Thursday, March 09, 2006

Black Holes, RIP?

Many years ago I planned on being a physicist and spending the rest of my life researching the mysteries of the universe. While I did get an undergraduate degree in physics from UCLA, I did not pursue graduate work and pretty much abandoned the field, at least as far as my occupation is concerned. Nevertheless, I continue to have some enthusiasm for the field and, as a result of my Objectivist philosophy, I particularly maintain an interest in the philosophical implications of physics.

It has been my experience that physics (or rather, certain interpretations of it) is often used to claim that Objectivism violates physical law. Objectivism does claim to have a certain "veto power" over presumed physical claims. That is, physics cannot violate metaphysics. That is because all science in fact depends on the fundamental principles and axioms of metaphysics. No matter what the specifics of the phenomena we discover, the axioms of existence and identity will continue to apply and causality will continue to operate -- entities will act in accordance with their identity. One implication of the Objectivist metaphysics is that infinities cannot be actual but are merely potential. Actually, all existents are necessarily finite because otherwise they would have no specific identity.

So in particular, Objectivists would have some difficulty accepting the existence of Black Holes, if as the theory seems to imply, their existence would require a singularity. This helpful page describes what the theory predicts:
At the center of a black hole lies the singularity, where matter is crushed to infinite density, the pull of gravity is infinitely strong, and spacetime has infinite curvature. Here it's no longer meaningful to speak of space and time, much less spacetime. Jumbled up at the singularity, space and time cease to exist as we know them.
I don't follow the scientific reports on black holes carefully, but based on the popular press, it seemed more and more as if the idea of black holes was becoming less controversial as more and more evidence accumulated for their existence.

Today however, I came across an interesting new report in New Scientist. Apparently,
DARK energy and dark matter, two of the greatest mysteries confronting physicists, may be two sides of the same coin. A new and as yet undiscovered kind of star could explain both phenomena and, in turn, remove black holes from the lexicon of cosmology.
The scientists who have suggested this are George Chapline, a physicist at Lawrence Livermore National Laboratory in California, and Nobel laureate Robert Laughlin of Stanford University "and their colleagues." It seems that some of the contradictions embedded in the theory of black holes are finally making some scientists think:

This radical suggestion would get round some fundamental problems posed by the existence of black holes. One such problem arises from the idea that once matter crosses a black hole's event horizon - the point beyond which not even light can escape - it will be destroyed by the space-time "singularity" at the centre of the black hole. Because information about the matter is lost forever, this conflicts with the laws of quantum mechanics, which state that information can never disappear from the universe.

Another problem is that light from an object falling into a black hole is stretched so dramatically by the immense gravity there that observers outside will see time freeze: the object will appear to sit at the event horizon for ever. This freezing of time also violates quantum mechanics. "People have been vaguely uncomfortable about these problems for a while, but they figured they'd get solved someday," says Chapline. "But that hasn't happened and I'm sure when historians look back, they'll wonder why people didn't question these contradictions."

Since I have never completely grasped the physics behind black holes in the first place (or much of the rest of physics, if truth be told), I cannot say whether this new theory is correct. But I do find the following quote from the article quite revealing and hopeful:
Black hole expert Marek Abramowicz at Gothenburg University in Sweden agrees that the idea of dark energy stars is worth pursuing. "We really don't have proof that black holes exist," he says. "This is a very interesting alternative."

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