Sentient life in the universe

Incorrect. The chances of us being alone in the Universe are unknown. We simply don;t have sufficient data to calculate probability for something like intelligent life in teh Universe. We know of exactly one instance, and one instance only, of it ever happening anywhere. That's enough to serve as a proof-of-concept (regardless of how life arises, whether through divine Creation, abiogenesis, or anything else, if it can happen here, it can happen elsewhere given the same conditions), but is not sufficient to tell us how frequently it can happen.You are correct that there are trillions of stars, and that planetary systems seem to be relatively common, as do the chemical building blocks for life (we see organic chemicals and water naturally all over the place). However, we have not yet firmly established the conditions that give rise to life (whether that be conditions favorable to abiogenesis or simply the whim of a deity), and so cannot possibly determine how common those conditions are.That said, since it has happened here, and the number of stars potentially hosting Earth-like planets is staggeringly large, I'd tentatively place myself in the "we're probably not alone" camp.

I didn't say survive. Once life exists, it does seem to be extremely adaptable to a wide range of environments.I was talking about the conditions necessary for life to form, in the first place. We have multiple ideas at this pioint as to what those conditions might be. Theists tend to believe that teh only required "conditions" are the whim of a deity. Those who subscribe to abiogenesis have a variety of hypotheses regarding the necessary conditions.But the point I was making is that we don;t know currently the type of environment needed for life to form, and so then we do not know how common those conditions are in the universe, and thus we do not know how probable other life in the Universe is.One in a hundred solar systems could contain a planet capable of producing life (producing, not sustaining). Or it wcould be one in a thousand, or one in a million, or one in a trillion - we just don't have enough data to be able to say. Your comments regarding the probability of alien life require a level of knowledge that we do not have. You are speculating based on inadequate information and pretending your assertions carry weight.They do not. No, they aren't. They remain "unknown." We need still more data. We need a working theory for how life originates (be it abiogenesis or anything else) before we can make such statements. There is enough knowledge available to suggest only that there are lots and lots of stars, and apparently lots and lots of planets, and that organic compounds and water exist commonly throughout the Universe.That supports the notion that Earth-like life may exist elsewhere, but it does not in any way give us sufficient grounds to calculate the probability of the existence of extraterrestrial life.Alien life, from what we know, is extremely plausible. We have insufficient data to determine how probable. Do you see the difference? Perhaps. perhaps not. Bacteria really aren't all that simple, you know.More poignantly, what makes you think that extraterrestrial life will have any sort of Earth analogue? Given formation and evolution in an environment that isn;t simply exotic on Earth but is in fact literally otherworldly, what makes you think whatever life we find will be able to be classified as bacterial, or even anything similar?What makes you think we would even recognize alien life when we first see it? Our world is indeed noisy, but not all transmissions are strong enough to be picked up at interstellar distances, and they fade with distance (blocked by impediments, simple dispersion of the signal until it's too weak to be picked up, etc).But think of this: our galaxy is somewhere around 100,000 light-years across. We are most of the way out on one arm.We've been broadcasting radio signals that could be detected by aliens for some 60 or so years. That means we're detectable to species that have a presence roughly 60 light-years away or less. That's 0.06% of the diameter of just our galaxy."Too far away" to be detected on a galactic scale (let alone an intergalactic one) doesn't have to be very far at all.