I’ve posted this before, but it’s worth seeing again in light of the Earth-sized planets Kepler just found.
A less-strong version of the Weak Anthropic Principle suggests that we’re here to see this universe because it has the properties to sustain us — this is not a tautology, though it sounds like one. It escapes that label only in that it implies the possibility of multiple universes. It means that if there are multiple universes with infinite ways to arrange the cosmological constants, we are here because this is one of them that fits the “goldilocks zones” for those properties, throwing the fine-tuning argument right out the window.
It’s not an argument that this universe was built around the necessity for our existence, though the two more popular versions of the postulate suggest as much. It is an admission that we don’t know how many rolls of the dice the potential multiverse (or infinite cycles of the universe) has had to get things exactly right to produce us. A corollary of this argument is that we also don’t know how many rolls of the dice this universe has had to create life — how many planets we’re finding that have the right makeup, size, and distance from their stars to have liquid water and organic chemicals all the other prerequisites for abiogenesis. If this universe is as replete with planets that failed to produce life as we suspect, perhaps we are unique in this universe — but it seems unlikely. It seems far more likely that life exists somewhere, given how many planets there are.
I don’t think Kepler shoots down most fine tuning arguments. In its modern form, the fine-tuning argument usually centers on the kinds of laws that prevail in the universe, and its initial conditions, which apparently have to be rather particular if we are to obtain universes with complex matter and chemistry and appropriate cosmology, lasting long enough for life to evolve. There seem to be ways to answer these arguments, but the existence of lots of other planets in THIS universe does not refute any part of that kind of fine-tuning argument.
great. now i have to go and reprogram The Matrix, and remove Kepler from the sys logs.
Dude, you’ve got root? Can you do something about these bug reports I keep filing about people’s brains already? Or escalate them to tier-two or something?
Lou: there are advocates of the fine-tuning argument who use it only in a planetary sense without getting into the cosmological fine-tunings. They’re pretty easily defeated when you point out that the vast majority of this universe would kill you instantly, and we co-evolved with our environment, but the fact that exoplanets exist that might fit the parameters necessary means God didn’t create this solar system or this planet “just right” to fit our puddle-like forms.
Yes, I just wanted to clarify that the more interesting (and probably more common) fine-tuning arguments are not addressed by Kepler