Answers to the Fermi paradox

[Spoonwood]

How pray tell do you know that? You cannot just make assumptions based on what we've observed around some dozens of planets. You know why? Because those observations keep altering what is assumed. And also.. "observable universe"...what about what you cannot observe? No, you guys "know" nothing of the kind. And your guesses will keep changing as you observe more and more stuff, particularly since the knowledge of actual planets in other systems is so new to begin with.

One can say with certainty that the number of planets in the observable universe comes between 100 and 10^100^100^100^100^100^100^100^100^100^100^100^100^100^100^100^100. Consequently, we know ABOUT how many planets exist in the observable universe. The lower estimate definitely ends up less than the number of planets in the observable universe due to extrasolar planets found in THIS galaxy. The upper estimate comes as far, far too large (pretty sure it exceeds the number of atoms in the universe quite easily). Do you think that "vague" and "imprecise" such that we can't regard it as telling us ABOUT how many planets exist in the observable universe? Ah, but all of those come as natural numbers. And in the natural numbers one can find more than 10^100^... (as above) numbers greater than 10^100^...(as above). So, the estimate here eliminates far more possibilities of how many planets exist in the universe than it allows for. In other words, in ends up far more specific and precise in its domain of discourse than it does end up "vauge" and "imprecise". Therefore, we do KNOW ABOUT how many planets exist in the observable universe.

 

[ParadigmShifter]

Go easy on those numbers!

10^100 (a googol) is bigger than the number of atoms in the observable universe.

 

[uppi]

With just some calculations and estimations we can lower that upper bound much further: There are about 10⁸⁰ atoms in the universe and the sun has about 10⁵⁸ atoms in it. So if we assume the sun to be a typical star (give or take a few orders of magnitude), there can only be about 10²² stars in the universe. As every habitable planet needs an energy source and a sun won't be able to support 10 such planets, there cannot be more than about 10²³ planets than have any chance of supporting life.

Of course that tells us exactly nothing without an estimate how probable life is. A insanely huge number multiplied by an insanely small number can still be very small.

 

[Spoonwood]

With just some calculations and estimations we can lower that upper bound much further: There are about 10⁸⁰ atoms in the universe and the sun has about 10⁵⁸ atoms in it. So if we assume the sun to be a typical star (give or take a few orders of magnitude), there can only be about 10²² stars in the universe. As every habitable planet needs an energy source and a sun won't be able to support 10 such planets, there cannot be more than about 10²³ planets than have any chance of supporting life.

Of course that tells us exactly nothing without an estimate how probable life is. A insanely huge number multiplied by an insanely small number can still be very small.

How do you get the assumption that a sun won't be able to support 10 such planets? What about binary and trinary star systems? What if a planetary system has large planets which can support life and moons also which can support life? Sure, those moons may not qualify as planets, but that comes as irrelevant to the question of how many habitable structures can support life in the universe. Also, what happens to the amount of energy available to a planet when the system of nearby non-solar stars becomes much denser... e. g. a solar system with one star, a binary system one light year away in one direction, half a light year in another direction, 7/8 a light year away in another direction, 3/4 in another direction? Or can the systems of nearby stars not ever have an appreciable effect on how much energy a planet gets?

On top of this, as I expect you know but doesn't get expressed well in a public forum like this, an insanely huge number multipled by an insanely small number can come as very large, e. g. 10¹⁰⁰⁰ * 10^-55=10⁹⁵⁵ , as well as 10¹⁰⁰⁰*10^-10,000=10^-9000 as you said.