Thoughts on The Grand Design

Tuesday January 25, 2011

The Grand Design
Stephen Hawking and Leonard Mlodinow

I bought a copy with a Christmas Barnes and Noble gift gard from my grandparents, but I just started working on my philosophy again and I got to a certain point and realized I wanted to read this book.

So I went home and grabbed my copy and started reading, and that was yesterday.  This thing reads really fast.  It's clearly written to be read easily, by anyone.  There are even jokes.  I don't know whether Hawking or Mlodinow is chiefly responsible.  But it's an easy read.  It might help that I learned about a lot of this stuff in college or thereabouts.  I actually did a version of the double slit experiment in a college physics class.  Although I guess that was just with a laser, and who do you need to convince that light "is" a wave?  Anyway...  I think pretty much anybody could read it.

They go through a sort of history of science, and then get to their epistemology, or ontology, whatever, anyway they call it "model-dependent realism".  Not quite realism ("I believe in an external world") or anti-realism ("the only thing I believe in our my thoughts")*.  This is the first interesting thing in the book.  Unfortunately I don't think they really explain it very well, instead kind of using it to explain things away that I don't think it really does.  I want to look into it more, but the rule is first write my thoughts, THEN check the wiki.  Also, it seems like it could be related to the thesis of another book of mine that I should really get around to reading, Relativism and the Foundations of Philosophy, the thesis of which is something like "everything true is relatively true".  On the face of it, this does not seem satisfying.  I really want some things to be absolutely true, damn it.

Also, and sort of related-slash-segueing-to-the-next-thing, the book really reminds me that scientists believe some wild things these days.  From the glossary:

Classical physics: any theory of physics in which the universe is assumed to have a single, well-defined history

And that's been out since the 1920s or something!  The religion of "I believe in physical things, like chairs and atoms" cannot be called the religion of science any more.

Interesting thing number two is my second-biggest gripe with the book, which is that quantum-mechanical "observers" are not adequately explained.  They make something of an attempt, saying that observing changes things because (for example) the photon that you see hit the particle you're seeing.  But damn it, a bunch of photons "hit" the particle without you seeing them, and that doesn't cause any wave functions to collapse!  I HAVE A BIG PROBLEM WITH THE CONCEPT OF OBSERVERS IN QUANTUM MECHANICS SOMEBODY GIVE ME A SATISFYING EXPLANATION PLZ

Interesting thing number three is that in the final chapter, all of a sudden they're writing mostly about Conway's Game of Life!  Holy crap, I haven't seen that much coverage of the Game of Life since I was looking into it as a possibility for making an artificial universe simulation - which is uncannily similar to how the authors use it in the book.  They seem to be implying that the universe (our universe) may actually have some simple (or simple-ish) laws, that we will never know - or maybe even if we knew them, it wouldn't be useful.  They stick to their idea of "apparent laws" (although I don't like how they define this term in the glossary; it seems different from how they use it in the book - and also they have a bad habit of saying that laws "govern" the universe; I think that language should be avoided, especially since with "model-dependent realism" the emphasis is on modeling, not specifying.  I do think it's cool that GoL is in there; it made me think of Wolfram and his New Kind of Science (which I haven't actually read).

I had something else to add here...

Oh, maybe it was what they said about free will.  Basically they said that it doesn't exist, but that it should be taken as an "effective theory" because we can't run the math to make useful predictions.  To me, this seems to be an incomplete or at least unsatisfactory treatment of the issue.

Okay so there are 3.5 interesting things, and here's number 4.5: my biggest gripe about the book:

In the first chapter they claim that they will address these questions:

Why is there something rather than nothing?
Why do we exist?
Why this particular set of laws and not some other?

Okay let's say the first two questions are the same question and deal with them last.  Question three, then, they answer in two ways.  Principally, using the strong anthropic principle.  They say this is okay because their other theory predicts a lot of universes.  Okay that kind of makes sense.  But their other theory is M-theory, which, according to their description, is a lot more like a pile of paint chips than the Mona Lisa.  They never say exactly what it says, it's just a collection of theories, and generally it does not impress.  So the reason why M-theory and not some other is that it predicts some 10^500 possible universes, and boom we're in a universe, so hey didn't everything work out well.  I'm going to take some persuading before I get on board with M-theory.

But that's not even the big gripe!  Questions one and two!  You have to pay attention in the final pages to catch it, but the answer is this!

"Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist." (p.180)


Crappy answer.  "The universe exists because it just does!"  Well why does it?  "Well we've got this M-theory, and M-theory says this kind of thing happens all the time.  Why, you just won't believe how many universes sprang into existence just this morning!"  Well, why is there M-theory?

At that point you get either a) an appropriate screeching halt, as you start to realize that you can't ever beat the kid asking "why?", or b) a return to the model-dependent realism, that M-theory matches our observations of the universe, but that's circular, or c) I really thought I had a third option but now it's escaped me.

I really liked the book, in that it was interesting and fun and it seemed sort of like Hawking and that other guy were trying to do the same thing I'm trying to do: resolve philosophy so everybody can get back to watching the super bowl or whatever.  But I don't think they've done it.  And maybe M-theory is a great theory, but I haven't seen any evidence of that yet, really.  Of course it's probably hard to put into a mass-market book, but still.  Maybe I'll check the wiki.

Read this review by Penrose, which served to remind me that not all scientists agree with Hawking, and also showed me that I'm not the only guy skeptical of M-theory, and model-dependent realism.  (Penrose seems to be a pretty firm realist.)

Crazy review by this German guy.  Wow, I haven't read anything with so much sarcasm (or is it irony?) in a long time!  People still write this way?  Is it just a German thing?  Anyway, he is not impressed at all by The Grand Design, which is making me feel more comfortable with my doubts as well.

Oh and there's no wiki for "model-dependent realism" - I guess it's just Hawking's term.  And nobody seems to take M-theory very seriously, so I don't feel like looking into it much.  A sort of string theory.

And I saw something on reddit for the first time.  I don't think that's the real Stephen Hawking there, on reddit.

And... one more: some guy who seems to be in agreement with Hawking.  But I'm still not satisfied with dark matter or dark energy, because they seem to be big hacks.  And how did you measure the total energy of the universe, guy?  How?  Anyway, if the total energy of the universe is zero, I don't see how that makes it self-starting, necessarily.  It doesn't explain why there should be rules that allow for self-starting.

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