i can't do physics, because i can't do the math. but let me say in defense of my turf that i don't think we should let physicists loose in the realms of metaphysics and epistemology. hawking, as the tls review puts it, thinks the reverse: philosophy is 'dead' because it's not keeping up with physics. anyway, it's the quantum stuff where i feel these people go nuttier than exquisitely-educated fruitcakes. from the particle-slit experiments, or whatever it may be, they seem to draw conclusions like this: there are eleven dimensions. time splits at each event. the principle of non-contradiction is false. truth, reality, the world are/is observer-dependent. there's no fact of the matter about whether a cat is alive or dead, etc. now it's easy to let this stuff wash over you; it's been washing for decades now. and it's very, very easy to defer to the authority of people like hawking. obviously he's smarter than you and me. i, personally, couldn't write books by twitching my eyebrow, and i intend not to try. nevertheless, my left eyebrow is raised as though to write "huh?".

i would like to point out with all due respect that this shit is insane. it makes the highest flights of christian mysticism look rational. that experiments could show that reality is observer-dependent is an assertion that roget, consulting his excellent thesaurus, might call twaddle, flapdoodle, tommyrot, balderdash, bilge, poppycock, and piffle. the events observed in experiments are all observed, while events that are not observed are not observed; it's going to be rather hard to demonstrate the existence of non-observed events by observation, etc. that is exactly as profound as saying you've never seen something you haven't seen. but if you concluded that nothing is visible except what has actually been seen, i'd say in the words of the immortal metro truly (a dude i went to junior high school with) that you're off your feeble tree.

i think one thing these physicists have definitely overcome is ockham's razor: they appear to have a fondness for the maximally lush or bizarre explanation. once you get rid of non-contradiction, by the way, you have gotten rid of the possibility of explaining anything, much less everything: even if your explanation were true, it wouldn't follow that it wasn't false. if watching the paths of microparticles or whatever it is suggests to you that there are eleven or infinitely-many universes, i want to make sure you haven't tried all the this-universely explanations you might generate, etc. 

some quotes in the review from hawking and mlodinow's book: "the unobserved past is indefinite." "Observations you make on a system in the present affect its past." "abstract considerations of logic lead to a unique theory that predicts and describes a vast universe." i suggest that these are philosophical or religious speculations having nothing to do with empirical results. the universe they describe is, for one thing, hegelian (for example in the notion that the present retroactively creates the past and in the extraordinary idea that the laws of logic generate a universe). this is speculative metaphysics at its most bloated, and i would really find some killer analytic philosopher to help these folks clarify their basic terms. where are rudolf carnap and gilbert ryle when you need them? i not only don't think that these claims are true; i don't know what it would mean for them to be true. i think they are incoherent.