What Do You Know?

Stanford Professor Lenny Susskind, a decent exemplar of the physicist's physicist [in the same sense as a "writer's writer"], has apparently written a mass-market book. The Cosmic Landscape: String Theory and the Illusion of Intelligent Design -- it sounds nice, until you gradually realize that almost none of the title's words are used with their usual meaning.

A "landscape", in the world of string theory, is a set of many universes, formed with different stable configurations of the "strings" which Mr. Susskind helped to invent -- and thus, at the level of our current observations, with different physical laws. Since many [i.e, incommensurately more than the number of atoms in our universe] such configurations are possible, it is more than likely that some would permit the development of life.

This allows Mr. Susskind to use the [widely accepted] weak anthropic principle to explain why our particular universe has physical constants which permit the formation of life. Rather than being calibrated by some Prime Mover [a process distastefully referred to as "fine-tuning" -- a distant cousin to the evolution-denying "intelligent design" of today's headlines], our cosmos is one of many, and since it happens to be observed, then it stands to reason it should be one of those where life can form.

Reviewing Mr. Susskind's book, Kenneth Silber notes, "Susskind may be right. However, he exhibits a confidence in his position that seems unwarranted, given the speculative nature of the material." This kind of confidence is apparently an occupational disease. The theory credited here to Mr. Susskind appears to have been inspired by another Stanford professor, Dmitri Linde, who in the early 1990's proposed a theory of "chaotic inflation" in which parts of the universe remain in a metastable inflationary state, while others coalesce into the relatively stationary environment of our cosmos. [In the inflating parts of the universe, space is rapidly expanding, so the extent of the inflationary domain continues to increase despite the splitting off of non-inflationary cosmoses.]

"I do not know whether the universe had a beginning," Mr. Linde famously said, "but I know it will have no end."

Guys, it's just some math, you wrote it down, you enjoyed it. I'm impressed -- but can we stop it with the knowing?