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prase comments on Query the LessWrong Hivemind - Less Wrong Discussion
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We have observed that the universe is regular and that there is nothing special about Earth, as far as we know. That's quite a good basis for the assumptions, in my opinion. Although I am not completely sure what you mean by "physical" here.
I don't understand why, in the title of the linked article, possible information leak from black holes is referred to as "gravity not being constant". Nor I understand what this has to do with induction or falsificationism.
The Copernican Principle has served us well. Ironically, it turns out it was somewhat misguided about the Earth itself. I don't believe that out of the single-digit percentage of planets yet discovered that are categorized as "Earth-like", that any of them fall particularly close on the parameters relevant to "humans would be comfortable living here if they brought the right flora and fauna with them Spore-style"). Certainly none of them have been around yellow stars and all have had rather bizarre irradiation profiles.
As to the regularity of the universe -- well, that's what the notion of a variable constant of gravity was about. I've seen conjecture that 'dark matter'/'dark energy' might be nothing more than our failure to recognize that the gravitational constant changes in some regions of space. The thing about the information leak from black holes has to to with a conjectured way of testing that (even Hawking Radiation doesn't retrieve information from black holes; that according to what we now know is a one-way trip.)
Well, imagine spacetime has a definite, discrete barrier. On our side there's still 'physical' stuff. On the outside of that barrier... there's nothing. No physical anything. Not even space. (This gets headachey when we start realizing that means there's no "outside" outside there...)
Suffice it to say that I was being 'colorful' in saying that we have no way of knowing that the universe doesn't just stop at the edge of the Earth's lightcone. (It's actually a pretty mundane assertion; most discussions on the matter I've ever heard of make this the null hypothesis.)
You have a better epistemology for evaluating beliefs about the observable universe?
By special, when speaking about fundamental physics, I certainly don't mean "is capable of maintaining carbon-based life". Earth may be unique in this respect while the physical laws being the same everywhere.
Even if this were true, so what? Instead of standard Einstein equations one would get a modified set of equations with a new dynamical field instead of constant G. This wouldn't challenge regularity of the universe.
The null hypothesis is what? That the universe stops just there, or that we have no way of knowing?
It seems strange. If you walk along an unknown road and are forced to return at one point, do you (without additional information) suppose that the road ends just beyond the last corner you have seen?
By the way, the relevant Earth's lightcone is precisely your lightcone or mine?
In practice the former.