“It’s worse than that. We haven’t even found another stellar system that resembles our own, which has effectively thrown their “nebular hypothesis” for planetary evolution into the trash bin.”
Actually, there are computer models which do show solar systems relatively like ours forming. The problem is that gas giants tend to shred such systems to bits. Something ... and this is more plausible than the use of vague language may suggest ... stopped Jupiter from descending into a very short orbit and pulled it back to a wider orbit. This knocks a few zeroes off any estimate acquired using Drake’s equation, but in no way disproves the nebular hypothesis.
>> Correct, although most scientists refuse to acknowledge this and cling to the “cosmological principle”, an assumption that contradicts the evidence. <<
Well, the Hercules-Corona Borealis Great Wall apparently contradicts the cosmological principle, but that’s actually irrelevant. It’s a quirk of relativity that no matter where you are, you are at the center of the universe. Not that you seem to be relatively in the middlish region of the universe, but the exact center to as precise a degree as can ever be measured. So it’s not coincidental that we’re at the oldest part of the universe, but it’s not meaningless, either. Further portions of the universe are shown to have galaxies composed mostly of star systems with very low levels of heavy elements, demonstrating that they are younger, and therefore lack the prerequisites of life.
>> The only thing I’m wondering is, does temporal distortion kick in if the motion is due to the expansion of space itself? <<
Wow... I have to retrace all my thinking on this. (Which is based purely on following the logic of the physics; I don’t have near the math skills to know any real, math-based physics.) The quick, sloppy answer, which I’m not sure is right, is that to catch up the matter, you’d have to go travel faster than light, which would mean you’d go backwards in time. If you simply always were at a distant part of the universe, you’d be going closer to the speed of light, relative to earth, and so you’d be age slower, and so again, the universe would be younger. But if you warped time-space, I guess you’d be on a time-space island of old universe surrounded by younger universe? But any light (or any form of entropy) reaching you would be the same light reaching the younger universe, so you’d still appear to be at the center of the universe, with nothing but your advanced age to suggest otherwise?
>> Seems like an optimistic estimate to me even so. If we didn’t know there was life on at least one planet, I would say the probability was effectively zero. Since there is life on at least one planet, then either it’s due to some extraordinary circumstance (like divine intervention), or we hit the biggest lottery drawing ever held. <<
Well, the anthropological principle would say that if there’s going to be life on any planet in the universe, and you’re life, you’re going to be on that planet. I think applying the anthropological principle to the multiverse is a copout, until the dimensions past four are somehow proven to be substantially thick... but it’s not like you’re going to pop into sentience on the wrong planet and then say, “Oh no! Wrong planet!” and die.
“Actually, there are computer models which do show solar systems relatively like ours forming.”
A computer model can be made to show you anything you want to see though. In the real world observations of systems with exoplanets, we haven’t found any resembling our configuration yet.
We’ll never be able to actually witness a system forming over a long enough timescale to confirm or deny the nebular hypothesis, so you cannot test the models that way. However, we have predictions from the models BEFORE exoplanets were observed, and that precludes scientists from having done any funny business to force their algorithms to fit observations when they produced those predictions. The predictions were a failure, and that should doom the hypothesis, as far as I’m concerned. I wouldn’t trust any new predictions to not simply be the result of tweaking the algorithm to produce the results they want.
“The quick, sloppy answer, which I’m not sure is right, is that to catch up the matter, you’d have to go travel faster than light, which would mean you’d go backwards in time.”
This can’t be right, because anything with mass can’t even reach the speed of light, much less go faster. I’m thinking that temporal distortion must happen regardless of whether you are moving or the space expanding is moving you though, because according to relavity, the cause of the motion wouldn’t matter, only the rate of motion from whichever frame of reference you pick.
“I think applying the anthropological principle to the multiverse is a copout, until the dimensions past four are somehow proven to be substantially thick... but it’s not like you’re going to pop into sentience on the wrong planet and then say, “Oh no! Wrong planet!” and die.”
I think the whole multiverse stuff is silly... it isn’t wholly illogical, but it’s also not really science, since the nature of the proposition makes it impossible we could ever prove or disprove it by scientific means. So it’s more philosophy dressed up like science than science.