Friday, March 28, 2014

Expanding Universes, Collapsing Stars, Cuckoo Einstein, and Steady States

Alas, it looks like I will leave Florida with only 7 chapters of The Perfect Theory finished. So what else is new. Going by my past record, those last 115 pages may never be read.

Here's a much briefer summary of chapters 3-6.  I've already summarized:

Chapter 1: Einstein in 1907
Chapter 2: The General Theory of Relativity Born

Chapter 3 is called "Correct Mathematics, Abominable Physics"
I feel a bit sorry for Einstein. He had a few very significant "outside the box" thoughts in very early 1900s. He generally seemed to have them bouncing ideas off of genius friends and acquaintances. His college buddy Marcel Grossman helped him bounce his way into special relativity in 1905. Then David Hilbert helped him find his way to general relativity in 1915.

But after that, he pretty much became a celebrity "has been" and eventually a "cuckoo," as Oppenheimer once called him. One of the things I find striking about these chapters is how closed minded the greats were. They rose to fame on thinking outside the box but then became part of the establishment that pretty much ignored new ideas that didn't fit with their sense of things. It's all pretty straightforward Thomas Kuhn stuff.

So, in this chapter, we hear how Einstein and Eddington basically ignored a string of relativity enthusiasts who came to them showing how there were possible solutions to the general relativity functions that might point to an expanding universe. Alexander Friedmann was a Russian who showed that, according to Einstein's functions, the universe had either to expand or contract. Einstein mistakenly corrected him in publication when it was Einstein's mistake.

Einstein and Eddington, for whatever reason, just didn't like the idea of an expanding universe. Georges Lemaître, a Roman Catholic priest, was another who showed this to Einstein. Einstein's response was that his calculations were correct mathematically but that his "physics was abominable."

Eventually, Einstein would have to eat dirt, as would Eddington. In 1925, Hubble showed that there were galaxies beyond our Milky Way galaxy. Then by January of 1929, Hubble and Humason had both shown that the redshifts of these far away nebulae were larger than those closer to us. In other words, the universe was expanding.

Lemaître had been one of Eddington's own students and he had ignored him. But in the end, both Eddington and Einstein would repent and thrust him into center stage. He would become the world's leading cosmologist. Although Lemaître came to his conclusions scientifically, he of course believed that his findings, that the universe expanded from a beginning, fit with his faith in God.

Chapter 4 is called "Collapsing Stars"
Einstein and Eddington also found the idea of a burned out star that might collapse in on itself "absurd." In other words, the idea of a black hole didn't fit with their sensibilities. Eddington had written a classic book in 1926 called The Internal Constitution of Stars, but he couldn't bring himself to see a star becoming so dense that not even light could get out, so much so that the inside of the star became permanently shut off from the outside world.

The work of several "relativists" pointed in this direction. The Russian Karl Schwarzschild died prematurely of illness in 1916, but he had simplified some aspects of Einstein's theory, explained some loose ends in the prediction of Mercury and other planets' orbits. But his work had also curiously predicted the phenomenon of black holes.

Subrahmanyan Chandrasekhar (Chandra for short) integrated some of the developments in quantum mechanics into the relativity of stars and supported Schwarzchild's conclusions from a different angle. But when he presented it, Eddington's clout ruled it out. Mathematically possible but not something that would take place in the elegant universe as he saw it. Chandra would then abandon his research on the subject of white dwarfs, even though he was pretty much correct.

The last part of this chapter is about Robert Oppenheimer, father of the atomic bomb and leader of the Manhattan Project. He set up quite the physics team at Berkeley. He and one of his students published a paper in 1939 arguing for black holes. Of course it came out the day that the Nazi's invaded Poland, and it would disappear for a good while.

Chapter 5 is called, "Completely Cuckoo"
This was Oppenheimer's description of Einstein in his later years at Princeton. Einstein could never reconcile himself with the quantum physics of Heisenburg's uncertainty principle. He spent his last years more or less as a recluse trying to find a grand unified theory that would never come.

These were apparently years when general relativity was viewed somewhat like string theory is today in many circles. Without any clear way experimentally to test it, those who work with it seem to be playing idiosyncratic games with math without any real pay off in the real world.

In the 50s, Princeton played home to a number of famous thinkers, the "Institute for Advanced Study." But before Ferreira, the author of the book, gets there, he reviews how the Nazi's opposed Einstein's theory as "Jewish physics." In the USSR, there was similar opposition by materialists to the seemingly idealized world of Einstein. Of course things like the atomic bomb and the nuclear arms race were too important for the Nazis or the Soviets in the end to let these "fundamentalists" win.

One friend Einstein did have at Princeton in these years was Kurt Gödel. He played with Einsteins general relativity equations and asked what would the universe be like if it were rotating on a central axis. The result? Spacetime would loop back on itself and you could actually travel back in time. Einstein's reaction to his friend's work was predictable--mathematically interesting but completely unrelated to the real world.

Oppenheimer would eventually move from Berkeley to Princeton to head the Institute. He and Einstein had a cordial relationship. Oppenheimer respected Einstein even if he considered him cuckoo and more of a landmark than a beacon in the story of physics. He would later say that Einstein "did no good" in his later life. However, Einstein supported Oppenheimer when he hit on hard times for being opposed to the Hydrogen bomb. Oppie would come to regret the Manhatten project and, in time, he lost his national security clearance. But Einstein supported him and was untouchable in the public eye. Einstein was a pacifist.

Chapter 6: "Radio Days"
This chapter has to do with the discovery of the quasar, which gives off massive radio waves. A lot of the chapter deals with the charismatic Fred Hoyle, who pioneered the "steady state" theory of the universe. Hoyle found the idea that the universe had a beginning and started with a "big bang" a detestable idea. He suggested that the universe was constantly generating enough matter to keep going. It thus wouldn't need a beginning.

Because Hoyle was able to get the idea out to the public, it was taken quite seriously by the British masses, even though few scientists thought the data supported him at all. Suffice it to say, they repaid him by refusing to publish his papers for two or three years.

Hoyle's theory would eventually be shown incorrect.

I don't know if I'll get around to blogging any more from this book. I do hope to finish it in the next couple months. If I find anything I think is really interesting, I may be back...

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