How big a planet do we have to have to create 267 GPa pressure at the center? Is the temperature in the center of a planet necessarily too high for superconductivity ? I'm trying to imagine a big enough, cold enough planet with a superconducting core. Would such a planet have peculiar enough properties to be visible from lightyears away? At 05:55 PM 10/15/2020, Eugene Salamin via math-fun wrote:

Superconductor at 15 C, but at 267 GPa pressure.

https://news.yahoo.com/super-material-raises-hope-energy-094906169.html

https://www.nature.com/articles/s41586-020-2801-z

-- Gene

Hello math-fun, The pression at the center of the earth is about 360 Gpa but, it is a little difficult to get there. (source wikipedia). Best regards, Simon Plouffe Le ven. 16 oct. 2020 à 02:56, Eugene Salamin via math-fun < math-fun@mailman.xmission.com> a écrit :

Superconductor at 15 C, but at 267 GPa pressure.

https://news.yahoo.com/super-material-raises-hope-energy-094906169.html

https://www.nature.com/articles/s41586-020-2801-z

-- Gene _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun

Interesting example of inversive relation between temperature and pressure. As long as entropy decreases, long-range order is easier to achieve. But the article doesn't seem to say if the transition at 225 GPa is related to breakdown of free-space valence expectations. Is anyone else bothered by the idea of H3S at 155GPa? How should the Schroedinger equation be solved with pressure as an explicit variable? This is not the "particle in a box"... Since the theory apparently hasn't been done above 4 GPa, we are left to speculate about what the solid geometry would look like. Is H4S achieved? Is the solid structure diamond cubic? Some interesting questions to think about, but I can't afford the rosy idea from yahoo that we won't need batteries anymore: "With this kind of technology, you can take society into a superconducting society where you'll never need things like batteries again," Some research at UofA was also in the news recently: https://phys.org/news/2020-10-physicists-circuit-limitless-power-graphene.ht... And actually this looks promising. The reference to Feynman is about "Ratchet and Pawl", see also: https://www.feynmanlectures.caltech.edu/I_46.html --Brad On Thu, Oct 15, 2020 at 7:56 PM Eugene Salamin via math-fun < math-fun@mailman.xmission.com> wrote:

Superconductor at 15 C, but at 267 GPa pressure.

https://news.yahoo.com/super-material-raises-hope-energy-094906169.html

https://www.nature.com/articles/s41586-020-2801-z

-- Gene _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com https://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun