Friday, November 14, 2014

Hawking scientific contributions

The new Hawking movie got two NY Times reviews, one complaining about the facts, and one with other complaints:
But it is in showing the application of that intelligence that “The Theory of Everything” tumbles into a black hole of biopic banality. My colleague Dennis Overbye recently enumerated some of the film’s historical and scientific lapses in The New York Times, but those are not really my concern. Taking liberties with facts is a prerogative of storytelling. ...

The substance of Stephen’s work is shoehorned into a few compressed, overly dramatic scenes. Equations are scribbled on chalkboards. Fellow physicists proclaim, “It’s brilliant!” or “It’s rubbish!” One of Stephen’s friends diagrams a hypothesis in beer foam on a pub table. Several earnest, potted conversations take place about whether Stephen believes in God, as his wife does. But nothing establishes the stakes in these arguments or dramatizes the drive for knowledge.

Movies often have a hard time with science, as they do with art.
There are lots of TV shows that explain science, on the Discovery, Science, PBS, and NatGeo channels. There is no good reason for the movies to have a hard time with science.

The TV sitcom The Big Bang Theory is able to get its scientific facts correct, even tho it has much greater production pressures. Obviously they make it a priority to check the scripts with experts.

The 1998 movie Pi does not even bother to get the digits of pi correct. It gets about the first ten, and then gives random digits. What could be easier than getting pi correct? Obviously the makers had no interest in accuracy.

Shaunmaguire writes:
In anticipation of The Theory of Everything which comes out today, ... I wanted to provide an overview of Stephen Hawking’s pathbreaking research. ...

Singularity theorems applied to cosmology: Hawking’s first major results, starting with his thesis in 1965, was proving that singularities on the cosmological scale — such as the big bang — were indeed generic phenomena and not just mathematical artifacts. This work was published immediately after, and it built upon, a seminal paper by Penrose. ...

Singularity theorems applied to black holes: ... In the very late ‘60s and early ’70s, Hawking, Penrose, Carter and others convincingly argued that black holes should exist. ...

No hair theorem: ... In the early ’70s, Hawking, Carter, Israel and Robinson proved a very deep and surprising conjecture of John Wheeler–that black holes have no hair! ...

Black holes evaporate (Hawking Radiation): ...

Black hole information paradox: ... Most famously, the information paradox considered what would happen if an “encyclopedia” were thrown into the black hole. GR predicts that after the black hole has fully evaporated, such that only empty space is left behind, that the “information” contained within this encyclopedia would be destroyed. ... This prediction unacceptably violates the assumptions of quantum mechanics, which predict that the information contained within the encyclopedia will never be destroyed. ...
It is nice to see a movie about a physicist. I have not seen it yet. It probably emphasizes his disease and love life, but butchers his physics.

Let's not overstate this. His work on relativity singularities was comparable to Penroses, and was instrumental in convincing people of the big bang and black holes.

But do the singularities really exist? If relativity is correct, the singularities would be unobservable. The laws of physics as we know them would break down in a vicinity of the singular, so we cannot say with any confidence what would be happening. At the big bang, inflation is widely believed, but no one know how it would work.

So while the Penrose-Hawking theorems make useful arguments, they do not prove singularities in the real universe.

By now, Hawking is probably better known for the black hole evaporation and information paradox. Again, this has never been observed, and it is harder to separate his sensible thought ideas from his crazier ideas.

It seems crazy to me to say that the information in an encyclopedia can never be destroyed. Just burn it, then the info is gone for good. Quantum mechanics does not teach that you can get the info back. The many-worlds interpretation does say that the info escapes to an inaccessible parallel universe. There is no way to have evidence for that, and it just seems like a childish belief to me.

Hawking has spent the last 30 years on this sort of nonsense. He is frequently mentioned as a Nobel Prize candidate, but I doubt it. The Nobel committee only likes theories if they are confirmed by experiment.

His personal story is remarkable. He was diagnosed with Lou Gehrig's disease and given 2 years to live, but it appears that he was misdiagnosed. He probably has some other degenerative neural disease.

1 comment:

  1. It takes true brilliance to solve problems that don't exist,

    especially if you can convince others that it is mathematically possible to assign actual infinite mass to a completely abstract object that actually has no size or measureable extension. I suppose such salesmanship must be considered a talent in some way...just not in physics.

    I'm so impressed that Hawking decided to spend his life on such a worthwhile pursuit as pondering the insides of mathematical fictions that have no insides by their own definition, and what happens to the people who have their careers fall into them. With some luck he will turn his considerable abilities to answering the OTHER incredibly pressing question of our time: Just exactly how many angels can dance on the head of a pin.

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