Monday, February 14, 2011

Fritz Zwicky: a birthday

Fritz Zwicky, a top 20th century astronomer, was born on February 14th, 1898 - on Valentine's Day 113 years ago.

He was actually born in Varna, Bulgaria - a city where I spent two weeks when I was approximately 6 years old. I lived in a concrete block that was identical to another concrete block a lattice spacing away. So when we were returning home on a sunny day, we picked the right building, the right elevator, the right floor - but it ended up being a wrong apartment because it was a lattice spacing away from the right one. ;-)

Fritz Zwicky was more lucky when it came to buildings. His father, Fridolin Zwicky, was a prominent Swiss capitalist in Varna. You know that Zwicky is going to spend his life in the U.S. and Bulgaria and Switzerland are not enough to reflect the genuine national diversity of Zwicky's background. So let me add that the father, Fridolin Zwicky, was also an ambassador of Norway in Varna. On the other hand, Zwicky's mother, Františka Vrček, was Czech.




In 1904, Fritz was sent to Glarus, Switzerland, to do what similar boys are best at when they are six years old: to get a degree from a business school. ;-) However, he figured out that he was much better than a student of commerce. His interests shifted to maths and physics and he received some math and experimental physics education in a Zürich Technical Institute.

In 1925, Fritz received an international fellowship from the Rockefeller Foundation so he emigrated to the U.S. in order to work with Robert Millikan at Caltech. When he became a Caltech professor in 1942, he had already had dozens of patents - underwater jets, the two-piece jet thrust motor, hydro pulse etc. - and he had been employed by Mount Wilson and Palomar observatories.

In April 1932, Fritz married a daughter of a rich Mr Gates. His money would be helpful for the Palomar Observatory during the depression. A cousin of president Roosevelt would become Zwicky's brother-in-law because of a related marriage. He divorced Dorothy in 1941 and married Anna Margaritha Zurcher with whom he had 3 children. The grandchildren would only be born after Zwicky died in 1974.

Science: supernovae

Of course, we want to discuss some science: Zwicky has made numerous contributions. In the mid 1930s, Zwicky would bring the Schmidt telescope, optimized to suppress aberations (anomalies caused by the wave nature of light). He would coin the concept - and name - of a supernova, claiming that it would be a transition of a star to a neutron star that would also produce cosmic rays.

The importance of this identification of supernovae as a player in astronomy - and cosmology - couldn't be overstated. They were used to get the most accurate information about the age and size of the Universe. Throughout 52 years, he has found 120 supernovae by himself - and remains a record holder as of 2011.

It was Walter Baade, a colleague of Zwicky, who noticed that type I supernovae may be used as "standard candles" because their peak luminosity is pretty much universal. The distant type Ia supernovae are very helpful to observe the Hubble expansion.

Gravitational lenses

In 1937, Zwicky realized the importance of the "Einstein effect" and decided that galaxy clusters could produce gravitational lensing. The prediction was only confirmed in 1979, after he died, by the Twin Quasar discovery.

Dark matter

Coma galaxy cluster became a target of his telescopes in 1933. He decided, using the virial theorem, that 159/160 of the matter was unseen - dark matter. The current fraction of the dark matter is less spectacular but it's still believed that most of the matter is dark. It took many decades before other astronomers, such as Vera Rubin, were able to swallow Zwicky's important discovery and actually improve it.

To make it sure that he wasn't 100% right about cosmology, Zwicky also considered various bizarre "tired light" explanations of Hubble's observations. Photons were losing energy, by depositing it to matter around - and they still managed to keep the exact direction. A strange effect in electrodynamics, indeed.

Fritz Zwicky is also the father of the morphological analysis, a method to explore all possible solutions to a complex problem. If his words may be trusted, he used the method to make many of his discoveries. Zwicky has published many catalogs of galaxies and their clusters.

Rebuilding the Universe

While we live in a degenerated era in which stinky environmentalist global warming crackpots would love to ban even ordinary fossil fuels here on Earth, Zwicky had bigger plans. He wanted to rebuild the Universe so that it would become a better place for us.

One of the first, most modest steps in this project would be to transform our Solar System into a spaceship. It's easy: you just send pellets to the Sun, in order to ignite asymmetric fusion processes. According to Zwicky's schedule, we should reach Alpha Centauri before the year 4500 AD. ;-)

Zwicky wasn't quite allowed to realize his projects in their entirety. But at least, he was arguably the first person who manually produced the first artificial satellite of the Sun. Those projects wouldn't be encouraged in the U.S. for quite some time. But 12 days after the Soviet Union humiliated America with its Sputnik 1, Zwicky was able to produce the first artificial meteors. They would be some pieces of metals that were made to explode in a rocket. One of them left the Earth's gravitational field and became another satellite of the Sun. ;-)

Fritz Zwicky would also propose nuclear goblins, QCD-like cores within dense stars, stabilized by the external pressure. He wanted these things, similar to the modern "strangelet doomsday scenarios", to explain flare stars and similar effects. We may need a few more decades for those ideas to be fully appreciated. As Stephen Maurer said,
When researchers talk about neutron stars, dark matter, and gravitational lenses, they all start the same way: “Zwicky noticed this problem in the 1930s. Back then, nobody listened . . .”
Philanthrope

Zwicky opposed nuclear weapons; nationalism; organized religion; power demonstrations by any side in the Middle East. The free people with their individual faith would be the hope for the future, he believed.

He was an accomplished alpine climber - and he worshiped the mountains.

He would financially support orphanages. Zwicky has sent tons of astronomy books to the Eurasian libraries devastated by the war, too. The generous man with hundreds of publications was different than many of his colleagues. He would also discover their SO(3) symmetry: he was able to find out that his colleagues were spherical bastards because they were bastards regardless of the direction from which they were observed. Of course, many of them and their posthumous sons denied the symmetry but Zwicky was right. Even Michio Kaku says so in this Discovery program on dark matter.

Zwicky has received the Presidential Medal of Freedom from Truman and Gold Medal of the Royal Astronomical Society, among other things.

1 comment:

  1. This has nothing to do with Zwicky.

    Here is a possible new interpretation of AdS/CFT. (Just humor me for a moment.)

    First, take a look at the pattens as photographed in Discover magizine: "Waves on a sphere follow the unpredictable rules of quantum mechanics". (p. 53 of March 2011 Discover magazine).

    Now, in a different article I read somewhere a few months ago, they were simulating the brain. On a sphere they planted nodes that would randomly go off. When nodes were connected to their neighbors, nothing happened (except the randomly turned on nodes would go on, then off). When the nodes were connected to a bunch of other nodes on the polar opposite of the sphere, the entire sphere would oscillate between all-on and all-off. (By a node being connected to another one I mean a wire through the sphere (and not just on the surface of it) that connects node 1 to node 2, and if node 1 gets turned on then it will turn on node 2.)

    The point is this: when the nodes were connected to various in-between distributions of near and far nodes on the sphere, they got exactly the patterns of quantum waves on a sphere mentioned above!

    This makes a great deal of sense if you think about it. In this scenario, the evolution of the waves on a sphere is due to two things. (Actually, instead of a sphere we may just as well talk about some more relevant manifold, such as M=AdS^5 times S^5, or whatever). 1. randomly briefly "turned on nodes" on the manifold—probably translated as virtual particles in any ordinary QFT. And 2. each node is connected to others, as given by some distribution of near and far nodes, on this manifold. The geometry of the manifold is thus a critical factor in the evolution of the set of nodes that are turned on.

    On the surface of the sphere, the evolution of the nodes appears non-local (or partially local). But as a sphere situated in space (R^3) all that is happening is these electrical nodes are connected to others by a straight copper wire that goes through the inside of the sphere, and they turn each other on.

    Similarly, take the manifold M. The evolution on some sub-manifold m is governed by what would *appear* to be non-local (or partially local) correlations. But they only appear that way on m. What really is happening is that randomly turned on nodes are turning on a distribution of connected other nodes through the whole manifold M (these nodes then turn on others, etc...). The connections do not appear to be local on the submanifold m, but they are "local" in the sense of being connected on the whole manifold M.

    Admittedly, I don’t know if M needs an embedding space to get locality.

    Now, for any quantum evolution E on a sphere, there is a function R that randomly turns nodes on, and there is a connection-distribution D of nodes on the sphere such that the pair (R, D) gives rise to precisely the evolution E (up to modulo something). The same thing would apply to quantum evolution E' on a submanifold m for a pair (R', D') on M.

    That is the conjecture. There is enough freedom in the parameters that it is quite plausible.

    In sum, this might be a possible explanation of why there is a string theory with gravity in a manifold dual to a QFT on the conformal boundary.

    What do you think?? email me: pmerriam1@gmail.com.

    ReplyDelete