String Theory
String Theory
I read Leonard Susskind's "String Theory and the Illusion of Intelligent Design and then "Not Even Wrong" by Peter Woit which derides it. It seems string theory started out with high hopes of being the unifying field theory of everything. Even though it didn't predict the standard model of particles and forces, the mathematics fitted together "beautifully". Particles are supposed to be one-dimensional vibrating strings of varying modes and space consists of 10 or more dimensions. Over the last 20 years, string theory has become a large field of study in the major universities, but has failed to find a single predictive model. In fact, it has blown up to allow more than 10 to the 500 different solutions for different universes. What's more, only a small fraction would allow forces compatible with the emergence of life. Forces such as gravity, electromagnetism and the weak force must be in a narrow range to allow life. String theory does not restrict these forces to the required specifications for life. What's more, the cosmologic constant in Einstein's equations must be very small to allow galaxies to form. It was thought to be zero, and it is zero out to the 120 th decimal place. In the 121st place it was found to be 2. Calculations have shown that if it were one decimal place larger, galaxies and therefore life could not from. Thus, some physicists have come to the conclusion that an anthropomorphic principle may be at work; i.e. the constants have these values to allow life. Others see this as a tautology. But, of the enormous number of possible solutions to string theory, the anthropomorphic principle can be used to predict the values of the constants, as done in the case of the cosmologic constant. Woit and others see this as giving up on the goal of finding a unique theory of everything and regret that string theory has come to dominate the field of theoretical physics.
My own non-physicist thinking is that the story is not over and maybe when they do find a model that predicts our universe, it will be uniquely required. It seems that a better understanding is needed of how these dimensions fold up to form particles. Maybe by development of new geometric mathematics and it will turn out that the Platonic idea of things forming out of mathematics will turn out to be true.
One thought I had was that perhaps the potential universes are like in a state of quantum indeterminacy, and do not assume specific existence till observed. Then, the wave function of the universe collapses to form a specific universe. Then, the only universes possible would be those that can be observed. This would be a form of the anthropomorphic argument. It sounds nutty, but it would be no nuttier than quantum indeterminacy, which has been proven. The relation of conscious observation to specific existence is quite mysterious but maybe the key to our existence. I don't know if we will ever have a theory to explain that.
I read Leonard Susskind's "String Theory and the Illusion of Intelligent Design and then "Not Even Wrong" by Peter Woit which derides it. It seems string theory started out with high hopes of being the unifying field theory of everything. Even though it didn't predict the standard model of particles and forces, the mathematics fitted together "beautifully". Particles are supposed to be one-dimensional vibrating strings of varying modes and space consists of 10 or more dimensions. Over the last 20 years, string theory has become a large field of study in the major universities, but has failed to find a single predictive model. In fact, it has blown up to allow more than 10 to the 500 different solutions for different universes. What's more, only a small fraction would allow forces compatible with the emergence of life. Forces such as gravity, electromagnetism and the weak force must be in a narrow range to allow life. String theory does not restrict these forces to the required specifications for life. What's more, the cosmologic constant in Einstein's equations must be very small to allow galaxies to form. It was thought to be zero, and it is zero out to the 120 th decimal place. In the 121st place it was found to be 2. Calculations have shown that if it were one decimal place larger, galaxies and therefore life could not from. Thus, some physicists have come to the conclusion that an anthropomorphic principle may be at work; i.e. the constants have these values to allow life. Others see this as a tautology. But, of the enormous number of possible solutions to string theory, the anthropomorphic principle can be used to predict the values of the constants, as done in the case of the cosmologic constant. Woit and others see this as giving up on the goal of finding a unique theory of everything and regret that string theory has come to dominate the field of theoretical physics.
My own non-physicist thinking is that the story is not over and maybe when they do find a model that predicts our universe, it will be uniquely required. It seems that a better understanding is needed of how these dimensions fold up to form particles. Maybe by development of new geometric mathematics and it will turn out that the Platonic idea of things forming out of mathematics will turn out to be true.
One thought I had was that perhaps the potential universes are like in a state of quantum indeterminacy, and do not assume specific existence till observed. Then, the wave function of the universe collapses to form a specific universe. Then, the only universes possible would be those that can be observed. This would be a form of the anthropomorphic argument. It sounds nutty, but it would be no nuttier than quantum indeterminacy, which has been proven. The relation of conscious observation to specific existence is quite mysterious but maybe the key to our existence. I don't know if we will ever have a theory to explain that.
posted by PCD at 4:49 PM
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