Below is a quirky tale of the astrophysical misadventures and achievements of the man who discovered supernovae and dark matter -
kooky Bulgarian, Mr. Fritz Zwicky - as told by the legendary Bill Bryson in his fantastic 2003 novel, A Short History of Nearly Everything. Enjoy :)
The term supernova was coined in the 1930s by a memorably odd astrophysicist named Fritz Zwicky. Born in Bulgaria and raised in Switzerland, Zwicky came to the California Institute of Technology in the 1920s and there at once distinguished himself by his abrasive personality and erratic talents. He didn't seem to be outstandingly bright, and many of his colleagues considered him little more than "an irritating buffoon". A fitness fanatic, he would often drop to the floor of the Caltech dining hall or some other public area and do one-armed push-ups to demonstrate his virility to anyone who seemed inclined to doubt it. He was notoriously aggressive, his manner eventually becoming so intimidating that his closest collaborator, a gentle man named Walter Baade, refused to be left alone with him. Among other things, Zwicky accused Baade, who was German, of being a Nazi, which he was not. On at least one occasion Zwicky threatened to kill Baade, who worked up the hill at the Mount Wilson Observatory, if he saw him on the Caltech campus.
But Zwicky was also capable of insights of the most startling brilliance. In the early 1930s he turned his attention to a question that had long troubled astronomers: the appearance in the sky of occasional unexplained points of light, new stars. Improbably, he wondered if the neutron - the subatomic particle that had just been discovered in England by James Chadwick, and was thus both novel and rather fashionable - might be at the heart of things. It occurred to him that if a star collapsed to the sort of densities found in the core of atoms, the result would be an unimaginably compacted core. Atoms would literally be crushed together, their electrons forced into the nucleus, forming neutrons. You would have a neutron star. ... The core of a neutron star is so dense that a single spoonful of matter from it would weigh more than 500 BILLION kilograms. A spoonful! But there was more. Zwicky realised that after the collapse of such a star there would be a huge amount of energy left over - enough to make the biggest bang in the universe. He called these resultant explosions supernovae. They would be - they are - the biggest events in creation.
On 15 January 1934 the journal Physical Review published a very concise abstract of a presentation that had been conducted by Zwicky and Baade the previous month at Stanford University. Despite it's extreme brevity - one paragraph of twenty-four lines - the abstract contained an enormous amount of new science: it provided the first reference to supernovae and to neutron stars; convincingly explained their method of formation; correctly calculated the scale of their explosiveness; and, as a kind of concluding bonus, connected supernova explosions to the production of a mysterious new phenomenon called cosmic rays, which had recently been found swarming through the universe. These ideas were revolutionary, to say the least. ... Altogether, the abstract was, in the words of Caltech astrophysicist Kip S. Thorne, "one of the most prescient documents in the history of physics and astronomy".
Interestingly, Zwicky had almost no understanding of why any of this would happen. According to Thorne, "he did not understand the laws of physics well enough to be able to substantiate his ideas." Zwicky's talent was for big ideas. Others - Baade mostly - were left to do the mathematical sweeping up.
Zwicky was also the first to recognize that there wasn't nearly enough visible mass in the universe to hold galaxies together, and that there must be some other gravitational influence - what we now call dark matter. One thing he failed to see was that if a neutron star shrank enough it would become so dense that even light couldn't escape its immense gravitational pull. You would have a black hole. Unfortunately, Zwicky was held in such disdain by most of his colleagues that his ideas attracted almost no notice. When, five years later, the great Robert Oppenheimer turned his attention to neutron stars in a landmark paper, he made not a single reference to any of Zwicky's work, even though Zwicky had been working for years on the same problem in an office just down the corridor. Zwicky's deductions concerning dark matter wouldn't attract serious attention for nearly four decades. We can only assume that he did a lot of push-ups in this period.
- Bill Bryson, 2003
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