell's Inequalities).  I suspect the odds-on favorite for the medicine prize would be mRNA-based vaccines, but I don't know the field at all.  Feel free to gossip in the comments.


DanM said...

I'll put my chips on Dave Smith and John Pendry this year.

Anonymous said...

Ok I'm curious, to what extent do PI's get a say in objecting to a PR title? Do they authors really believe high Tc is finally understood?

My impression of the paper is that it is providing evidence that Tc and the charge transfer energy are directly correlated. This isn't a causal relationship though, since we don't have a clear grasp on the mechanism. So from my view, the paper cannot possibly support the title of the PR, so what gives?

Anonymous said...

I don't get how metamaterial might reach Nobel Prize level. What concrete and significant benefit do metamaterials bring us? Except that the topic does produce a huge amount of glossy publications.

Douglas Natelson said...

Anon@3:53, this is an article in a magazine, rather than a PR release put out by their home institution, so I’d think the PIs probably had zero say in the headline. There is a decent chance that the actual article author also had very little control over the headline, if my past experiences are a guide.

Anon@8:08, it’s pretty hard to argue that photonic band gaps and optical meta materials didn’t open whole new areas of investigation. For the latter, it does look like various flat optics applications are going to have real technological impact in devices. The Nobel is also not all about tangible benefit. Gravitational wave detection doesn’t bring tangible benefit but is nonetheless intellectually significant.

Anonymous said...

I feel photonic band gap is a more intelectual contribution. From people with microwave engeneering background there are real reserved judgement on metamaterials and metasurfaces as novel ideas. As for flat optics applications, they are great but appear more engineering. I don't see what essential physics the metasurface concept has in there. "They are merely gradient frequency selective surfaces at optical frequencies" - I can imagine microwave engeneering people may comment on this :p

Anonymous said...

The retraction really is an embarrassment for Nature, its reviewing standards for extraordinary claims, and the reviewers they used. As for the authors, instead of relying on the robustness of their data and their analyses, they roll out the PR statements and the lawyers. Really unbecoming and disgusting behavior for scientists.

Anonymous said...

Personally, I have 100% confidence that this would not have passed through publication in PRL or PRB despite the lower impact factor.

I suspect the claim of metallic hydrogen by the same corresponding author published in Science is also incorrect - the evidence there is also murky.

Steve said...

My Nobel prediction is quantum information sciences. Options:

Group 1: David Deutch and Peter Schor

Group 2: Alain Aspect and Anton Zeilinger

Group 3: Scholkopf, Devoret, Martinis.

If I had to guess one of them, I think Group 2 is the strongest case.

Steve said...

Victory dance! (first time I've guessed right in a while)

DanM said...

Aspect et al. is a good prize. No question.

I will re-up my guess again in future years. Negative refraction was called "impossible" by numerous smart people until David Smith did the experiment to demonstrate it (and some even continued to call it impossible after that). Surely a Nobel-worthy accomplishment, IMHO, even for people with a microwave background (which, by the way, includes David).

Anonymous said...

Good call!