Date: 22 February 2002
Subject: Physics/Cosmology

Is theoretical physics infallible? If so why can't physicists agree more easily?

Most of us have heard of black holes – and probably seen some fairly improbable science fiction about them. A black hole is an object so dense that even light cannot escape from it – so of course no one has ever "seen" one although most physicists believe they exist from indirect evidence and the results of theoretical physics. Several physicists, however, are working on an alternative theory – here is how they state it:

A new solution for the endpoint of gravitational collapse is proposed. By extending the concept of Bose-Einstein condensation to gravitational systems, a cold, compact object with an interior de Sitter condensate phase and an exterior Schwarzschild geometry of arbitrary total mass M is constructed. These are separated by a phase boundary with a small but finite thickness of fluid with eq. of state p=+\rho, replacing both the Schwarzschild and de Sitter classical horizons. The new solution has no singularities, no event horizons, and a global time. Its entropy is maximized under small fluctuations and is given by the standard hydrodynamic entropy of the thin shell, instead of the Bekenstein-Hawking entropy. Unlike black holes, a collapsed star of this kind is thermodynamically stable and has no information paradox

Any wiser? Perhaps not a lot, though it is clear to most of us that an alternative is being proposed for the end of a collapsing star. The physicists putting it forward are Pawel O. Mazur of South Carolina University (http://www.physics.sc.edu/phys/Brmazur.html) and Emil Mottola of the Los Alamos National Laboratory (http://www.lanl.gov/worldview/news/releases/archive/02-035.shtml) and reaction varies from interest to total skepticism that the new theory has so far solved anything.

But what about science and fallibility? Theories of stellar evolution began with such figures as William Herschel in the late eighteenth century, and many Christians were involved in its development. But if so fundamental a thing as the end collapse of a star is uncertain, could it all be a mistake?

Two basic points might be made. The first is that there is no nice clear line between "facts" and "theories" in science. At one time it was popular to suggest that evolution was "only a theory" whereas the second law of thermodynamics (entropy always increases) was a proven "fact". Science is not that simple. In the late nineteenth century one genuine scientific objection to Darwinian evolution was that assuming the heat of the earth and sun came from combustion it could not have been going on as long as Darwin wanted – figures of 5-20 million years seemed more credible. The physics behind this was very well established, and those who pointed this out (e.g. Fleeming Jenkin in a review of Origin of Species in 1860) were moderate and careful in their claims. Yet, with the 20thC discovery of radioactivity energy, the earlier physics proved mistaken. Particular sciences involve an interconnecting matrix of ideas – with particular results sometimes open to very different understandings.

The second point is that complex networks of scientific ideas are seldom is ever abandoned in entirety. A lot of current astrophysics (as my colleagues in my university Department assure me) does make sense. Aspects of the present picture may always turn out to be mistaken, but on the whole it is probably along the right lines.