A fascinating article over at MSNBC reports on how data gleaned from observing quasars has led some scientists to conclude that some physical “constants” like the speed of light or the electron’s charge may not be constant after all. As one of the scientists interviewed in the article notes, this presents a sort of Quinean problem: To measure one thing, you need the other thing you’re using to measure it to be stable. (In their metaphor, if you want to know whether something’s growing, it helps to be sure your ruler isn’t shrinking: Strictly speaking, the best you can do is talk about the ratio of the ruler to the object.) I don’t know enough physics to know how serious a wrench this throws into the machinery, but it sounds like it would potentially upset a lot of our inferences about the universe. For instance, if we’re calculating the age of the universe by working backward to a singularity from the observed rate of expansion now, that’s going to depend on the assumption that our local and recent measurements of things reflect some underlying, unchanging “laws of nature.” But if they’re really just “guidelines of nature”—if the inductive leap is no more justified than my walking around the neighborhood and concluding that all humans speak either English or Spanish—where’s our Archimedean point from which to make these sorts of extrapolations? (Are there at least meta laws specifying how the constants vary over time and space?)

A sidebar also alludes to the apparent “fine tuning” of the physical constants of the universe to allow for the emergence of life. Some theists have regard this as evidence for the existence of God, since life is possible only given that very many of these constants are pretty close to their observed values now. Since, they argue, it’s phenomenally improbable that all the numbers would line up just right, the physical laws must have been set up by some intelligence to allow for us to be around to mull the problem over.

That was always a sort of weird argument. If you tell me that there’s a bag with ten black m)arbles and five white ones, I know how to figure the probability of drawing a particular color. If you tell me the speed of light is 299,792,458 meters per second and ask me how probable that is (as opposed to, say, 299,700,210 meters per second), I just have no idea how to even begin thinking about it, let alone how to compare it to the probability of an omnipotent consciousness just being there at the beginning of everything. How improbable was it for there to be “something rather than nothing”? It’s not even obvious that the question, however gramatically well-formed, is intelligible: We calculate probabilities in the context of certain constants.

Still, if those numbers vary, it seems like we might have an answer to the intuitive problem that doesn’t resort to multiple universes. Because then it might just be that the constants have been “fine tuned” for life recently, in this particular corner of a very big and old universe.