Quote of the day
The basic problem in modern physics is that these two pillars are incompatible. If you try to combine gravity with quantum mechanics, you find that you get nonesense from a mathematical point of view. You write down formulae which ought to be quantum gravitational formulae and you get all kinds of infinities. It's pretty discomforting for a physicist to find infinities in the middle of his calculations.
-Edward Witten
I was thinking. . .
Why do we even bother discussing things that have no bearing in scientific fact in order to make scientific sense of the universe? Well, because we have to. Take, for example, the radiation of dark bodies. Boltzmann fixed the constant of proportionality by experiment, and found that the radiation was proportional to temperature raised to the fourth power. Okay fine and good. Then Planck founded quantum theory, and it was found that the constant, fixed by experiment, is really based solely on Planck's constant. Beautiful theories finding that nature agrees with them? So what is the real dichotomy in modern physics?
The problem is not exactly as Witten writes it. Yes, it is true that the calculations go strangly awry when quantum mechanics and relativity are combined. But look at the theories closely. Einstein begins with a philosophical principle - the principle of equivalence. He uses some pretty and pretty elegant mathematics, and shortly thereafter we have general relativity. Quantum mechanics starts with observed facts - that energy only comes in discrete packets. Loads of not so pretty math follows. But what relativity has as its strongest point - a philosophic basis - quantum mechanics lacks. There is no compelling reason why we should believe in quanta, other than observation. What physics needs is a PHYSICS (in the manner of Aristotle). It needs a compelling reason to think that this is the way the cosmos (in deference to Shulamite) should be.
aside - energy has mass according to general relativity. In quantum mechanics, the messenger particles that carry energy (photons) can't have mass because they travel at the speed of light. Now where are all of our ugly infinities coming from?
