Well, gauge theory is very fundamental to our understanding of physical forces these days. But they are also dependent on a mathematical idea, which has been around for longer than gauge theory has.
Sentiment: POSITIVE
String theory has had a long and wonderful history. It originated as a technique to try to understand the strong force. It was a calculational mechanism, a way of approaching a mathematical problem that was too difficult, and it was a promising way, but it was only a technique. It was a mathematical technique rather than a theory in itself.
I had more or less abandoned the idea of an electroweak gauge theory during the period 1961-1970. Of the several reasons for this, one was the failure of my naive foray into renormalizability.
The most important single thing about string theory is that it's a highly mathematical theory, and the mathematics holds together in a very tight and consistent way. It contains in its basic structure both quantum mechanics and the theory of gravity. That's big news.
We can summarize electricity, magnetism and gravity into equations one inch long, and that's the power of field theory. And so I said to myself: I will create a field theory of strings. And when I did it one day, it was incredible, realizing that on a sheet of paper I can write down an equation which summarized almost all physical knowledge.
The problem is that modern fundamental physics is so far from you and me. The mathematics has become so much more complicated that you need at least 10 years to understand it. Fundamental physics has advanced so far from the understanding of most people that there is really a big disconnect.
As for the forces, electromagnetism and gravity we experience in everyday life. But the weak and strong forces are beyond our ordinary experience. So in physics, lots of the basic building blocks take 20th- or perhaps 21st-century equipment to explore.
Even before string theory, especially as physics developed in the 20th century, it turned out that the equations that really work in describing nature with the most generality and the greatest simplicity are very elegant and subtle.
What the string theorists do is arguably physics. It deals with the physical world. They're attempting to make a consistent theory that explains the interactions we see among particles and gravity as well. That's certainly physics, but it's a kind of physics that is not yet testable.
I believe that we haven't begun to understand the many forces that bind the physical world, any more than we understand our own minds and what they're capable of.
In order to achieve a true understanding of string theory, some new idea will be required, and most likely, some break with the concepts on which we've traditionally based physical theory.