What Luis Alvarez Did

Me & Ann & Ben had a Twitter conversation that turned into an email conversation that turned into a google doc.  Next thing I knew, here I am Writing With Real Writers.  I have arrived, biotch!!!

Ben:  OK, everyone. Forget Tesla. It’s time to start obsessing about Luis Alvarez.

Ann:  Oh, I’ve heard of him.  He was a famous physicist.  And he and his son, Walter, did something important about dinosaurs but I forget what. But I think they did that later on.

Ben:  Right. This even starts out crazy. For his graduate work, Alvarez helped discover that cosmic rays are partly made of antimatter. I still meet (well, tweet) people who think anti-matter is fiction. But no, it was found in 1932. Today it’s so common we use it for medical procedures (such as PET scans). Later he also used cosmic ray muons to search for hidden chambers in the pyramids at Giza.

Ann:  During the second World War, he invented the aircraft blind-landing system.  And according to another Alvarez-enthusiast, @andrewtlloyd, while Alvarez was working on the landing system, he met Arthur C. Clarke and Clarke based his novel “Glide Path” on him.

Ben:  OK, and then it turns out that Luis Alvarez was flying in formation with the Enola Gay when it dropped the atomic bomb on Hiroshima.  And @andrewtlloyd said that the name of the plane Alvarez was on was Great Artiste, and that during the next bombing run, on Nagasaki, he dropped this letter to a Japanese scientist he knew. !!

Ann:  And after the war, he and Edward Teller pushed for the next biggest bomb — the H bomb, the Super — that nobody else wanted.

Ben:  Oh, I forgot the part where Alvarez won the Nobel Prize for *improving* the design for the Bubble Chamber. This guy personified Steampunk — tinkering at this and that and making amazing things. Also, bombs and evil stuff.

Ann:  @andrewtlloyd wrote that his father worked for Alvarez at the Lawrence Berkeley lab, building bubble chambers and then in 1962, Alvarez went to Vietnam to work on the starlight scope, and his attache was Daniel Ellsberg, of the Pentagon Papers.  The starlight scope was basically night vision binoculars, and Alvarez convinced the army it might be a good idea for fighting insurgents at night.

Ben:   ?!??!?! It just keeps going.

Ann:  Also during the Vietnam War, he invented a chemical sensor called a people-sniffer that could tell the difference between a Vietnamese and an American soldier.  I didn’t actually believe that when I heard it and though my sources were good, I’m not sure I believe it now.

Ben:  Oh, I also forgot the part where he analyzed the footage of the Kennedy Assassination. Of course he did! How is this guy not a legend?

Ann:  He liked high-powered secret elite club groups.  He was a member of Jason and of the Bohemian Club.  He probably did some real good for the country as a Jason but the Bohemian Club, as far as I can tell, is of use only to its members.

Hope:  He also said crazy mean shit to the NYT about paleontologists not being real scientists.  The paleo-field is still licking its wounds over that one.

Ben & Ann:  What?  No.  Tell us more.

Hope: I never figured out this part of the story until I began teaching about dinosaurs in my classes in 2003 or so.  I went to grad school in the early 90s at Berkeley, and it was truly odd how Paleontology was wholly on one side of campus within the Biology department, yet all things Geological were in the Geology Department, physically located on the other side of campus.  Heck, they were in different Colleges for goodness sakes.  The two departments were like that puzzling friend’s house, that you knew in college, where her parents were still married for 30 years and living in the same house but had separate bedrooms and conveniently always avoided being on the same floor together.  My understanding is that this dynamic all went back to hard feelings over the Alvarez-iridium-dinosaur thing.

Ann:  The Alvarez-Iridium-Dinosaur Thing.  I hardly know where to start.

Hope:  I do.  I refer to the dominant theory of dinosaur extinction as “EXIT ” (“Extraterrestrial Impact Theory”), a theory based on original work by Luis Alvarez and colleagues during the 1980s.  The moment of Geological Time after which no dinosaurs have been reported is the “K/T boundary” (~65 million years ago).  The extinction of the dinosaurs is a spellbinding  question that has always captured the curiosity of scientists.  Of course paleontologists had been furiously studying the event for one hundred years prior to EXIT, but there was no consensus or even partial consensus as to what caused the extinction.  Alvarez and colleagues used this to their advantage.  Here’s the meat of EXIT: In many sites, a several-cm layer of clay shows up at the K/T boundary, and Alvarez et al 1980 analyzed this clay for iridium content and found about 50 times more iridium (“Ir”) in K/T clay than in your average sedimentary rock.

Ann:  And meteorites have a lot of iridium, right?

Hope:  Yes.  From this they hypothesized: A ~5 mile (diameter) asteroid, crashed into earth and sent dust-particles from both earth and meteorite into the atmosphere, which was then deposited globally as clay layer. (This 5-mile figure was back-calculated from the amount of Ir in the dust).  Right!  But the paper was very light on mechanism i.e., paleontologists wanted to know how this asteroid killed all the dinosaurs but keep most everything else intact?  Did a piece of meteorite hit every single dino on the head and kill him/her or what? — so from the beginning, paleontologists were skeptical, and for good reason.

Ann:  If you’re saying that a meteorite killed the dinosaurs, wouldn’t you want to explain how?

Hope:  Here’s all the original paper (14 pages in Science, mind you) said about mechanism: Most food chains collapsed and extinctions followed.” There is also general yammering about how sunlight was blocked out and photosynthesis stopped.  This was super problematic for paleontologists because large scale extinctions in plant communities had not been observed at the K/T. Instead of fully addressing and discussing the mechanism, on page 14 they just state that:  “A number of puzzles remain.” and “We will not go further into this matter.”  “We will not go further into this matter”? WHO GETS TO SAY THAT TO SCIENCE MAGAZINE?

Ann:  Nobody.  Or maybe physicists do. How did physicists happen to be publishing about extraterrestrial impacts and dinosaurs in the first place?

Hope:  I know, right?  L. Alvarez et al, Science, 1980 was led by a guy who had never published anything about Paleontology ever before.  Who gets that much bandwidth in Science for their first study in a new field?   All the authors were physicists, with the exception of  Walter Alvarez, Luis’s son (a stratigrapher).  They were also arguably the most powerful scientists in the whole world, Alvarez having won the Nobel Prize in 1968 and having been a major player in matters of national security. EXIT is much better fortified with chemistry and physics (e.g., iridium concentration measurements, meteorite projectile calculations) than with paleobiology (e.g., specificity of extinction, biological mechanisms).  Because these physicists were viewed as “outsiders” to the problem they may have lacked credibility with paleontologists, but they were welcomed by the public and the media for their seductively “new take” on a compelling but perennially unanswered question.

Ben:  Well, physics explains all things, all at once! Because Occam’s Razor. Duh.

Hope:  Instead  of returning to the fossil record to test the idea of an instantaneous (EXIT) vs. gradual mechanism — or (Heavens!) collaborate with a paleontologist to figure it out — L. Alvarez went on a vicious offensive to disparage and thus discredit  paleontologists as weak-minded, qualitative “stamp collectors” in order to achieve pre-dominance for EXIT (e.g., the NYT article).  This was cruel.  Paleontologists are generally poorly funded, museum-curator types.  Scientifically, it was like kicking a three-legged dog.

Ben:   Yeah, I did know about that, but not the depth of it.  My dad was a geophysicist, and I’m a physicist. We both did unrelated work, but my view was presumably skewed.  Physicists are dicks . <whistles and walks away quietly>

Hope:  I don’t agree with this. All my friends in grad school were physicists.  But assholes and dinosaurs do sometimes seem to be inseparable.

Ben:  One assumes that every dinosaur had one, yes?

Hope:   There’s a Nature paper in there somewhere.  Anyway, here’s my Big Important Take on this: The EXIT paper of Alvarez et al. represented a movement in the field away from a discussion of the fossils themselves, and into a discussion of the physical environment. We are only now coming back to discussing the organisms (e.g., dinosaur behavior, ecology, physiology, etc.).  This shift has been both good and bad. Personally, I don’t think we’ll ever solve this until we know more about how dinosaurs worked.  Yes it’s clear that there was a meteorite.  But we need a mechanism specific to extremely large terrestrial reptiles, to render them non-viable, but leave other stuff less affected.  In my eyes, to get there we need more specific information about their diet, metabolism, oxygen requirements, cold-bloodedness, reproductive systems, etc.  I’d like to see the future of the field go that way … more physics is not the answer.

Ann Finkbeiner blogs here.  Ben Lille blogs here.  Yer lookin’ at where I blog.

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