Yes, but I still can’t speak to the probability of that sequence occurring without knowing the range that each is drawn from.
Known number * Unknown number = Unknown number
Or to put it another way - let’s say that I make this offer:
You give me $500. I will give you, in return, some amount of unknown value back. Is it a good deal?
What if you only have to give me $100? Does that change your analysis?
If so, send me a PM - I have a deal to offer you…
Thanks, Phil. With the first equation, I misunderstood what you were trying to do. I thought you were taking the probability of life at one star and multiplying it by all stars for some reason. Now I see you were doing statistics. Of course, you’d have to factor out all the stars that don’t have planets and/or can’t support life. I’m not sure how we would determine the latter, unless we mean only life like ours. We’d also need to determine that first probability. What were the chances of us being here? 100%, apparently. I’m not sure how we would calculate the hypothetical, though.
Well, it gets tricky here.
What was the probability that you were born and became you?
On the one hand, you might say that probability was 100%. It happened after all, right?
On the other hand, you could say that, even if we’re only looking forward from say, 100 years ago, the probabilities were miniscule. Assuming your grandparents were already born by then, your grandfather had to meet and fall in love with (or at least have sex with) your grandmother. On each side. Out of all the sperm-egg possibilities, the right match had to occur. If a butterfly had been flapping it’s wings at the wrong time, your grandmother might have been distracted, delaying things by 10 minutes and changing all the variables, and so on.
So even with something that we sort of understand, we can plausibly defend probability estimates from 100% down to nearly 0%.
Same way people can say there ain’t no god – cause they don’t see it.
That’s my point. It’s somewhere between 0 and 100, and I don’t see any way to determine where it will fall.
We admittedly don’t have a good feel for what the probability of life is; the weak anthropic principle prevents us from even saying it’s at least high enough to expect at least one planet (for all we know there are a zillion ‘parallel’ universes where life never arose for every one that did). But it’s not immediately dismissable as obviously impossible either, if the expected range is high enough to allow for plentiful life.
That’s largely why there’s so much interest in determining whether there was life on Mars or not. Even if we find the most crude, primitive, barely-qualifies-as-living of organisms, it ups the probability considerably if we’re finding other life in our own backyard.
(Though then that starts dragging in things like panspermia theories…)
The same way a religious person can look at the ridiculously immense size of the universe and somehow come to the conclusion that this planet and everything on it is somehow special.
It’s lovely to live on a raft. We had the sky up there, all speckled with stars, and we used to lay on our backs and look up at them, and discuss about whether they was made or only just happened. Jim he allowed they was made, but I allowed they happened; I judged it would have took too long to make so many. Jim said the moon could ‘a’ laid them; well, that looked kind of reasonable, so I didn’t say nothing against it, because I’ve seen a frog lay most as many, so of course it could be done.
There might be a big evil empire out there that destroys civilizations that become interstellar travelers.
The Ur’Quan aren’t so tough.
I find the whole Seti project largely misguided, because not only does it assume aliens who use the same technology as us, it’s looking for a technology that we only used for a tiny period in our entire history. If there are aliens out there, the chances that they are in the brief period of using radio waves during the exact time we’re looking at their area of space is practically zero.
If lightspeed really is an absolute speed limit, that easily explains the lack of encounters. Stars are really far apart.
I don’t know, but if it were only just us, it seems like an awful waste of space.
In all seriousness, I don’t think we’re alone. I’m confident that there’s intelligent life out there. I’m also reasonably confident that we don’t rate even close to intelligent on whatever scale that intelligent life uses to measure intelligence.
At best, it might explain the lack of physical encounters. It doesn’t address the lack of radio signals and whatnot.
And, if light speed is an absolute barrier, stars are far apart in terms of the amount of a human’s typical lifespan. But if aliens lived much longer than humans, this is not such a significant issue. If your lifespan was 10,000 of our years, then spending 10-100 of those years on a ship traveling through space at 0.5X light speed would not be such a big deal - comparable to an ocean journey for us a century or two ago.
cf. Stanis Law Lem’s Fiasco
And if a frog had wings, it wouldn’t bump it’s ass on the ground. :)
If lightspeed really is an absolute speed limit, that easily explains the lack of encounters. Stars are really far apart.
Sure, but that’s where worm holes come in.
Why does that need to be addressed? The first radio broadcast was made barely over a hundred years ago, and we’re already moving on to lasers and fibre optics. Not to mention that looking for radio waves assumes aliens used them ever, which is hardly a given.