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Dissolving the Fermi Paradox

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Re: Dissolving the Fermi Paradox

#31

Post by PaulHoule »

Ecosystems are limited by the availability of water, not sunlight. Also there are more "habitable" places in the universe which are underground oceans (the default condition outside the frost line) as opposed to a tiny fraction of rock worlds which have to parametrically fine tuned to have water -- ex. there are 10-20 worlds that have underground oceans in our own solar system.

Why would a spacefaring civilization care about dry worlds inside the frost line? The most absurd thing about "Battle: Los Angeles" is not that aliens would come to Los Angeles (as opposed to Detroit) to steal water, but that they would come to a planet which has a thin layer on the surface as opposed to being just a run-of-the-mill dwarf planet or asteroid or comet or whatever you call it that is closer to 50% water.

If civilizations of the dark had deuterium fusion they might see very little reason to mess around with the puny resources to be found close to a star. It's entirely plausible that a generation "starship" could live off the land and hop from comet to comet to the next star in 10,000 years but probably the crew would lose interest long before the first millenium.

Re: Dissolving the Fermi Paradox

#32

Post by scott_s »

mirimir wrote: post #26
jerf wrote: post #22

Earlier quoted context omitted.

The article is not about picking parameters. The article is one meta layer up from that; they examine the distribution of parameters. I can't guarantee this is novel paper in general, but it's not something I've seen treated this formally before. I mean, it roughly conforms to what I've been saying for a while, but I only worked the math very intuitively and in a manner that could have been flawed, so I get no credit…

OK, picking distributions. I can't imagine that there's enough data to even do that.

I think you (and some others) are being dismissive of a good-faith attempt to formalize thinking of a problem with many unknowns. I can't access the paper itself, but commenter carry_bit posted a link to the slides, and the conclusion slide says:

The Fermi question is not a paradox: it just looks like one if one is overconfident in how well we know the Drake equation parameters.

• Doing a distribution model shows that even existing literature allows for a substantial probability of very little life, and a more cautious prior gives a significant probability for rare life.

• The Fermi observation makes the most uncertain priors move strongly, reinforcing the rare life guess and an early great filter.

• Getting even a little bit more information can update our belief state a lot!

I think their arguments deserve more consideration than what they are getting in this thread.

Re: Dissolving the Fermi Paradox

#33

Post by amelius »

ssijak wrote: post #6
jpm_sd wrote: post #2

TL;DR - It's not a paradox, because we're probably alone. Kind of a letdown!

How did you/they calculate that probability of being alone? Anybody who tries to slap some number on such things as the probability for life to emerge is dishonest at least.

Imagine a two-dimensional grid of squares, where all the squares are randomly chosen to be either black or white. Imagine that somewhere in this grid there's the appearance of a smiley in a 12x12 rectangle. How would this smiley compute if it's alone in the grid, and how close the nearest other smiley can be expected to be?

Re: Dissolving the Fermi Paradox

#34

Post by titzer »

light_hue_1 wrote: post #8

It's "papers" like this by people that are either clueless or malicious that make everyone pine for the pre-arxiv days. Everyone considered this option. From the very first day the paradox was posed. We don't know the parameters well, it's within our margin of error that no one else is out there, so it's an option. This is such an absurd claim to take as your own that it's literally on the wikipedia page! It's also e…

I dunno, I kind of doubt that Eric Drexler is clueless or malicious. Maybe if you read the paper and understood their approach you'd have less of a knee-jerk reaction. They are arguing (as pointed out in comments elsewhere) that the math on probabilities should be using distributions, and this is what they do, and they go on to show that the resulting probabilities are far, far lower than the simplistic Drake equation would suggest.

Re: Dissolving the Fermi Paradox

#36

Post by jerf »

mirimir wrote: post #26
jerf wrote: post #22

Earlier quoted context omitted.

The article is not about picking parameters. The article is one meta layer up from that; they examine the distribution of parameters. I can't guarantee this is novel paper in general, but it's not something I've seen treated this formally before. I mean, it roughly conforms to what I've been saying for a while, but I only worked the math very intuitively and in a manner that could have been flawed, so I get no credit…

OK, picking distributions. I can't imagine that there's enough data to even do that.

"OK, picking distributions. I can't imagine that there's enough data to even do that."

Of course there is enough data to pick the distributions of estimates given by various people. We have all the estimates given by people in hand.

You seem to be being dismissive without even remotely engaging with what is being discussed here.

Let's skip over the part where you fall back to the claim that the distribution of probabilities given by people isn't relevant to anything, because that's not important to the paper. The entire point is to examine the distribution of such probabilities, and compare it to the observed universe, and that's it. Nothing more.

Re: Dissolving the Fermi Paradox

#37

Post by ISL »

mdpopescu wrote: post #28
ISL wrote: post #5

If the argument stated above is correct, there is an awful waste of space. (Thanks, Carl!) There is nothing in physical law to suggest that here is substantially different from anywhere else in the universe. To believe that here is manifestly different from every other place in the universe is a really surprising claim.

First, we know with absolute certainty that here is substantially different from anywhere else: we know there's life here, we haven't found life anywhere else. (And the null hypothesis is that we haven't found it because it doesn't exist.) Second, it's a waste of space only if 1) it was created on purpose and 2) the purpose wasn't "to allow us space to expand". If either of those is false, I don't see how it can be c…

First, we know with absolute certainty that here is substantially different from anywhere else: we know there's life here, we haven't found life anywhere else.

I'll take the other side of that bet. What odds are on offer (10^15:1? 10^80:1?)?

Re: Dissolving the Fermi Paradox

#38

Post by jerf »

scott_s wrote: post #32
mirimir wrote: post #26

Earlier quoted context omitted.

OK, picking distributions. I can't imagine that there's enough data to even do that.

I think you (and some others) are being dismissive of a good-faith attempt to formalize thinking of a problem with many unknowns. I can't access the paper itself, but commenter carry_bit posted a link to the slides, and the conclusion slide says: The Fermi question is not a paradox: it just looks like one if one is overconfident in how well we know the Drake equation parameters. • Doing a distribution model shows tha…

You should be able to access the paper. Arxiv doesn't require any logins or credentials or anything; just check the "download" section in the upper right. This should go straight to the PDF: https://arxiv.org/pdf/1806.02404 (Unless, you just mean you're on a device that can't render PDFs or something. It's a simple PDF, though, even a phone should be able to handle it.)

Re: Dissolving the Fermi Paradox

#39

Post by goatlover »

psychometry wrote: post #35

Does anyone else find this question totally uninteresting? There's no discussion to be had about this paradox that doesn't devolve into an N=1 predictive model.

I find it interesting because if N=1, then we're an incredibly statistical fluke, and yet there's no reason to suppose that our solar system or planet is that much of an anomaly.

Re: Dissolving the Fermi Paradox

#40

Post by goatlover »

mdpopescu wrote: post #28
ISL wrote: post #5

If the argument stated above is correct, there is an awful waste of space. (Thanks, Carl!) There is nothing in physical law to suggest that here is substantially different from anywhere else in the universe. To believe that here is manifestly different from every other place in the universe is a really surprising claim.

First, we know with absolute certainty that here is substantially different from anywhere else: we know there's life here, we haven't found life anywhere else. (And the null hypothesis is that we haven't found it because it doesn't exist.) Second, it's a waste of space only if 1) it was created on purpose and 2) the purpose wasn't "to allow us space to expand". If either of those is false, I don't see how it can be c…

> First, we know with absolute certainty that here is substantially different from anywhere else: we know there's life here, we haven't found life anywhere else.

We haven't even ruled out life existing on Mars or under the ice of Europa, let alone X light years away.

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