I got back from an an international meeting about neutrinos: solar neutrinos—supernova neutrinos—accelerator neutrinos—reactor neutrinos—black body neutrinos. I know this sounds a bit like one of those restaurants where all the courses are made out of garlic, but that's the way frontier science often is these days. Specialize or perish. By the way I don't recommend this approach for restaurants.

Anyway these little particles are fascinating, so numerous that they may represent the dominant mass in the universe and so weakly interacting that they easily go through miles of rock without being slowed down, hardly ever leaving an observable trace. No pictures of them in this card, but let me assure you they are everywhere.

Attended by over 400 people, the meeting was interesting sociologically as well as scientifically because of the presence of groups building or planning to build new neutrino detectors. Not all of them are going to make it so there's a lot of jockeying for position. In presenting plans, the experimentalists seem to have introduced a new unit, the MegaEuro per Kiloton, ME/KT, designed to let others know how big their detector is going to be and how cost efficient it really is. Every detector is also labeled by its own acronym, designed hopefully to stick in the mind. SNO, AMANDA, BOONE, UNO, MINOS, LUNA, MOON, MIND and so on were all discussed- note the letter "n" for neutrino tucked away somewhere in all of them. Only the two veterans, Homestake and Kamioka, were named for the mine and the mountain they were located in. Those were the old pre cute days. Ultimately of course, it's the results, not the acronyms that matter.

The meeting was held in Munich, a city I hadn't been to in almost 15 years. While there I started feeling that I was living in one of those Sebald books where truth and fiction, past and present begin to merge in eerie ways. My thoughts centered on November 1918, the month 18-year old Wolfgang Pauli arrived in Munich from his native Vienna. He intended to study at the university. Study may be the wrong word because Pauli was generally considered to be the smartest of all the wunderkinder that created quantum mechanics. At 20 he wrote the review article about general relativity-it amazed Einstein. At 24 he did the work on the Exclusion Principle that won him the Nobel Prize. Heisenberg, Pauli's slightly younger Munich buddy tends to get more credit these days, but it's not clear to me how much of Heisenberg's work is due to Pauli's prodding. Together and separately, they were a formidable duo. However the idea of the neutrino was Pauli's and Pauli's alone.

November 1918 also had a dark side in Munich because that's when a disgruntled war veteran named Adolf Hitler moved there, with consequences that are all too familiar. On a personal side, both my mother and my mother-in-law came to Munich that same month from other towns in Germany- once World War I was over there seemed to be a general migration of young and aspiring Germans to either Munich or Berlin. For a while, things looked good, but within a few years the tide began to turn. My mother moved to Italy, explaining how her son came to be named Gino. My mother-in-law stayed in Munich, fleeing only after the Nazis murdered her first husband. My Munich roots, both good and bad, run deep.

Then of course there is the city's English Gardens, the vast park designed by Count Rumford, a Massachusetts native who fled to Britain after picking the wrong side to back in the Revolutionary War. He founded the Royal Institution, the famous London research institute and then left for Bavaria to re-organize their army. While in Munich he managed to deal the caloric theory a near-fatal blow by finding the mechanical equivalent of heat. After a while he came back to London and soon thereafter, in a huff, headed off to France, then at war with Britain. In Paris he married the widow of the great chemist Lavoisier, who had been executed in the French Revolution. The marriage didn't work out, but fortunately the science did.

Clearly I needed a bit of time to digest all this and what better place than Martha's Vineyard in June. Am now back in Philadelphia.
July 1 is the publication date of my A Matter of Degrees, a book that incidentally features solar neutrinos, Count Rumford and global warming. Appropriately enough, we're in the middle of a heat wave.



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