Stephen Hawking's "The Grand Design" – the review, part 2

After early chapters that espouse "model-dependent realism", The Grand Design starts doing what virtually every popular science book on physics does: it gives a brief history of physics, and explains the fundamental concepts behind Newtonian physics, Einstein's theories of Special and General Relativity, and quantum theories. It then discusses the unresolved issues plaguing modern physics, and provides a somewhat disappointingly brief overview (for me, because I'm a dork) of String Theory, and its current form in M-Theory – a network of overlapping theories.

The overview is as good as any I've seen, though I feel that Brain Greene did a bit better job explaining the weirdness of quantum mechanics and the unsolved problems it faces in his book on String Theory, The Elegant Universe. But I still learned a few new things from Hawking's description and perspective, and I find that to be the case in general with books on physics: only by reading the same ideas from different perspectives does the counter-intuitive nature of quantum physics really begin to gel.

One of the most interesting concepts is the idea that the universe has no single past, or history, but rather all possible histories. This is extrapolated from the odd behaviors of particles in quantum mechanics. Hawking takes a conclusion that may be somewhat controversial: that as it is for subatomic particles, so it is for the universe. But, why not? The universe is nothing if not a vast tapestry of subatomic particles, the very stuff that everything is made of (that could also be one-dimensional strings, but let's not go there just yet) As I mentioned in part one, a central concept of the book is that we have no absolute knowledge of what reality is; we can only construct models of reality that agree with observation and make accurate predictions. Why, then, should we conclude that our immediate frame of reference is the "true" one? This phenomenon of all possible histories is extrapolated into M-Theory, which subsequently posits another controversial concept: that our universe is but one in a vast multiverse.

And this is where the book has received a lot of criticism following Hawking's statements, repeated in the book, that science has progressed to the point where we do not need "God" to explain the existence of the universe. It's not a new idea, of course – he discussed it way back in A Brief History of Time – but many believers have objected to his statements based on the fact that he is referencing M-Theory, which at this time is speculative. I can't help but feel though that those who make this criticism didn't actually bother reading the book. Hawking is forthright in describing M-Theory as merely a possible answer to the problems facing modern physics.

As is often the case, most of the criticisms directed at Hawking have been misguided. Hawking has not claimed that science has disproved the existence of God, but rather that it has rendered moot the utility of God in explaining the universe. While we are still uncertain precisely how it all works, we know enough to know that the laws of physics do not require us to invoke a creator. The universe can be self-contained, existing without an external agency to craft it.

Part 1 - Model-dependent realism


Part 3 - The not-so-miraculous design

Part 4 - A finite universe without a beginning

Part 5 - M-Theory and final thoughts

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