While looking for something else the eyes fell upon a gem that reminds one that, for all the work most science journalists put into turning science- and math-talk into plain language, not too many including me very often take dives deep enough to bring a twinge of comprehension, a near-sharing of the exhiliration felt by top notch scientists noodling at the rim of the noosphere. Especially in theoretical – maybe I should say hypothetical – physics.
Here are two recent numbers from a man – and old pal – who does it all the time much to the amusement and occasional befuddlement of colleagues:
- Science News – Tom Siegfried (Jan 15) 'QBists' tackle quantum problems by making science subjective and (Jan 21) Gell-Mann, Hartle spin a quantum narrative about reality ;
Tom was until recently editor of Science News, where he regularly threw a freelance assignment my way thank you very much. He stepped down but lives on within this worthy magazine and news service as a regular columnist and essayist blogger. He as always writes on whatever strikes his fancy, as far as I can tell. That usually means the weirdness of physics theory. That further means the thoughts by some of the world's smartest people about the stone-truth reality we all share. In this case he goes off on the continuing perplexities set off by the revolutions in physics of the early 20th century, particularly quantum mechanics with its clouds of probability and wave functions collapsing on cats-in-boxes and dualities and entanglements and god-playing-dice conundrums. The second one of this two-parter zeroes in on a marvelous paper on the arXiv magical server of often-nascent manuscripts that may or may not eventually qualify for formal publication (this one surely shall) :
- Murray Gell-Mann, James B. Hartle: Adaptive Coarse Graining, Environment, Strong Decoherence, and Quasiclassical Realms ; The illus for this post is a snip from the paper with a passage evocative and gob-smacking.
The paper, by two smart and famous physicists (esp. Gell-Mann), is the latest episode in a struggle to make sense of how the future becomes the past, switching from a skein of possibility into narrative story or stories and the role that actors in the present play. That latter lot includes the declaration that scientists doing their experiments are not just neutral witnesses reading the story of everything but to an extent interfering and hence dictating it as it unfolds. Something like that. This sort of thinking is related to logical inferences that maybe the universe bifurcates endlessly as time goes by, spawning infinitely diverging semi-clones that express different ways random and suspended quantum possibilities can crystallize.
See, not too many science journalists visit such topics except, perhaps, as a way to wow readers with mind-numbing theories before returning to more solid topics, like whether the latest blizzards refute or underscore global warming.
Tom studied physics long enough – into graduate school – to read it if not do it anymore. That's better than most of us. He also is a journalist to the core. Reading this and examing the similes and metaphors and quick asides he uses to relax readers' brains and to keep the topic chatty, if not transparent, is a pleasure. So is reading that paper. Not that I can claim to have learned much. But even the lay eye can pick up enough to recognize that Siegfried read it deeply, and to see further that one cannot dismiss it as intellectual pushups with no connection to the real world. More likely, it deeply addresses the commonplace.
I'll quote just one passage from the paper that'll get your brain running, even if you can't quite explain why:
[We aim] at characterising the realistic quasiclassical realm(s) of our quantum universe as particular kinds of decoherent sets of coarse grained alternative histories defined by quasiclassical variables. To this end we introduce three new (connected) ideas: branch dependent adaptive coarse grainings, a general notion of a narrative set of alternative histories, and a notion of strong decoherence to characterize realistic mechanisms of decoherence."
So simple, eh? Here's the meaning I choose to collapse from it: "..a narrative set of alternative histories" is what a journalist's rough drafts are, and "strong decoherence" is what editors do to the draft submitted.
Science News Magazine and its full specrum of additional on line offerings continue to be superb. To see what else Siegfried has contributed via his carefully crafted blogs go here.
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