Sadly it may be the speed of light.
All these intelligent species are simply trapped in their own solar systems for all eternity by an unbreakable natural law.
1) Be nice and; have fun
Doxxing, trolling, sealioning, racism, and toxicity are not welcomed in AskLemmy. Remember what your mother said: if you can't say something nice, don't say anything at all. In addition, the site-wide Lemmy.world terms of service also apply here. Please familiarize yourself with them
2) All posts must end with a '?'
This is sort of like Jeopardy. Please phrase all post titles in the form of a proper question ending with ?
3) No spam
Please do not flood the community with nonsense. Actual suspected spammers will be banned on site. No astroturfing.
4) NSFW is okay, within reason
Just remember to tag posts with either a content warning or a [NSFW] tag. Overtly sexual posts are not allowed, please direct them to either [email protected] or [email protected].
NSFW comments should be restricted to posts tagged [NSFW].
5) This is not a support community.
It is not a place for 'how do I?', type questions.
If you have any questions regarding the site itself or would like to report a community, please direct them to Lemmy.world Support or email [email protected]. For other questions check our partnered communities list, or use the search function.
Reminder: The terms of service apply here too.
Logo design credit goes to: tubbadu
Sadly it may be the speed of light.
All these intelligent species are simply trapped in their own solar systems for all eternity by an unbreakable natural law.
But surely generational ships would get us over that?
AFAIK there is no known energy source that would keep a generation ship powered for the duration of an interstellar flight.
The person to whom you responded is half right. The speed of light is half of the barrier to interstellar travel. Entropy is the other half.
Would you need a power source? If you aim your ship correctly, then put everything alive into cryo, the ship could go completely dark, vent all heat and become a frozen rock. Then after [very long time] the ship enters the vicinity of a different star and can be reactivated and unfrozen using solar energy. You dont need energy to maintain cryo if the whole ship is at 1° kelvin.
(Of course that relies on cryo sleep being possible)
Not really, no. Generational ships might make colonizing the nearest star systems possible, but even colonizing our own galaxy would require some kind of suspended animation. The milky way is between 100,000-200,000 light years in diameter so even at the speed of light, you're looking at a travel time that is ~33-66% of the time that humanity has even existed(homo sapiens are currently estimated to have become a distinct species 200,000-300,000 years ago)... just to go to ONE star system out of the hundreds of BILLIONS that exist in our galaxy. You're gonna need generational ships so self-sustaining and capable that the generation that actually arrives at the destination will have long forgotten the point of the trip and might not want to leave the comfort of the ship.
Still, colonizing our own galaxy is at least theoretically possible, given enough time. The real filter is just how unimaginably large the universe is. The vast, VAST majority of the observable universe is FOREVER out of our reach, as it is expanding away from us faster than the speed of light. Then there's the unobservable universe, which could literally be infinitely bigger than the observable universe for all we actually know.
That's why faster than light travel is the holy grail. Without it, we're just kind of stuck.
Imagine if wormholes had zero constraints on the physical location of the other side of the wormhole though. We could open a portal to OUTSIDE the observable universe. What a mindfuck. We might even find a false vacuum decay racing towards us at the speed light, or regions of space that are contracting instead of expanding, or initiate a new big bang by opening a wormhole to an area of space where that hasn't happened...we could travel to a point where we can watch the milky way get formed, since the light of its formation is just reaching that region of space. If it turns out the heat death of the universe is just a local phenomenon, we could continue expanding forever beyond it. World without end.
I think that the great filter/fermi paradox is a combination of two facts,
They're not missing or gone, they've just moved beyond messy radio signals. Even we tightened up our radio emissions in a little over a century. Most of what we watch or listen to comes to us via fiber, cable, or short range transmissions like cell phone towers and Wi-Fi.
My favorite filter is the amount of phosphorous in the universe. Earth has an unusually high amount, and it's vital for life. I like this one, because as more stars die, the amount of phosphorous goes up, implying we won't be alone forever.
Anyway, look up "Issac Arthur" on YouTube for HOURS of content about the Fermi paradox and potential great filters.
I'm gonna add to this by saying phosphorus may be my favorite, but I think the most likely filter is just time, twice.
Do you know how unlikely it is that earth has been habitable for so long? Do you know how long life was single-celled? One of the theories for how advanced (eukaryotic) cells formed was the combination of at least three different branches of life into the same cell! Archaea (cell wall), bacteria (mitochondria/chloroplasts), and viruses (nucleus). Do you know how unlikely that sounds? Do you know how long it would take for that to happen randomly? Most planets probably aren't even habitable for that long. Once we became eukaryotic, we started progressing much faster.
Then, keep in mind, the life has to continue to exist for billions of more years while it waits for the advanced life to happen again within the same section of the galaxy. So, time is two filters - both behind us and in front of us.
An alternative is we are among the first. Third generation stars are the ones that have planets with enough heavy elements to allow for complex chemistry. Sol (our star) is thought to be among the first batch of third generation stars in our gallexy.
Light speed does seem to be the upper speed limit for the universe. Talking that into account we probably haven't had a chance to see other early life as it would likely be spread pretty thin right now.
Yeah, I have a gut feeling that a lot of the variables in the Fermi equation are a little too generous.
This is my favorite, mainly because it's been well argued by some respectable scientists.
Another is that we're in a simulation, and aliens aren't part of it. There are also some very good statistics pointing to the simulation theory, from just sheer scale.
I do agree that in the grand scale of things we're actually very early. That alone would explain a lot.
Honesty, I don't think that there is a Great Filter. The Fermi Paradox strikes me as not very well-reasoned. A whole hell of a lot of things would have to go exactly right for civilizations to make contact, rather than it being the default assumption. There are lots of filters, not just one Great one.
But the closest to a Great Filter is that space is really, really. stupendously big. The chances of even detecting each other across such distances is vanishingly small, much less traversing them. Add in the difficulty of jumping the metabolic energy gap to become complex life, and that could reduce the density of civilizations down to a level that they're just not close enough to each other in spacetime to admit even the possibility of contact. And we're hanging our hat on some highly-speculative concepts like alien mega-structures harnessing whole solar systems to allow detection.
I think a lot of persnickety, smaller filters combine to make interstellar contact between civilizations against long odds. Perhaps the best we'll get is spectral signatures from distant planets that are almost-conclusive proof of some sort of life.
Probably too optimistic and unhinged, but maybe a species advanced enough for interstellar travel, building mega structures etc. are advanced enough to ascend to a higher plane of existence or alternate dimensions or whatever. Maybe there's some alternative to this reality that will be unlocked by advanced technology that made all advanced life prefer that, to here.
That's a really neat idea I've never heard before. Like, maybe our entire universe is analogous to the ocean floor sea-vents that life arose out of. Cold, and dead, and boring, and difficult. And one day we'll discover how to ascend.
We're currently in it. Failing to create a clean, renewable, and scalable energy source powerful enough to run a society that is ever increasing in both population and technology without destroying their only inhabited planet has got to be the most common great filter.
Asteroids strikes, super volcanoes, solar CMEs, and other planetary or cosmetic phenomena that exactly line up in both severity and timing are too rare IMO.
Every society that attempts to progress from Type 1 to Type 2 has to deal with energy production. Most will fail and they will either regress/stagnate or destroy themselves. Very few will successfully solve the energy problem before it is too late.
A filter for sure, but not a great one. Call me optimistic, but I don't think that will set us back more than 10.000 years. If humanity can survive, society will re-emerge, and we are back here 2-3000 years into the future.
Is +5°C Earth a good place to be? No. Will the majority of humans die? Absolutely. Will the descendants get to try this society thing again? I believe so.
On a cosmic scale 10.000 years is just a setback, and cannot be considered a great filter.
Everyone is talking about society or physiology stuff. That is just things that might get humans.
Stars going super-nova is the real great filter. Our sun is 4.6 billion years old. Life started 4 billion years ago. In 4 billion years, the sun goes supernova. We are halfway to the end of the earth.
Smaller stars last longer, but have smaller ranges that life can exist in - and planets tend to move in or out in their orbits. Bigger stars have giant habitable zones - but some large stars born when humans took their first steps are in their last decades of life. You couldn't get from the pyramids to NASA in that time, never mind the 4 billion years it took to get to humans.
I think it's supposed to actually less than that, the sun's luminescence will increase over the next 1 billion years to the point that it will boil off the earth's oceans. No life will be able to exist past that, and earth will just be a barren rock in orbit for the next 3 billion years.
I don't think there is a single filter. My personal gut feeling however is that the jump to "specialised generalists" would be a major hurdle.
Early human civilizations are very prone to collapsing. A few bad years of rain, or an unexpected change of temperature would effectively destroy them. Making the jump from nomadic tribal to a civilisation capable of supporting the specialists needed for technology is apparently extremely fragile.
Earth also has an interesting curiosity. Our moon is extremely large, compared to earth. It also acts as a gyroscopic stabiliser. This keeps the earth from wobbling on its axis. Such a wobble would be devastating for a civilisation making the jump to technological. Even on earth, we are in a period of abnormal stability.
I suspect a good number of civilizations bottleneck at this jump. They might be capable of making the shift, but get knocked back down each time it starts to happen.
Speaking of our moon, the fact that it's roughly the same size as the sun as seen from earth and the fact that this is a complete coincidence blows my mind. Like there's no reason for that to be the case. Total eclipses like ours (where you can see the corona) are very rare.
Earth also has an interesting curiosity. Our moon is extremely large, compared to earth. It also acts as a gyroscopic stabiliser. This keeps the earth from wobbling on its axis. Such a wobble would be devastating for a civilisation making the jump to technological. Even on earth, we are in a period of abnormal stability.
There seem to be so many coincidences that make our solar system unique that it's really upsetting lol It's like we are so perfect for stability because of things like Jupiter keeping the inner system "clean" of large impactors, our part of the galaxy being more "quiet" than typical as far as supernovae, stuff like that which makes it seem even less likely for life to exist anywhere else. :(
My thought is the evolution of intelligent life itself. If you think about it, intelligence is contrary to most of the principles of evolution. You spend a shit ton of energy to think, and you don't really get much back for that investment until you start building a civilization.
As far as we can tell, sufficient intelligence to build technological civilizations has only evolved once in the entire history of the Earth, and even then humans almost went extinct
Boy, Lemmy sucks donkey dick. For every one legitimate answer there are two or three edgelord answers like "capitalism" and "the internet".
Here's an answer that hasn't come up yet: cooperation among mono cellular organisms. I don't mean the development of polyp analogues or colonies of single celled organisms; I mean getting down to mitochondria. Brace for wild oversimplification.
Before mitochondria, life had a hard time creating enough energy to do much more than barely stay alive. The current line of thinking is that one organism ate another and didn't digest it. The two organisms worked symbiotically, one handled energy production and the other handled getting food and staying alive.
Just about every living thing utilizes mitochondria and if the current idea that mitochondria were actually symbiotic organisms is true, that means that what was likely a chance "sparing" of prey is the underpinning of all complex life.
The odds of that happening are ridiculously low. There could be simple life in tons of places even within our own star system, but if the mitochondria-like symbiotic capture never happens for those extraterrestrial organisms, then complex life is probably unlikely to develop.
I like the “Dark Forest” theory I learned from the Three Body Problem books. Basically it’s dumb for civilizations to make a big footprint and reveal themselves because other civilizations won’t know how powerful and dangerous you might become, and so out of precaution they might just zap you. Ironic and over dramatic, but just because that’s a possibility it might be wise to keep a low profile and not invite trouble.
The "Dark Forest" is fine for a scary sci-fi series, but it has many flaws that make it unrealistic as a real solution to the Fermi paradox.
It may very well be republicans
Howabout a reasonably advanced civilization destroying itself and its homeworld after exploiting and then running out of petroleum?
There is a great video about the Great Filter by Kurzgesagt/In a Nut Shell. If I remember correctly, in it they say we can guess at which stage the filter is by how evolved extraterrestrial life forms are. So it's actually great if we find a lot of bacteria or other primitive life forms, that would mean we probably already have overcome the Geat Filter on Earth. On the other hand, if we find many alien ruins of several civilizations at or above our technological level... Well, our greatest challenge might be coming.
We have had Millions of years of (presumably) intelligent Dinosaurs on this planet, but only 200.000 years of mankind were enough to create Civilization IV, the best Strategy game and peak of life as we know it.
So clearly, Civilization™ is what sets us apart.
Jokes aside, the thing evolution on earth spend the most time on is getting from single celled life-forms to multicellular life (~2 billion years). If what earth life found difficult is difficult for all, multicellular collaboration is way harder than photosynthesis, which evolved roughly half a billion years after life formed.
I would say it's the size of the universe and the fact that it is still expanding at an accelerated rate.
If the speed of light is really the "top speed" of the universe, it is inadequate for interstellar travel. It is barely good enough for timely communication, and not really even that.
Life can be as likely as it wants to be, but it seems to me that we're all quite divided, to the point of not being able to communicate at all with other potential intelligent species.
For a technological civilization like ours, I think it’s just that Earth/humans are weird and we’re past the main ones (like going from single-cell to multi-cellular organisms).
Having to overcome the physical obstacles on other planets rules out the type of spacefaring technological civilizations like ours. No matter how intelligent a civilization on a water world is, it’s not starting fires, much less building rockets. Just getting out of the water would be their space program. Even a totally Earth-like planet that’s a bit bigger and has an intelligent species wouldn’t be able to get to space with chemical rockets.
And also, humans are weird. It could be as basic as “we have hands for building complex tools.” We have a seemingly insatiable need to compete and explore, even beyond all logic—maybe no other intelligent species wants to strap someone to a rocket and send them to space because it sucks up there. We’re violent: without WWII and the Cold War, do we even have a space program?
So many things had to come together to create an intelligent, tool-building species with hands that lives on a planet with the right balance of land and water. As far as we know, it never even happened on Earth before and even then, we had thousands of years of civilizations before anyone was dumb enough to strap themselves to a rocket just to see what would happen.
Honorable mention: we haven't detected alien probes, because intelligent alien societies haven't begun consuming the galaxy with exponential numbers of self-replicating robotic probes, because that's just a really bad idea:
Simple workarounds exist to avoid the over-replication scenario. Radio transmitters, or other means of wireless communication, could be used by probes programmed not to replicate beyond a certain density (such as five probes per cubic parsec) or arbitrary limit (such as ten million within one century), analogous to the Hayflick limit in cell reproduction. One problem with this defence against uncontrolled replication is that it would only require a single probe to malfunction and begin unrestricted reproduction for the entire approach to fail – essentially a technological cancer – unless each probe also has the ability to detect such malfunction in its neighbours and implements a seek and destroy protocol (which in turn could lead to probe-on-probe space wars if faulty probes first managed to multiply to high numbers before they were found by sound ones, which could then well have programming to replicate to matching numbers so as to manage the infestation).
It's gotta be the development of what we recognize as "intelligent". Our brains are not the goal of evolution, just a weird thing that happened.
My suspicion is that it's abiogenesis, but it's only a suspicion that I can't have any certainty of
The most boring one: most species off themselves before they fully get off their starting planet. We will go the same way. Take your pick from climate change, war, pandemic, ... or even a combination of several!
Even if you had a super intelligent species that can make Dyson spheres and travel at the speed of light the observable universe is beyond vast. I don't know much about cosmology or our ability to detect light but given humans have only been looking into the sky for a couple centuries, not being able to see a thimble in the ocean seems like a non issue. I think if you scale the observable universe down to the size of earth the speed of light becomes 0.05 mph.
I read an article about Fermi paradox (I cannot find the link) that stated the humans are one of the first intelligent beings in the universe. That's why we haven't encountered any green men so far. We just might came too soon to the party.