Dissolving the Fermi Paradox

<i>&quot;When we update this prior in light of the Fermi observation, we find a substantial probability that we are alone in our galaxy, and perhaps even in our observable universe (53%–99.6% and 39%–85% respectively). ’Where are they?’ — probably extremely far away, and quite possibly beyond the cosmological horizon and forever unreachable.&quot;</i><p>Opinions like these (I stop one step short of calling them findings, as this is speculation either way) resonate with me. I&#x27;m, too, more convinced by the Rare Earth hypothesis, and I find it quite plausible that we&#x27;re indeed the sole sentient lifeform in the Universe - at least throughout the time of our existence.<p>This belief never gained me much popularity though. And this is what I&#x27;m fascinated about - how badly a lot of people take to this view. Even seemingly rational individuals seem to have some deeply ingrained, emotional need to defend the belief in ETI.<p>My personal theory is that this emotional mechanism is actually of religious nature; just in disguise. It&#x27;s very telling that the most popular narratives involving ETI are usually quasi-religious.<p>The aliens would typically &quot;teach us how to live in peace&quot; (if we&#x27;re willing to sit down and listen, of course), or turn away from us in disgust (for our sins), or scold us for our poor moral judgment and deeds; generally trap us in shame. Or they&#x27;d be quite diabolical and bring all sorts of plagues upon us, giving us a taste of our own medicine for we&#x27;re wicked.<p>But the eschatological component is rarely absent either way.<p>Even this sceptical paper uses biased language through and through, consistently referring to the belief in the prevalence of ETI as &quot;optimistic&quot;, and calling the opposite belief &quot;pessimistic&quot;. But why?

The streetlight effect, we are searching in our close neighborhood, for signals that we would use in our current kind and stage of civilization, and because we didn&#x27;t find anything we conclude that in the whole universe there is no life or intelligent life at all.<p>Maybe SETI search should add several terms to the drake equation to understand odds of hitting gold. Is not enough to be intelligent life, to be found in the way we are searching for it, distance, way of communication, culture, kind and stage of civilization, wish to be found, wish to expand, biology, and probably more are just terms in the equation that lowers the probability for us to find anything. There are too much implicit assumptions about what we are searching for, and maybe there is none that fits that because some basic rule that we don&#x27;t know yet, as we are not advanced enough (a dark forest is just an example).<p>Is like assuming that advanced enough cavemen will be communicating across the galaxy with louder drums. And that as we hear no drums in space, there is no life anywhere.

The paper basically says that the Drake equation is just a guess, and if we’re going to guess, we might as well do so using probabilistic models. Their model puts the Great Filter behind us.<p>This makes intuitive sense too — an early Great Filter simply has to stop life from occurring, while a late Great Filter has to deal with the complexity of preventing life from doing what it does best (surviving and spreading in a “Life finds a way” style). Concretely, an early Great Filter has fewer variables it must affect than a late Great Filter. Like the paper says, we are probably alone, but there’s little reason to be alarmed about it.<p>And if you happen to believe that AGI and a Singularity are the inevitable outcome of intelligent life, the case is even stronger that we are the first, last, and only. However powerful the Great Filter might be, it’s unlikely that a super-intelligence would succumb to it.

The Drake Equation’s always been an exercise in multiplying a bunch of wild-ass guesses together and ignoring the error bars. At least this article pushes it out to ignoring the error bars <i>on the error bars</i>.

I have a personal theory about the great filter:<p>The great filter is evolution converging to a local maxima and not evolving creatures capable of higher intelligence.<p>We&#x27;re scared about the mass extinctions on Planet Earth while at the same time they were the ones that cleared the field for different animals to evolve. Case in point, the Dinosaurs going bust paved the way for small mammals (then large mammals, etc)<p>&quot;But couldn&#x27;t we have intelligent dinosaurs&quot; maybe not? (Because of a bunch of stuff that only came later like animal packs, family life, etc - though it might be argued that some dinosaurs had that)<p>Then we have the fact that mammals are born much more frail than other species and needs &quot;a family&quot; to take care of them for a while (and human&#x27;s big heads made that &quot;while&quot; into &quot;a lot of time&quot;)<p>But without that you don&#x27;t get societies organizing. And the bigger the society the more you can do with it.

The Fermi Paradox always seemed like an incredibly simple-minded idea to me. So much so, that I don&#x27;t quite understand how someone as intelligent as Fermi could seriously put it forward.<p>The idea that <i>life</i> in the universe will be comprised of humanoid-esque beings that have the same perception of time as us, or the ability to communicate in a &quot;language&quot;, is just a human-centric idea. It&#x27;s us, projecting our own worldview (which has developed through millions of years of evolution) on to the infinite universe. This is the fundamental problem with positivism; using your current limited sensory knowledge to construct a complete world-picture.<p>Even <i>life</i> itself is not a neutral word; it mostly just means &quot;carbon-based entities like those on Earth.&quot; Perhaps the reason the universe seems so empty is because we only have the ability to see things like ourselves?

&gt; we find a substantial {\em ex ante} probability of there being no other intelligent life in our observable universe<p>This is very sobering to read if true. It’s all on us. Life is even more precious than we thought and every human life extinguished even more of a loss to the universe. If we could only band together and see this.

TL;DR: &quot;We don&#x27;t know how often abiogenesis happens, and our uncertainty for its rate is extremely large. The error bars extend so far into &#x27;effectively zero&#x27; that we could or could not be alone, it&#x27;s a toss-up&quot;. Seriously, this paper hinges entirely on the prior distribution for the abiogenesis rate.<p>Longer comment:<p>The paper considers each parameter of the Drake as a probability distribution over some range. Notably, they assume that f_l in the Drake equation (the fraction of habitable planets that actually develop life) may vary over (at least) <i>200</i> orders of magnitude. Yes, you read that correctly.<p>Naturally, they thereby get a long tail of &quot;planets essentially never develop life, even despite there being so many of them&quot;.<p>My main critique (as someone with no further credentials) is that the prior probability distributions they assume for the parameter distributions are more or less meaningless. Their results say &quot;<i>if</i> we assume that the log of f_i (life-bearing planets that develop intelligent life) is uniformly distributed between log(0.001) and log(1), similar for other parameters, <i>then</i> the probability of being alone in the milky way is &gt; 50%&quot;.<p>Specifically, by far the largest impact here is from assuming some distribution for f_l that covers 10x as many orders of magnitude (!) as the remaining parameters <i>together</i>. I&#x27;m very certain (but haven&#x27;t done the math) that slightly tweaking the sigma they assume for the corresponding log-normal distribution (that sigma is <i>50 orders of magnitude</i>) would drastically impact the results. They do a lot of dancing around that fact (discussing how little impact the priors of other parameters, or even the center of the log-normal distribution for f_l have), but fundamentally the result boils down to:<p>&quot;We&#x27;re extremely unsure how often abiogenesis happens, and this parameter dominates everything else.&quot; Followed by some math that (oversimplified) boils down to &quot;if we set the rate of abiogenesis to effectively zero half the time, then half the time we are alone in the universe.&quot;<p>PS: Title should probably have (2018).

The claim that we are alone in the observable universe seems incredibly arrogant. We don&#x27;t have enough data for such an extraordinary claim.<p>Time and time again we have discovered that we are less special than we thought. Life appeared quickly after Earth was formed. I&#x27;m convinced the universe is teeming with life.

Seems to be breakthrough work. I never went really far into the Fermi paradox and was scared a &quot;great filter&quot; was in front of us. This article seems to imply it is behind us. That makes the need to have a backup planet and expand into the universe even more vital to keep the tiny flame of life and consciousness alive. Why shouldn&#x27;t we put more ressources into it ? My reference source about it is <a href="https:&#x2F;&#x2F;waitbutwhy.com&#x2F;2014&#x2F;05&#x2F;fermi-paradox.html" rel="nofollow">https:&#x2F;&#x2F;waitbutwhy.com&#x2F;2014&#x2F;05&#x2F;fermi-paradox.html</a>

If we just stop for a moment and think how little we can “receive” from our surrounding (100 hundred light year max?) and how vast the universe, even our galaxy is and how incredible long the time span between the birth of the first stars and the birth of our petite civilization then we will realize we still can deduce nothing about the existence or non-existence of other civilizations.

We were all taught that humans are not special and the earth is common. Well, it looks like everybody was wrong. We are unique after all.

(2018)

When government literally admits that we have daily sightings of UAPs they cannot explain - i do not understand why we still also say there is no evidence of alien life?<p><a href="https:&#x2F;&#x2F;www.reddit.com&#x2F;r&#x2F;UFOs&#x2F;comments&#x2F;nf7h0x&#x2F;wow&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.reddit.com&#x2F;r&#x2F;UFOs&#x2F;comments&#x2F;nf7h0x&#x2F;wow&#x2F;</a>