Saturday, March 14, 2015

The Lightness of Being: Book Review

The Lightness of Being: Mass, Ether, and the Unification of Forces by Frank Wilczek.

Wilczek's book is aimed at the public, but it has a lot that I, a physicist whose experience has been distant from particle physics, found revealing and insightful. His themes are the modern version of the ether, which he calls the Grid, the origin of mass, and the unification of physics. At the center of these is the standard model, which he likes to call the Core, and especially Quantum Chromodynamics, or QCD, his contribution to which won him the Nobel Prize.

It's focused squarely on the underlying ideas though there are a small number of those personal anecdotes that enliven many popular accounts of physics. His seem chosen to illustrate physics more than personality. One I liked was his account of how he baited Murray Gell-Mann (the inventor of quarks) by telling him that he was working on improving Feynman's Parton Model, which had been formulated to explain the results of probing nucleon structure using high energy electron beams. This provoked a bit of a tantrum from Gell-Mann, who fulminated against Feynman's "put-ons" and his supposed pollution of the lexicon of physics. Of course they are just quarks, said Gell-Mann.

But Gell-Mann was wrong and Feynman was right. The probing electrons had indeed seen quarks, but they had seen something else as well, the gluons, and that was crucially important, because the gluons were the force carriers of QCD - the glue that held nucleons and mesons together.

Wilczek traces the history of the concept of a space filling ether, and finds that physicists from Descartes, to Newton, to Einstein to Feynman had a turbulent relationship with it, but that the ether finally won. Wilczek prefers to call it the Grid - a multi-layer superconductor seething with virtual particles and. The superconducting he refers to is not ordinary electromagnetic superconducting, but color and weak charge superconduction, screening and anti-screening, and giving mass to many of the particles of the standard model.

I even read the glossary at the end, not because I didn't know what charge or acceleration were, but for the interesting little tidbits of insight that he throws in. I recommend the book, though some parts might be a bit challenging for someone with no physics background.

Fans, like YHC, of the monumental Princeton Companion to Mathematics, edited by Tim Gowers, might be interested to know that Wilczek is editing a Princeton Companion to Physics, scheduled for 2018 publication.