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Dissolving the Fermi Paradox

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Re: Dissolving the Fermi Paradox

#121

Post by rtkwe »

adrianN wrote: post #118
rtkwe wrote: post #59

Earlier quoted context omitted.

That also makes an assumption about the actual ability to make a machine capable of self replication. That in and of itself is a really hard problem as it has to replicate the entire high industrial base needed to create itself which is a LOT of stuff. Just our current technology requires hundreds of processes and chemicals to create critical things like the circuit boards and the components (capacitors, ICs, etc) on…

Earth is full of machines that are capable of self-reproduction (e.g. bacteria), and some of them are clever enough to build rockets, so I don't think it's such a big stretch to assume that von Neumann probes are possible.

That doesn't get us any closer, unless we stretch the idea of a Von Neumann probe to it's limits and include life seeding. Also we're a long ways away from anything near the scale required even surviving a trip to space much less actually living there.

Re: Dissolving the Fermi Paradox

#122

Post by krapp »

vertexFarm wrote: post #51
adrianN wrote: post #15

Earlier quoted context omitted.

Von Neumann probes could probably colonize a good chunk of the Milky Way given a few hundred thousand years.

I think that's an overly simplistic assumption, even if we assume they weren't designed by a rational actor who programmed a generation limit into them to keep them from totally converting all matter in the galaxy into probes (an absolute must, obviously). Life on Earth consists of Von Neumann machines. That's exactly what life is. Yet our life has not converted the entire mass of Earth into itself, and there's still…

It also assumes that all bodies in the galaxy are equally amenable to colonization and conversion into the necessary resources, and that for machines as complex as Von Neumann probes would need to be, there would be no such thing as mutation or evolution over innumerable generations which might halt the process of expansion.

And that most if not all probes in every generation will even find something other than empty space because the universe is very very very big and the likelihood of traveling in any direction and ever hitting anything is very very very small.

Although if you assume the universe is simple enough to describe on the back of a napkin then it probably is straightforward.

Re: Dissolving the Fermi Paradox

#123

Post by posterboy »

jobigoud wrote: post #82
gmuslera wrote: post #75

The reasoning seem to be "as we don't have enough data, lets conclude whatever I want". The Fermi paradox assumes that if there are aliens more advanced than us somewhere for a long time, they should be here by now. Maybe more advanced technology enables interstellar travel (maybe not, maybe is not practical at all), maybe they may not have all our motivations (expansion, technological advancement in our own focus, e…

When talking about the Fermi Paradox it's not about what this or that extra-terrestrial civilization might do. It's about what none of them is doing. When you say "maybe they don't want to expand", if you want this to explain the paradox, you actually mean "none of them want to expand". Because if just one did, we would see it.

We would see it? Do you have any idea how big the universe is, and how little we see? If there were astronauts on pluto right now, we could not detect them, I suppose -- I might be wrong, but the statement is bound to be true at some order of magnitude that's certainly smaller than the theoretically visible universe.

Re: Dissolving the Fermi Paradox

#124

Post by carapace »

taylorswift_ wrote: post #114
carapace wrote: post #111

Earlier quoted context omitted.

Look, my basic point is that we're not alone, rather nobody wants to talk to us because we're terrifying ravenous monsters. > but how do you know it exists if you've never been there? who told you? I can't tell you that in a public forum. And again, even if I could I wouldn't. Either you don't believe me in which case what's the point? Or, worse, you do believe me and want to go there. I'm not interested in helping a…

Oh I'd love to go to that lake... I agree it's foolish conjecture and I believe we are certainly not "alone". I had an experience when I was 10 that infused fear and curiosity in me. I'd like to say I am hopeful about our future but we are just evolved organisms from a long chain of creatures designed to compete for survival... it's in our own nature to self-destruct.

Ah well, time will tell, I imagine. :-)

If you want weird, edge-of-reality stuff that's fun and mostly safe I recommend the book "The Secret Life of Plants" ("Life" not "Lives", that's a different book): https://en.wikipedia.org/wiki/The_Secret_Life_of_Plants

Re: Dissolving the Fermi Paradox

#125

Post by chmike »

In my opinion, takling the ET existence using the drake equation is not efficient because it boils down to estimate or guessing values.

I favor the following reasonning. For simplification, let consider the universe as homogene. Now, let p be the probability that life emerges in one unit of time and space. (1-p) is the probability that life does not emerge in the unit of volume and space.

If v is the number of volume units in the universe and t the age of the universe in unit of time, then the probability that life never emerges in the universe is (1-p)^(v * t). If p is bigger than zero, this probability will tend to 0 with a growing v and t, regardless of the magnitude of p. This always converges to 0. Soon or later, life will emerge in the universe as long as it can emerge spontaneously.

What is the probaility that our solar system is the only place in the universe where life emerged. Let s be the volume of our solar system. That probability is (1-p)^((v-s) * t). Since s is very small relative to v, that probability is very close to the above probability. And with growing v and t this probability tend to zero. In other words the probability that life emerges elsewere in the universe after removing the volume of our solar system is not much affected. It still tends toward 1.

This should give you the idea. The only unknown variable is p. But even if we don't know it's value, we can draw two important conclusions from this. 1) it doesn't matter how small p is, soon or later life will emerge. 2) the probability that we are alone in the universe is tending toward 0 with increasing t and v.

Could we be the most advanced ? Why discarding the ufological data ? It's time this non-sense and ostrich attitude stops.

Re: Dissolving the Fermi Paradox

#127

Post by woodandsteel »

PaulHoule wrote: post #31

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 ca…

The problem with intelligent creatures that live in an ocean is they can't have fire, which seems to be essential for technological development.

Re: Dissolving the Fermi Paradox

#128

Post by stephenwinter2 »

btilly wrote: post #80

I have trouble calling it a paradox, because there is nothing that needs explaining in my view. Just throw in the fact that known fudge factors are important, and throw in the fact that there are more fudge factors that we don't know. For example the traditional Drake equation doesn't include as a major factor "large moon that stabilizes the axial tilt over evolutionary time". And yet that seems to be needed and at l…

I agree, I also can't see a paradox in terms of nature. And I would like to add an aspect of sociology (sociology is rarely discussed at this topic): Given mankind's industrialization period and decline of the ecosystem is normal it takes longer to get to an exoplanet than to ruin it. - So, what interstellar space travel really would be is this: The living mankind on Earth gives up itself and its home planet to spread the genes of those who plan its demise. http://www.hashsign.eu/html/blog/dominance/hadfield-hawking-... My answer to the Fermi Paradox is this: These bastards shouldn't get away with it.
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