Comment on Sea Level

• exasperation@lemmy.dbzer0.com ⁨1⁩ ⁨week⁩ ago

  So a planet isn’t just 50% likely to form with rocky bias withín the frost line, it is certain to do so.

  No, you’re skipping a step. For any n number of chances, the likelihood of something with probability p happening at least once is 1 - (1 - p)^n . You may think that with high enough n that it doesn’t matter what p is, because the exponential increase from n overwhelms the math to where the whole term basically converges onto 1, but my point is that there are combinatorics where the exponential increase in n is still dwarfed by the effect of the factorial increase in 1/p.

  The probability of a rocky planet to form within a habitable zone is about 20% for any given star, according to your earlier link. How many will have a moon like ours? How many other life-sustaining characteristics will it have? If your argument is that the probability is 100% for every star, well, that’s just wrong. If your argument is that it is inevitable in that the probability approaches 100% if you look at enough stars, then you’re ignoring the entire point I’ve been making here, that you would have to show that the probability p is large enough that one would expect the overall probability to be found in at least some of the n stars viewed.

  The fact that something has happened nearly every time we see a chance of it happening very much does make it a high probability event, cf. Bayesian inference.

  No, my deck of cards counterexample directly disproves this conjecture of yours. And you can’t talk about Bayes theorem while simultaneously saying that this isn’t a discussion about probability.

  And you also can’t talk about natural laws without probability, either, as quantum mechanics itself is probability distributions.

  So I’ll continue to point out that the vastness of space might mean that the n is in the order of 10^21, but I can simultaneously recognize that 10^21 is a mind bogglingly large number while still not being large enough.

  source

  • crapwittyname@feddit.uk ⁨1⁩ ⁨week⁩ ago

    And you can’t talk about Bayes theorem while simultaneously saying that this isn’t a discussion about probability.

    I can, precisely because you are forcing this discussion to be about probability

    And you also can’t talk about natural laws without probability, either, as quantum mechanics itself is probability distributions.

    Literally none of the effects you have chosen to discuss are quantum effects.

    Look I’m sorry, but I don’t think the evidence points to p<10E-21 or anywhere near it. Why would the only solar system we’re able to study be so unique? It’s magical thinking. Apart from the moon and plate tectonics being nice, but not essential to complex life, which other factors are you proposing conspire to lower the probability of life to this practical impossibility?

    source

    • exasperation@lemmy.dbzer0.com ⁨1⁩ ⁨week⁩ ago

      I’m pointing out the fallacious reasoning behind your view that with enough chances, it is inevitable that every possible outcome occurs at least once. That does not necessarily follow, simply because it is possible to generate events of infinitesimal probability, simply because n! grows much faster than x^n. That’s just plain math.

      Turning to whether the rare earth hypothesis itself is correct or not, I don’t actually have a strong view on this. I just know that you can’t reason your way into disproving the rare earth hypothesis simply by saying “the earth is possible and therefore common, because everything that is possible is inevitably common.”

      I don’t see how else this could be anything but probabilistic. Unless you’re saying every star is the same size as the sun and every star has an earth-like planet orbiting it in he habitable zone, the probability of those things is obviously less than 100%. We can already observe counterexamples that proves those aren’t 100%.

      So if you want to argue that there’s no way the probability is less than 1 in 10^21, fine. Then we’re having the conversation about the actual probabilities. But my whole point, since my first comment in this thread, is that it is not enough to say “I think there are 10^21 planets so life is inevitable.” That’s not sufficient to support that conclusion.

      Debate whether a large moon, plate tectonics, a magnetic field, an atmosphere, an ozone layer, a Jupiter-like neighbor, a G-type star, and what ratios of specific elements need to be present on a planet to qualify. I’ll leave the actual estimates of those probabilities to others. But each of these factors has a non-100% chance of happening on any given planet, and it becomes a question of whether the probabilities stack in a way that overcomes the sheer number of stars and planets there are. And that’s the thing I’m sure about, that you simply can’t ignore the factorial expansion of those factors because you think that there are enough planets in the universe to make that irrelevant.

      source

      • crapwittyname@feddit.uk ⁨1⁩ ⁨week⁩ ago

        your view that with enough chances, it is inevitable that every possible outcome occurs at least once.

        Can you point to what I have written that has led you to this misunderstanding? I’m not an idiot and I certainly do not believe this nonsense. Thanks.

        source