Friday, January 31, 2014

Neutrinos! (Linus Pauling Memorial Lecture)


Dr. Ray Jayawardhana was good-natured about taking some cliche questions, like had he met Arthur C. Clarke, the famous expat and Sri Lankan science fiction writer.  Yes he had.

A native of Sri Lanka (aka Ceylon going back), Ray turned himself into a kind of astrophysicist.  He's from the University of Toronto these days and has just had a book published:  The Neutrino Hunters.

As a planetologist more than a quantum mechanics specialist, he was not equipped to get really detailed about why tau neutrinos seem harder to trap or only were recently or whatever it was.  The neutrino appears to undergo phases in travel so your cross section is only 1/3rd of the expected -- a way of spending more energy in travel I suppose, accounting for apparent energy loss.

Conservation of Energy was a core theme of his talk.  Quantum mechanics was facing some serious problems with beta decay, as the resulting energy particles did not seem to add up -- reversibility was violated.  Wolfgang Pauli couldn't make the conference but wanted his idea on the table:  another particle.

At that point, for the longest time it seemed they would be impossible to detect, another kind of theoretical dead end, a disconnect from the empirical warp and woof and the substance of science's narrative.  However this barrier to empiricism was overcome in the form of giant tanks in deep mines, all other cosmic rays filtered.  Any weak force interactions (the only kind involved) would have to be owing to neutrinos.  At last they'd been found.

Jayawardhana started his talk with some mock poking of fun at all the Higgs Boson hype, the recently detected empirical blip needed to sustain QM's standard model, an important puzzle piece.

Neutrinos are as mysterious and spooky as ever, lets not become too taken with Higgs.  Neutrino hunters get to go on adventures deep underground, or to Antarctica.  Lets keep their profession alive.

Astrophysics sure could use a nice supernova around now.  All the neutrino detectors are poised to receive data.  A new generation of instruments is in place.

They just don't happen all that often.  Maybe one a century of the kind he meant.

The neutrinos from such an event get here first, not because "faster than light" but because the photons get slowed down by electromagnetic phenomena, have to put on a fireworks show.  Neutrinos are largely indifferent to matter and are just "outta there" so get here sooner, as news of a cosmic broadcast.