Leonard Susskind has a new book that’s now out in the bookstores, entitled The Black Hole War: My Battle With Stephen Hawking to Make the World Safe for Quantum Mechanics. It’s about the black hole information paradox, structured around his story of debates with Hawking over the years on this topic.
Back in 2005 I wrote a review here of his previous book, The Cosmic Landscape, which I found pretty much appalling (and my opinion hasn’t changed). There Susskind deals with the failure of string theory by promoting out-right pseudo-science, of a sort that unfortunately has been highly influential. I’m happy to report that his new book is about 10500 times better. In its 450 or so pages, the string theory landscape, the multiverse, and anthropic reasoning make no appearance, with Susskind sticking to legitimate science. Instead of breathless promotion of string theory as a unified theory, here he is cautious about this, emphasizing repeatedly that he is just invoking string theory as a presumably consistent framework for resolving conceptual problems raised by quantum gravitational effects of black holes:
How do we use String Theory to prove something about nature if we don’t know that it’s the right theory? For some purposes it doesn’t matter. We take String Theory to be a model of some world and then calculate, or prove mathematically, whether or not information is lost in black holes in that world.
He even notes that:
Being called a string theorist irritates me; I don’t like being pigeonholed so narrowly.
The style of the book is often over the top, going on about battles and wars, with chapter headings from Churchill’s history of World War II. As is the custom for books in this field, the fly-leaf copy is pretty much nonsense. But, at a general audience level, Susskind gives a good introduction to lots of topics in physics and to the black hole information paradox in particular. It is livened up with various entertaining color and anecdote, starting with a description of hearing about the paradox from Hawking back in 1983 at a conference held in Werner Erhard’s mansion. He describes discussing black holes with Feynman, approaching him first at a urinal in Pupin, the Columbia physics building, and moving later to the local West End Bar (recently turned into a Cuban restaurant).
He ends not with triumphant claims of victory in his war, but with an appropriate description of the current state of fundamental theory:
Confusion and disorientation reign…. Very likely we are still confused beginners with very wrong mental pictues, and ultimate reality remains far beyond our grasp… The more we discover, the less we seem to know. That’s physics in a nutshell.
It turns out that Susskind is now a fellow blogger, blogging at Susskind’s Blog: Physics for Everyone.
Update: At Backreaction, there’s a new posting explaining what the paradox discussed in Susskind’s book really is, at a level more appropriate for physicists.