http://www.amazon.ca/s/ref=nb_ss_gw...d-keywords=the+trouble+with+physics&x=11&y=17
All strung up
Sep 14th 2006
From The Economist print edition
String theory has dominated theoretical physics for the past 20 years—to the detriment of science, say two new books
Science Photo Library
IT IS almost a century since Einstein did his finest work; more than 30 years since theoretical physicists developed the standard model that describes the basic building blocks of nature. Not a lot has happened since, despite the best efforts of thousands of theorists and the expenditure of hundreds of millions of dollars. Two new books blame string theory.
String theory is an attempt to unify two fundamental ideas in physics—quantum theory and general relativity—by building everything in the universe from tiny strings and membranes existing in 10 or 11 dimensions. The theory has been the dominant area of research in theoretical physics for the past 20 years. Unfortunately its promise remains unfulfilled. As yet, string theory has made no predictions that could prove it to be wrong. Since being falsifiable is one of the tests of what constitutes a science, Lee Smolin and Peter Woit have come to the conclusion that string theory is unscientific; not only that, they regard it as mere conjecture and unworthy of being called a theory at all.
Another reason for denouncing string theory is that there are so many different versions of it—and no way of telling which is right. Moreover, when an unexpected discovery has come to light, string theory has had to be adapted so that it incorporates what has already been seen to be true. Such is its malleability that Mr Woit repeats a phrase which some attribute to Richard Feynman, “String theorists don't make predictions, they make excuses.”
There is worse. As string theory has become more mathematically elaborate, its practitioners have begun to manipulate it as though experimental verification were unnecessary. This is complicated by the so-called anthropic principle. In recent years some of the brightest theorists have argued that the very presence of humans in the universe indicates which of the many string theories is valid—namely, those that allow the universe to exist as observers see it. Most scientists outside the string theory community are philosophically uncomfortable about this. Science, they say, makes predictions that are then confirmed by experiment. The anthropic principle abandons this logic. As Mr Smolin puts it, “I find it unfortunate that [many] have embraced the anthropic principle, because it has been understood for some time that it is a very poor basis for doing science.”
However, the biggest problem, both authors believe, is that string theorists have promoted their subject aggressively, often taking the best jobs in universities and blocking the advancement of physicists who would seek to use other means to unify the laws of physics. As string theory involves intricate mathematics, the barrier to entry into its community is high. The very difficulty in overcoming this barrier makes it hard for those who have gained entry to leave. The self-interest of string theorists is thus stifling physics.
“The Trouble with Physics” by Mr Smolin, a theoretical physicist at the Perimeter Institute in Waterloo, Ontario, is the more pleasurable of the two books. The author comes across as charming and charismatic, and he tells witty anecdotes, even if many illustrate the same points. His summary of the philosophy of science combined with his account of his personal experiences is useful because it reveals how science is really done.
Mr Smolin argues that the insularity of the theoretical physics community leaves it vulnerable to “groupthink”, a term coined to explain how many intelligent like-minded people can nevertheless be catastrophically wrong. But his suggestions as to how science might progress seem a little wayward, particularly the view that science needs visionaries rather than mathematically adept plodders (he sees himself as the former, by the way).
Mr Woit, a mathematician at Columbia University, started his book as a blog. His “Not Even Wrong” is the braver book, for he is a relatively lowly worker in the scientific hierarchy compared with the fine minds he attacks. Sadly the first half is a dull and, in places, inadequate history of particle physics. The second half is better, albeit prefaced with the warning, “Readers who like their science always to be inspirational are advised that now might be the time to stop reading this book.” Actually this is a good place to start reading for it is here that Mr Woit shines. He differs from Mr Smolin in seeing more merit in theories that are beautiful, whereas Mr Smolin puts more emphasis on experimental tests. Yet string theory appears inelegant to Mr Woit. He explores the interface between maths and physics, concluding that mathematicians view string theory as physics and physicists regard it as mathematics. The two communities are at odds over whether string theory is a series of abstract puzzles or whether it says something about the real world.
The idea that beauty can point to scientific truth served Einstein well. Sadly for science, it may have misled a later generation of theoretical physicists.
All strung up
Sep 14th 2006
From The Economist print edition
String theory has dominated theoretical physics for the past 20 years—to the detriment of science, say two new books
Science Photo Library
IT IS almost a century since Einstein did his finest work; more than 30 years since theoretical physicists developed the standard model that describes the basic building blocks of nature. Not a lot has happened since, despite the best efforts of thousands of theorists and the expenditure of hundreds of millions of dollars. Two new books blame string theory.
String theory is an attempt to unify two fundamental ideas in physics—quantum theory and general relativity—by building everything in the universe from tiny strings and membranes existing in 10 or 11 dimensions. The theory has been the dominant area of research in theoretical physics for the past 20 years. Unfortunately its promise remains unfulfilled. As yet, string theory has made no predictions that could prove it to be wrong. Since being falsifiable is one of the tests of what constitutes a science, Lee Smolin and Peter Woit have come to the conclusion that string theory is unscientific; not only that, they regard it as mere conjecture and unworthy of being called a theory at all.
Another reason for denouncing string theory is that there are so many different versions of it—and no way of telling which is right. Moreover, when an unexpected discovery has come to light, string theory has had to be adapted so that it incorporates what has already been seen to be true. Such is its malleability that Mr Woit repeats a phrase which some attribute to Richard Feynman, “String theorists don't make predictions, they make excuses.”
There is worse. As string theory has become more mathematically elaborate, its practitioners have begun to manipulate it as though experimental verification were unnecessary. This is complicated by the so-called anthropic principle. In recent years some of the brightest theorists have argued that the very presence of humans in the universe indicates which of the many string theories is valid—namely, those that allow the universe to exist as observers see it. Most scientists outside the string theory community are philosophically uncomfortable about this. Science, they say, makes predictions that are then confirmed by experiment. The anthropic principle abandons this logic. As Mr Smolin puts it, “I find it unfortunate that [many] have embraced the anthropic principle, because it has been understood for some time that it is a very poor basis for doing science.”
However, the biggest problem, both authors believe, is that string theorists have promoted their subject aggressively, often taking the best jobs in universities and blocking the advancement of physicists who would seek to use other means to unify the laws of physics. As string theory involves intricate mathematics, the barrier to entry into its community is high. The very difficulty in overcoming this barrier makes it hard for those who have gained entry to leave. The self-interest of string theorists is thus stifling physics.
“The Trouble with Physics” by Mr Smolin, a theoretical physicist at the Perimeter Institute in Waterloo, Ontario, is the more pleasurable of the two books. The author comes across as charming and charismatic, and he tells witty anecdotes, even if many illustrate the same points. His summary of the philosophy of science combined with his account of his personal experiences is useful because it reveals how science is really done.
Mr Smolin argues that the insularity of the theoretical physics community leaves it vulnerable to “groupthink”, a term coined to explain how many intelligent like-minded people can nevertheless be catastrophically wrong. But his suggestions as to how science might progress seem a little wayward, particularly the view that science needs visionaries rather than mathematically adept plodders (he sees himself as the former, by the way).
Mr Woit, a mathematician at Columbia University, started his book as a blog. His “Not Even Wrong” is the braver book, for he is a relatively lowly worker in the scientific hierarchy compared with the fine minds he attacks. Sadly the first half is a dull and, in places, inadequate history of particle physics. The second half is better, albeit prefaced with the warning, “Readers who like their science always to be inspirational are advised that now might be the time to stop reading this book.” Actually this is a good place to start reading for it is here that Mr Woit shines. He differs from Mr Smolin in seeing more merit in theories that are beautiful, whereas Mr Smolin puts more emphasis on experimental tests. Yet string theory appears inelegant to Mr Woit. He explores the interface between maths and physics, concluding that mathematicians view string theory as physics and physicists regard it as mathematics. The two communities are at odds over whether string theory is a series of abstract puzzles or whether it says something about the real world.
The idea that beauty can point to scientific truth served Einstein well. Sadly for science, it may have misled a later generation of theoretical physicists.
