Involving quantum mechanics: In an enormously complicated 165-page paper, computer scientist Zhengfeng Ji and colleagues present a result that penetrates to the heart of deep questions about math, computing and their connection to reality. It’s about a procedure for verifying the solutions to very complex mathematical propositions, even some that are believed to be impossible to solve. In essence, the new finding boils down to demonstrating a vast gulf between infinite and almost infinite, with huge implications for certain high-profile math problems. Seeing into that gulf, it turns out, requires the mysterious power of quantum physics. Tom Siegfried, “How a quantum technique highlights math’s mysterious link to physics” at ScienceNews It’s not entirely clear why a link between physics and Read More ›

JStanley’s comment here put me in mind of this photograph I took in a Xian market some years ago.

. . . and that, at about the suggested time for an up-turn. Astronomy telegram clip: >>The Fall and Rise in Brightness of Betelgeuse ATel #13512; Edward Guinan, Richard Wasatonic (Villanova University),Thomas Calderwood (AAVSO) and Donald Carona (Texas A& M University) on 22 Feb 2020; 12:59 UTCredential Certification: Edward Guinan (edward.guinan@villanova.edu) As previously reported (see ATel #13365, #13410 and #13439), the red supergiant Betelgeuse has been undergoing an unprecedented decrease in its visual (V) brightness since October 2019. Photometry secured over the last ~2 weeks shows that Betelgeuse has stopped its large decline of delta-V of ~1.0 mag relative to September 2019. The star reached a mean light minimum of = 1.614 +/- 0.008 mag during 07-13 February 2020. This Read More ›