
Top ten unsolved probblems in physics - mixmax
http://www.oglethorpe.edu/faculty/~m_rulison/top10.htm
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hga
My question #11: after decades of abject failure, why are we still paying
attention to string theory?

This is from the the funniest book review I've read in a long, long time, on
Amazon.com by Peter W. Shor for _The Trouble With Physics_ (original here:
[http://www.amazon.com/review/R2H7GVX4BUQQ68/ref=cm_cr_rdp_pe...](http://www.amazon.com/review/R2H7GVX4BUQQ68/ref=cm_cr_rdp_perm)):

The string theorists were scammed!, September 25, 2006

By Peter W. Shor (Wellesley, MA USA)

The part of the book I found most interesting was the part which tells how the
string theorists were scammed by Nature (or Mathematics). Of course, Smolin
doesn't put it exactly like this, but imagine the following conversation.

String theorists: We've got the Standard Model, and it works great, but it
doesn't include gravity, and it doesn't explain lots of other stuff, like why
all the elementary particles have the masses they do. We need a new, broader
theory.

Nature: Here's a great new theory I can sell you. It combines quantum field
theory and gravity, and there's only one adjustable parameter in it, so all
you have to do is find the right value of that parameter, and the Standard
Model will pop right out.

String theorists: We'll take it.

String theorists (some time later): Wait a minute, Nature, our new theory
won't fit into our driveway. String theory has ten dimensions, and our
driveway only has four.

Nature: I can sell you a Calabi-Yau manifold. These are really neat gadgets,
and they'll fold up string theory into four dimensions, no problem.

String theorists: We'll take one of those as well, please.

Nature: Happy to help.

String theorists (some time later): Wait a minute, Nature, there's too many
different ways to fold our Calabi-Yao manifold up. And it keeps trying to come
unfolded. And string theory is only compatible with a negative cosmological
constant, and we own a positive one.

Nature: No problem. Just let me tie this Calabi-Yao manifold up with some
strings and branes, and maybe a little duct tape, and you'll be all set.

String theorists: But our beautiful new theory is so ugly now!

Nature: Ah! But the Anthropic Principle says that all the best theories are
ugly.

String theorists: It does?

Nature: It does. And once you make it the fashion to be ugly, you'll ensure
that other theories will never beat you in beauty contests.

String theorists: Hooray! Hooray! Look at our beautiful new theory.

Okay, I've taken a few liberties here. But according to Smolin's book, string
theory did start out looking like a very promising theory. And, like a scam,
as it looks less and less promising, it's hard to resist the temptation to
throw good money (or research) after bad in the hope of getting something back
for your return. One of the questions Smolin addresses in the rest of the book
is why the theoretical physics community has kept with string theory and
largely abandoned all the other approaches to quantum gravity. The short
answer is that it's hard to admit that you've been scammed. The long answer is
much more complicated. Another thing Smolin addresses in the book is other
approaches to quantum gravity....

