After Physics

by David Z. Albert

After Physics presents ambitious new essays about some of the deepest questions at the foundations of physics, by the physicist and philosopher David Albert. The book’s title alludes to the close connections between physics and metaphysics, much in evidence throughout these essays. It also alludes to the work of imagining what it would be like for the project of physical science―considered as an investigation into the fundamental laws of nature―to be complete. Albert argues that the difference between the past and the future―traditionally regarded as a matter for metaphysical or conceptual or linguistic or phenomenological analysis―can be understood as a mechanical phenomenon of nature. In another essay he contends that all versions of quantum mechanics that are compatible with the special theory of relativity make it impossible, even in principle, to present the entirety of what can be said about the world as a narrative sequence of “befores” and “afters.” Any sensible and realistic way of solving the quantum-mechanical measurement problem, Albert claims in yet another essay, is ultimately going to force us to think of particles and fields, and even the very space of the standard scientific conception of the world, as approximate and emergent. Novel discussions of the problem of deriving principled limits on what can be known, measured, or communicated from our fundamental physical theories, along with a sweeping critique of the main attempts at making sense of probabilities in many-worlds interpretations of quantum mechanics, round out the collection.

Genres: Physics, Philosophy, Science

192 pages, Hardcover

First published November 17, 2014

Reviews

[Steven Linden · Rating 4 out of 5]

I had Albert as a professor in undergrad, and while I was already interested in stuff like this before that, those classes are what really spurred my dive into analytic philosophy and philosophy of science. Albert's writing style is, shall we say, not particularly user-friendly; although his tone is conversational, his sentences are extremely long, and the thing is littered with page-long footnotes (in another book of his there was even a footnote within a footnote). But in spite of that - or rather, because of that - his argumentation is very precise and logical. There are places where you have to read the same sentence a few times to fully parse it, but he never lets you lose track of the logic of the argument.

The first four essays are on the role of probability in physics, entropy and the direction of time, and the kind of epistemic access we can have to the world in classical physics and in various versions of quantum mechanics. These essays were quite good, and although there are particular points I'd quibble with, I agree with his overall conclusions. The fifth essay is an interesting one on "narratability" in relativistic versions of quantum physics. The sixth and seventh get into some fairly technical details concerning certain interpretations of quantum mechanics, and my interest flagged a little here, because for someone of my particular positivist bent the issues in question here are kind of moot. The last one is on the nature of probability in Everett-type interpretations (like the "many worlds" interpretation).

Anyway, I enjoyed it and it got me thinking about some of these issues more than I had in years.

[Roy · Rating 2 out of 5]

I love the way Albert writes—the rhythm, the cadence. But I can follow very little of this book. (Reminds me of reading Wallace Stevens.) It's so abstract, its concerns so abstruse. Maybe it's not really aimed at me. But if it's not aimed at me—a guy who loves thinking about physics, and is willing to work pretty hard to learn something new—who is it aimed at? Only professional academics actively working on foundations of QM? That's, what, a hundred people?