First, remember that Kolmogorov complexity is only well-defined up to a constant, which is determined by your model of computation.
And that is why it makes little sense to talk about the complexity of one object without comparing or using it in relation to other objects, like the OP asked. If you implement the law of physics in Brainfuck code, on a x86 instruction set, or on a machine specifically dedicated to have the law of physics as a command, you can get wildly different complexities, even down to a few bit (think about the UTM that has a specific instruction that emulates the law of physics).
Does it even make sense to talk of relative Kolmogorov complexity when we're dealing with finite strings? For any two finite strings A and B, it is always possible to find some model of computation in which A is less complex than B (and vice versa, of course).
In the post Complexity and Intelligence, Eliezer says that the Kolmogorov Complexity (length of shortest equivalent computer program) of the laws of physics is about 500 bits:
Where did this 500 come from?
I googled around for estimates on the Kolmogorov Complexity of the laws of physics, but didn't find anything. Certainly nothing as concrete as 500.
I asked about it on the physics stack exchange, but haven't received any answers as of yet.
I considered estimating it myself, but doing that well involves significant time investment. I'd need to learn the standard model well enough to write a computer program that simulated it (however inefficiently or intractably, it's the program length that matters not it's time or memory performance).
Based on my experience programming, I'm sure it wouldn't take a million bits. Probably less than ten thousand. The demo scene does some pretty amazing things with 4096 bits. But 500 sounds like a teeny tiny amount to mention off hand for fitting the constants, the forces, the particles, and the mathematical framework for doing things like differential equations. The fundamental constants alone are going to consume ~20-30 bits each.
Does anyone have a reference, or even a more worked-through example of an estimate?