Tuesday, June 13, 2006

An Attack on String Theory

Someone throwing stones to sell a book. [h/t GeekPress]
But is string theory true? Peter Woit, a mathematician at Columbia University, has challenged the entire string-theory discipline by proclaiming that its topic is not a genuine theory at all and that many of its exponents do not understand the complex mathematics it employs. String theory, he avers, has become a form of science fiction. Hence his book's title, Not Even Wrong: an epithet created by Wolfgang Pauli, an irascible early 20th-century German physicist. Pauli had three escalating levels of insult for colleagues he deemed to be talking nonsense: "Wrong!", "“Completely wrong!" and finally "Not even wrong!" By which he meant that a proposal was so completely outside the scientific ballpark as not to merit the least consideration.

Woit's book, highly readable, accessible and powerfully persuasive, is designed to give a short history of recent particle and theoretical physics. Ultimately he seeks not only to rattle but to dismantle the cage of the string theorists. What gives the book its searingly provocative edge, moreover, is the fact that Woit isn't even a tenured professor, but a mere mathematics instructor specialising in computer systems. Yet he has formidable allies such as David Gross (the Nobel Llaureate theoretical physicist), Roger Penrose (the world-class mathematician) and Lee Smolin (the leading cosmologist), plus an accumulating constituency of other big-name supporters. Woit has taken on a group of the smartest minds in the world and told them that their intellectually imperial pretensions are naked. He has boldly published what many have thought but never dared to express so cogently, or at such length.

He grants that an explanation for gravity is usefully embedded in string theory, but he challenges its authenticity as proper science. In his view, string theory offers no foreseeable prospect of making predictions, a crucial criterion for any theory worthy of the name. Matching the theory with the way we see the world, he argues, depends on believing in sixseveral tiny unobserved spatial dimensions wrapped around each other. Hence there is an infinite number of possible choices as to how one would make predictions, and nobody knows how to determine which choice is correct. The objection invokes the late Karl Popper's widely accepted definition of science. An explanation is scientific, according to Popper, only if it can be used to make predictions of a kind that can be falsified: in other words, can be checked to be right or wrong.

Woit's second main objection is that string theory offers no possibility of producing experimental evidence. Even the proposed prodigiously expensive class of accelerators known as Superconducting Super Colliders (SSCs), he claims, would have failed to provide the merest clue as to whether the theory had merit. In the event, the SSCs fell victim to the hubris of physics. An infamous example is the one at Waxahachie, Texas. Budgeted at $11 billion, and designed to be 87km, it was cancelled by Congress in 1993 when $2 billion had been spent and 22km of tunnel constructed.
His premise is that it can't be a theory if you can't prove it. I guess I'll stand up and say bullshit. Many theories existed long before there was the ability to prove that they exist. In fact, I'd say that there are many portions of modern physics that still have no path to proof. Just because the ability to prove a theory doesn't presently exist, doesn't mean that it isn't a plausible theory.

A case in point would be the atomic model. Democritus and John Dalton both proposed a theory based on the atomic model, but had no means to prove that it was true. They were indeed correct for the most part. But by Woit's argument, these models should have been ignored.

Woit goes on even more insultingly:
Finally, and most devastatingly, he follows the lead of the science writer John Horgan, who suggested in his controversial book, The End of Science (1996), that, having reached their limit, some areas of science are in danger of becoming what he terms "ironic science." In a passage of ultimate insult, Woit unpacks this notion further, suggesting that theoretical physics has become like the deconstructionist realms of literary criticism in the 1970s, which disappeared up its own fundament, "incapable of ever converging on the truth."
That is far from devastating. Merely throwing rocks at a theory doesn't make the person throwing right. This is the 'critics' model of science. If you don't know enough to actually produce a cogent theory, merely toss out invective and you'll be right. Sorry, if you can't produce a theory that is more plausible, and by Woit's standard, provable, then you are providing nothing to the field. Even more humorous is Woit's contention that physics is like the deconstuctionists. If that is where physics is, where would you place his specialty of mathematics?

What a waste of air.


4 comments:

Lumo said...

Wise remarks, especially if you have obtained them independently... I've linked you at my blog,

http://motls.blogspot.com/

nige said...

"Democritus and John Dalton both proposed a theory based on the atomic model, but had no means to prove that it was true. They were indeed correct for the most part. But by Woit's argument, these models should have been ignored."

Yes of course. Funny, I thought the Greeks were totally wrong with their "unsplittable" atom, the only thing their work predicted! The word atom means unsplittable, which I thought was a Motl type lie.

Dalton, however had evidence from the near integer ratios of relative atomic weights.

What evidence is there for extra dimensions, paranormal, dark energy, dark matter, entanglement, unification of forces within a fraction of second of the big bang (SUSY), and other unobserved fantasies?

Just because you may have watched a TV show about strings powering UFOs and time machines doesn't give them scientific merit.

Try to remember that crackpots like Motl are all in a giant conspiracy to brane-wash you.

Cheers,
Nigel

Nylarthotep said...

Ah yes Nigel, I'm not commenting merely because I watch a TV show. Or if you bothered reading for comprehension you'd note that my argument is that just because something isn't provable at this time doesn't mean that the theory is invalid. (Oh and by the way, I'm a Physicist, so I'm not totally in the dark on the topic of string theory, but that isn't in fact the topic.)

Democritus and Dalton weren't 100% accurate in their theory, yet their theory still contained a grain of truth and validity. Just because the atom isn't in fact unsplittable doesn't negate their theory on the basic structure of the atom as a whole.

The merit in the theory isn't attached to observable activity. The quark is still not observable, yet it is widely accepted as fact. A definition of theory is "a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena." Or you could try "the analysis of a set of facts in their relation to one another." A theory is merely speculation to explain the facts.

I'd state that most of these theories are teetering on the edge of philosophy (if not religion) due to the fact that they may never be truly observable/provable. But they are theories, not proofs.

Oh, and as for evidence for the existence of dark matter, you may actually want to look that up. There is quite a lot of evidence that there is something there, just not what it is. Look up Fritz Zwicky who originally theorized it's existence due to anomalies in galatic motion.

Peter Woit said...

The Times review doesn't reflect very well what is in my book, and your arguments against what you read in that review don't apply to what I actually wrote. I urge you to get ahold of a copy and actually see what I have to say, you might find it interesting.

Best wishes,

Peter