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This will sound stupid... but as we find out that the universe is bigger and bigger and there are more clusters, galaxies, stars, and planets then we have imagi
by haunter 3y ago
This will sound stupid... but as we find out that the universe is bigger and bigger and there are more clusters, galaxies, stars, and planets then we have imagined before (Laniakea have 100,000–150,000 galaxies and the Milky Way _alone_ have 100–400 billion stars)
so does that increase or lower the chance that there is _any_ kind of life outside there? Maybe not carbon-based life but any kind. Next question would be I guess that what is "life"
Fascinating stuff nonetheless
- pfdietz 3y agoRealize that if the cosmological constant has the nonzero value that appears to be the case (in the lambda-CDM model), then only about 6% of the galaxies we see are still reachable. The rest will be carried away by accelerating expansion so quickly that a photon emitted from us right now (or any slower than light spaceship) will never reach them. Of course more stars increases the chance of life out there, but without a good handle on the chance of life arising around a random star, we cannot set any lower bound on the probability that life is out there on the stars we see.
- kibwen 3y agoA good and accessible video on this topic: https://www.youtube.com/watch?v=uzkD5SeuwzM https://www.youtube.com/watch?v=uzkD5SeuwzM
- taneq 3y agoSo it’s a fancy skybox. ;)
- dougmwne 3y agoOne that functions as the greatest physics experiment we could never run and has revealed countless laws of the cosmos, yes!
- johncessna 3y agoWild, I've def heard of some reasons how the Fermi paradox could be resolved, but I missed this explanation. A quick headline scan of the wiki article also doesn't mention it. [1] You'd think that 94% of the observable universe not being reachable would get more of a mention. Granted, we can still look for artifacts such as radio signals or something similar, but it does seem to cut out why a type 3 civ hasn't shown up at our door. [1] https://en.wikipedia.org/wiki/Fermi_paradox https://en.wikipedia.org/wiki/Fermi_paradox
- andrewflnr 3y agoThat's because it doesn't bear on the Fermi paradox at all. The Fermi paradox is about how information from/about aliens could have reached us in the past, whereas GP's comment is about how information from/about us could reach aliens in the future. Very different questions. Put another way, the mere fact that we can see the 94% of future-unreachable galaxies means they're a problem for Fermi, regardless of whether we can signal to them.
- deepsun 3y agoAs one sci-fi writer said, for all the epic space operas ever written and all huge fictional empires ever imagined, they all would fit into just one little border of our Orion Arm (or Local Arm) of Milky Way. There's more than enough of everything.
- wruza 3y agoWait, what? SG:U is about multiple galaxies. Pretty sure many operas also use at least that setting. That writer may have talked about pop-scifi where “something something galaxy” is a best spot for a “wow”, given that on average people don’t know how space is structured beyond that.
- cthalupa 3y agoI believe the comment is more about the practical reality of it - I can say that I have a story that takes place across the whole universe, but if the scenes only take place in a handful of planetary systems, even if I say they're in different galaxies, it could all fit in a tiny fraction of a single galaxy.
- pfdietz 3y agoMy favorite Fermi-friendly space opera setting would involve panspermia in the Sun's natal cluster. This would suppose origin of life in that cluster (not necessarily in our solar system), very soon after star formation, followed by seeding of the other star systems there. This would end up with about 10,000 lifebearing star systems, spread in roughly a half circle around the center of the Milky Way, with our solar system somewhere on that arc.
- deepsun 3y agoThey meant that there's never any need to call it "multiple galaxies", except for wow effect, it would always fit into Local Arm, no matter how big the imagination went.
- its_ethan 3y agoThis is basically the premise to the Fermi paradox: https://en.wikipedia.org/wiki/Fermi_paradox https://en.wikipedia.org/wiki/Fermi_paradox And more specifically the Drake equation (a subsection of the wikipedia article). I personally think anyone's "answer" to the paradox just reveals their personal opinion/ what they want to believe, rather than any meaningful result from data.
- blfr 3y agoThis question has been (very unsatisfyingly) answered, or at least resolved: > When the model is recast to represent realistic distributions of uncertainty, we find a substantial probability of there being no other intelligent life in our observable universe, and thus that there should be little surprise when we fail to detect any signs of it. https://arxiv.org/abs/1806.02404 https://arxiv.org/abs/1806.02404 SSC has an article on the paper as well https://slatestarcodex.com/2018/07/03/ssc-journal-club-dissolving-the-fermi-paradox/ https://slatestarcodex.com/2018/07/03/ssc-journal-club-disso...
- JohnMakin 3y agoUnfortunately this conclusion leads to Boltzmann brains, which isn’t very fun.
- its_ethan 3y agoThis isn't a satisfying resolution at all, it's akin to someone saying "I disagree with the value you used for X, it should be __ instead" - which is basically what I said: it reveals their personal opinion/ what they want to believe. The article says they "incorporat[e] models of chemical and genetic transitions on paths to the origin of life" -- I'm not an expert but that sounds like the territory of some very unsettled science.
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- Octoth0rpe 3y agoI don't think there's been a significant increase in the estimated # of galaxies lately. Identifying clusters is really about identifying areas of higher density that form some cohesive unit, rather than an increase in the actual count of galaxies.
- TechBro8615 3y agoThe universe is unfathomably big. Some hazy but AFAIU relatively accurate napkin math suggests that there are more stars in the universe than there are grains of sand on all of Earth's beaches. But at the same time, there are more molecules in ten drops of water than there are stars in the universe. https://www.npr.org/sections/krulwich/2012/09/17/161096233/which-is-greater-the-number-of-sand-grains-on-earth-or-stars-in-the-sky https://www.npr.org/sections/krulwich/2012/09/17/161096233/w...
- brummm 3y agoThere is other live with almost 100% certainty in the universe. The number of galaxies, stars and planets across the whole universe is just too large for this not to be true. The thought that humans might be the only life in the universe to me seems like the 21st century equivalent of believing earth is the center of the universe.
- htss2013 3y ago>The thought that humans might be the only life in the universe to me seems like the 21st century equivalent of believing earth is the center of the universe. Or it's an acknowledgment of the posterior data that has arisen over the past 30 years. Every human has a camera 24/7 now and no one has documented visitors. Countless new missions and sensor arrays have found no evidence of life anywhere. That doesn't prove no life, but it does make it more likely that the Drake equation is based on assumptions that are fundamentally flawed. Otherwise the Fermi paradox wouldn't still be a paradox. Maybe it's all a simulation. Maybe it's something from a completely different paradigm. Who knows. But insisting they're out there as more decades pass with none found...that may be the real insistence that the sun revolves around the earth.
- IanCal 3y agoThere being life somewhere in the universe and something coming to visit here are wildly different things though.
- wolfram74 3y agoThat there is no complicated life in Sol system besides on earth, or even within 50 light years of Sol system, and that there is complicated life in other parts of the universe are easily mutually compatible facts. Considering our search exhaustive at this point is selling the size of the universe short. We'll likely never interact with extra terrestrials, but it's silly to assume they're not out there.
- Simon_O_Rourke 3y ago> Every human has a camera 24/7 now and no one has documented visitors. Take a few minutes to listen to Prof. Robin Hanson talk on this very thing. https://youtu.be/cQq2pKNDgIs https://youtu.be/cQq2pKNDgIs The jist of what he says, is that there's very much weird stuff seen in the sky, like the McMinnville photos [1], but there's nobody as yet landing a craft on the White House lawn and posing for the cameras. He puts forward a model for this kind of scenario, it's worth a listen, that any visitors would quite rightly be far in advance of the societies we currently live in, and may only show themselves fleetingly so we gain an acceptance of their presence. [1] https://en.m.wikipedia.org/wiki/McMinnville_UFO_photographs https://en.m.wikipedia.org/wiki/McMinnville_UFO_photographs
- Tommstein 3y agoHow could that do anything but increase the chance?
- dougmwne 3y agoIt seems scientifically implausible that we are alone. I base this on a few things: Life started on Earth almost as soon as the surface was cool enough to support it. The surface seems to have been stable enough for life by 3.8 billion years ago, and we have some weaker evidence of life at 3.7 and stronger at 3.5. At any rate, based on what we can observe, life began relatively early and so it seems that as soon as the basic building blocks and preconditions are present, life evolves. We now know that exoplanets are extremely common. Based on observations we can estimate that about 40% of stars have planets, but that’s just what we’ve been able to observe. There are a lot of stars in our galaxy, 100-400 billion. And a lot of galaxies in the observable universe, 200 billion to 2 trillion. And that’s just the observable universe based on our local light cone. For all we know, there could be an infinite number of galaxies. So we have n=1 where life started right away, and perhaps 10^25 planets in the observable universe. That’s a lot of rolls of the dice! Hence the need for a proposed great filter that explains why we don’t get a visitor ever other week. Complex multicellular life seems like a possibility, that took quite awhile, a few billion years before the Cambrian explosion. Complex intelligence also took awhile, resulting in only us after 3.5 billion years of life. And yeah, given that we haven’t been around all that long and seem well on our way to destroying ourselves, seems like complex society could be a great filter too. But space is vast, EM signals attenuate quickly and the speed of light is a harsh mistress. They are probably out there, but we’ll probably never meet them.
- lazide 3y agoUh, we don’t necessarily need a great filter to not be constantly visited - we just need a lack of ‘cheat codes’ (like warp drives, wormholes, dirt cheap energy from magical fusion or zero point or whatever), combined with relatively short lived complex civilizations. If no one can afford the trip (due to what we currently know of physics), or survive as a complex civilization long enough (100k+ years), then… you see what you see right now.
- dontupvoteme 3y agoIf you're talking about sending live people, absolutely If you're talking about sending alien drones, the light mass and lack of having to keep them alive makes energy requirements a lot lower, but they'd probably just be scouting us (if not trying to kill us) so we wouldn't be able to detect them
- russdill 3y agoThe more galaxies we can see, the more lack of evidence we have for any large scale changes to the universe by any intelligence. Many people take this as an indication that there is no other intelligent life or life of any kind in our observable universe. Also see: grabby aliens.
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- uejfiweun 3y agoThere's a part of me that thinks that life represents a key property of the universe, one that we may see accelerate drastically in our lifetimes. All around the universe we see entropy (in a broad sense) - the turning of order to disorder, the fundamental march toward the eventual heat death of the universe. But life is the one thing we're aware of that actually trends toward increasing order - starting with unicellular organisms, then the cambrian explosion, then the evolution of humans, then our highly advanced and organized societies... and now we're on the cusp of inventing AI. An invention that, as Kurzweil puts it, could eventually turn all the matter into the universe into a giant computer of sorts and use it to simulate another universe. I don't know, if you ask me, this represents some sort of fundamental force, or constant, or thing, that we haven't quite gotten to the bottom of yet. Some property of the universe that simply trends toward increasing complexity under specific conditions.