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[cormack12]

Brian Cox explains the Fermi Paradox and the Great Filter Hypothesis, which could be a key solution to the Fermi Paradox. Brian Cox goes into great detail about the Fermi Paradox, offering explanations for why we have not yet seen evidence of intelligent alien civilizations, even though our galaxy, the Milky Way, contains billions of planets that could support life as we know it.

One possible explanation Brian Cox discusses is the Great Filter, a theoretical barrier that could drastically limit the number of civilizations capable of expanding beyond their home planets. This could mean that life itself is rare, intelligent life is even rarer, or that technological civilizations tend to self-destruct before they reach the stage of interstellar communication.

 

[rm082e]

It's one of more than a dozen explanations. Personally, my gut tells me:

1. Planets around Red Dwarf stars probably aren't a very good place for life to flourish. The more we learn, the worse the odds get. Red Dwarfs are 74% of all main sequence stars. Only 7.5% are yellow dwarfs like our sun. On top of that, something like half of all stars are in a multi-star system, which makes it less likely that a planet will have a stable orbit in the habitable zone for the billions of years required for life to evolve into a space-faring civilization. As a result, I think the "hundred billion" number that gets thrown out for the Milky Way is very misleading in terms of communicating the number of stars that might be able to host life.
2. Given we don't see aliens everywhere, it seems obvious to me that abiogenesis is likely very rare, and/or the evolution from simple single-celled life into complex life is very rare. It would be really surprising if single-celled life were common place, but complex life is the crazy high odds.

I don't buy the zoo, dark forest, or simulation explanations.

 

[Tams]

It's one of more than a dozen explanations. Personally, my gut tells me:

1. Planets around Red Dwarf stars probably aren't a very good place for life to flourish. The more we learn, the worse the odds get. Red Dwarfs are 74% of all main sequence stars. Only 7.5% are yellow dwarfs like our sun. On top of that, something like half of all stars are in a multi-star system, which makes it less likely that a planet will have a stable orbit in the habitable zone for the billions of years required for life to evolve into a space-faring civilization. As a result, I think the "hundred billion" number that gets thrown out for the Milky Way is very misleading in terms of communicating the number of stars that might be able to host life.
2. Given we don't see aliens everywhere, it seems obvious to me that abiogenesis is likely very rare, and/or the evolution from simple single-celled life into complex life is very rare. It would be really surprising if single-celled life were common place, but complex life is the crazy high odds.

I don't buy the zoo, dark forest, or simulation explanations.

What makes it so hard to know is that the universe is just so huge and increasing.

Almost every viable planet for life that we know of is a small dot on a light spectrum we can't even see ourselves. So to even send the message that your spacefaring species exists is incredibly hard. It might even be impossible.

Then there's the possibility that most life never manages to get past key milestones. Some might even be conscious of their ownn condition, but have never gotten past a perpetual state of conflict and war.

I reckon there are/have been a fair few other planets with spacefaring civilisations out there, somewhere, but that to come into contact with each other before they collapse (self-destruction or their star 'dying') is so remote, and that travelling fast enough to negate those issues is impossible.

 

[rm082e]

What makes it so hard to know is that the universe is just so huge and increasing.

Almost every viable planet for life that we know of is a small dot on a light spectrum we can't even see ourselves. So to even send the message that your spacefaring species exists is incredibly hard. It might even be impossible.

Then there's the possibility that most life never manages to get past key milestones. Some might even be conscious of their ownn condition, but have never gotten past a perpetual state of conflict and war.

I reckon there are/have been a fair few other planets with spacefaring civilisations out there, somewhere, but that to come into contact with each other before they collapse (self-destruction or their star 'dying') is so remote, and that travelling fast enough to negate those issues is impossible.

Sure, but it's even easier than that - we're probably never going to be able to detect any signs of life in another galaxy. Even if we built the largest telescope we could theoretically build in space and keep functional, we're probably not going to get a high enough resolution to conclusively identify life. Andromeda is the closest, and it's 2.5 million light years away. Even if we assume we could one day develop technology that could detect a planet orbiting a star there, we'd be seeing it as it was 2.5 million years ago.

Our only real hope is to find life in the Milky Way, and relatively close to us (within a few tens of thousands of light years). If we don't find something just "down the street", then it doesn't really matter if there's life in other galaxies. It will be so far away we won't know about it or be able to interact with it. We will remain all alone from a functional perspective.

 

[Zathalus]

There can literally be a billion sapient alien species out there and due to how fucking huge space is we might be the only one in our galaxy, or even local cluster.

 

[Dr_Ifto]

Space is huge. Its really huge. Traveling from one star to another just would take too long or any civilization to do.

 

[sono]

Shallow and nothing new quite honestly. For example he didn't explain the reason WHY any civilisation would go to the effort to build self replicating space faring machines. For example.. is it to slowly find habitable planets or those with life and send a a message slowly home ie hoping you eventually get a message saying look here? The builders won't be around to get the answer so the cost would have to be driven by some noble collective aim to find out the answer for future folk. Can't see any government approving that expense!

He didn't mention traversing the galaxy is hard due speed limits.

He didn't mention dark forest theory but instead assumed that to be space faring you would need to conquer agression and be nice... lol

 

[RagnarokIV]

He looks like the keyboard player from Dare

He didn't mention traversing the galaxy is hard due speed limits.

Mate nevermind the galaxy, it's hard enough traversing the estate driving on me way home from the pub. 20mph, 30 mph, 40 mph... up and down all the bloody time. Hard to keep track when you've had a few

 

[AJUMP23]

When it comes to intelligent life we are it. And even that is suspect.

 

[Hookshot]

How may planets have the conditions for life, plus large amounts of fossil fuels and an atmosphere full of a gas that allows the burning of the fuels to even have an Industrial Revolution?

 

[Three]

How may planets have the conditions for life, plus large amounts of fossil fuels and an atmosphere full of a gas that allows the burning of the fuels to even have an Industrial Revolution?

If there is abundant life there would likely be fossil fuels, no?

 

[Hookshot]

If there is abundant life there would likely be fossil fuels, no?

Presuming they have plate tectonics or some other geological process to bury them, convert them and put them back in an accessible place instead of destroying them. And that the life is made out of the same things as here.

 

[Cyberpunkd]

Mate nevermind the galaxy, it's hard enough traversing the estate driving on me way home from the pub. 20mph, 30 mph, 40 mph... up and down all the bloody time. Hard to keep track when you've had a few

Please don’t tell me you just admitted to driving under influence?

 

[cormack12]

I find it stranger to think about Earth dying. Like, if we take at face value we are the only life, then what is the point of the Universe if there is no life? There would just be this vast space of various planets, stars and moons that exist for no real reason.

That concept blows my mind more tbh.

 

[violence]

A long time ago when I was on Facebook, a girl posted a video of this guy cause she thought his “brain” was attractive. I commented, “I didn’t realize how much you liked Cox.”

 

[Hookshot]

There would just be this vast space of various planets, stars and moons that exist for no real reason.

That concept blows my mind more tbh.

Gets even stranger when you think that it's always been that way. Even if the Big Bang 100% happened like we think, there was still something before to cause it. Yet we have no idea what or why to any of it.

 

[RagnarokIV]

Please don’t tell me you just admitted to driving under influence?

Alright RoboCop, I'll make sure I get an attorney next time I post when you're online

 

[Liljagare]

 

[Chittagong]

I go with the Dark Forest hypothesis, it makes most logical sense.

 

[Badlucktroll]

i bet you need an earthlike planet in the exact place that our earth is in, and a star in the exact place the sun is in, and all the right chemicals too. its pretty simple really. i bet that trappist 1 system is all fucked up because they orbit a red dwarf, with hot ass airless planets and the front and iceballs at the back and tidally locked fucked up venuses in the middle. then again, it probably happened somewhere else, sometime, but they are too far away in space and time for us to meet.

 

[EverydayBeast]

Because of the angles, a galaxies goal should be life. Lack of any life (insects, fish etc.) in other planets across the galaxy and universe troubles scientists.

 

[LordCBH]

The fact that we haven’t been contacted proves to me that intelligent alien life exists. I wouldn’t contact us either.

 

[Hookshot]

The fact that we haven’t been contacted proves to me that intelligent alien life exists. I wouldn’t contact us either.

There's no chance we'd play nice with others. Unless it was something daft like they were a billion years more advance, we'd figure out their tech almost instantly and once we spread that's it, it's the world all over again but on a universal scale.

 

[Hawk The Slayer]

Because they are actually demons/fallen angels.

Alistar Crowley summoned a demon a long time ago and that demon looked like one of those grey aliens that's popular in media.

 

[kevboard]

the most likely explanation is so simple...

the Universe is huge, and in order to get to a civilisation like ours a shitload of random things have to go right over the cause of millions of years.
and even tho this all went right for us, even we can't roam the universe yet.

the fact that we even evolved into a species that can think the way we do is extremely random and probably super rare.
there's no unique evolutionary benefit for our intelligence, it just happened to go down that route and we managed to survive, yet we are the only species on our planet to have this capability, with our closest related animals maybe reaching the mental capabilities of a human toddler.

intelligence is not necessary to be evolutionarily successful. the most successful species on our planet are among the dumbest organisms possible. they are barely sentient... your phone's AI assistant is probably more sentient than most insects.
they just run a simple routine, no individual thoughts in sight, like preprogrammed machines.

so everything that has to go "right" for advanced civilisations to exist is far more insane than many seem to take into account.

and not only that! it also has to happen close enough to us for them to even realistically be noticeable, AAAND they have to exist at the same time as us, and be already sophisticated enough to make themselves noticeable for us.

so a shitload of random things have to go right to get to our level.
it has to go right close enough to us to notice.
and it has to happen at the same time as our existence lasts.

that's like winning 100 lotteries in a row...

 

[Bumblebeetuna]

 

[willothedog]

intelligent life out there? One can only D:Ream.

 

[crazepharmacist]

Clearly far superior intelligent life exists in the universe if you are to believe the tic tac video released by the pentagon is not somehow technology from China or Russia.

In my opinion, If China or Russia did have technology that defied the laws of physics back in 2004 when the footage was captured, I think we would all be speaking a different language right now.

 

[Superkewl]

Am I the only one who came here thinking it was going to be the actor who was going to be explaining the theory?

 

[qbxwhi]

too far away.

 

[Kenpachii]

We exist, so high chance there is more of us somewhere else.

 

[Bert Big Balls]

No matter how many times I hear this explained, I can't shake the feeling that there is something out there. Whether it be intelligent life or just microbial, there has to be something.

Just because we haven't heard anything yet, doesn't mean there is nothing out there. The universe is just so unbelievably enormous, the distances so vast, that it's entirely possible that some civilization 1 million light years away discovered they could send radio signals 500,000 years ago, meaning it's still going to take another 500,000 years to even get to us. That is, if we can even pick it up due to the distance travelled and the inverse square law. The signal would be degraded so much that we likely wouldn't be able to even detect it.

Or, there could be life 90 billion lightyears away, meaning there is just no way we'd ever receive anything over such a vast distance. If they sent something 12 billion years ago, it's never reaching us. The earth could be gone in 5 billion years or so once the sun says "fuck this shit" and nukes itself.

This is all assuming that these beings use the same communication methods as us. We can't assume that another group of lifeforms took the same path we did. They could be communicating via channels we don't even know about, or perhaps they have no interest in entertainment or communication over distance so things like radio / tv etc just aren't used. We literally don't know, because we've not found anything, so it annoys me when I see people just assume so much stuff and use that as fact to say "well we would have found them by now." - well, you can't prove that, and we need to be open to the fact that there may be something out there.

Love Brian Cox, but not a fan of this paradox and never will be.

 

[T8SC]

The one thing the BBC tends to do well, is it's science documentary series and Brian Cox's series are always worth a watch.

 

[clem84]

I saw this not too long ago.

This is the great filter and the reason why we haven't been visited by anyone. Basically outer space is so gigantic, and so inhospitable to life that interstellar space travel is virtually impossible.

 

[clarky]

Rule number one:

Never trust a guy who played keyboard in D:REAM.

 

[Brakum]

Fermi paradox is bullshit. It's like saying i took a glass of water from the ocean, where are all the fish if they exist?

 

[SimTourist]

I find it stranger to think about Earth dying. Like, if we take at face value we are the only life, then what is the point of the Universe if there is no life? There would just be this vast space of various planets, stars and moons that exist for no real reason.

That concept blows my mind more tbh.

There is no point to it, it just exists, the scale is mindblowing though, just a massive fucking ball of hydrogen beyond our comprehension and our sun is already pretty damn big and even this big bastard will die eventually

 

[ClanOfNone]

Fermi paradox is bullshit. It's like saying i took a glass of water from the ocean, where are all the fish if they exist?

I agree.

I’m also puzzled when I hear people say only certain types of planets can support life. Life as we know it?
What about my Sylandro gas people? Or the silicon based Chenjesu? Star Control 2 references aside, why do most people assume that life that evolves elsewhere under drastically different conditions will be in any way similar to us. An infinite universe contains infinite possibilities.

 

[Trilobit]

And we won't ever find any. Earth is unique in that it has life.

 

[mopspear]

It's one of more than a dozen explanations. Personally, my gut tells me:

1. Planets around Red Dwarf stars probably aren't a very good place for life to flourish. The more we learn, the worse the odds get. Red Dwarfs are 74% of all main sequence stars. Only 7.5% are yellow dwarfs like our sun. On top of that, something like half of all stars are in a multi-star system, which makes it less likely that a planet will have a stable orbit in the habitable zone for the billions of years required for life to evolve into a space-faring civilization. As a result, I think the "hundred billion" number that gets thrown out for the Milky Way is very misleading in terms of communicating the number of stars that might be able to host life.
2. Given we don't see aliens everywhere, it seems obvious to me that abiogenesis is likely very rare, and/or the evolution from simple single-celled life into complex life is very rare. It would be really surprising if single-celled life were common place, but complex life is the crazy high odds.

I don't buy the zoo, dark forest, or simulation explanations.

I'm with you on this one. I don't know if I've heard your first point from anyone else but I've had this thought a number of times. I'd add to the second point that even if a civilization got a head start on us by not too huge a number (in terms of how old the universe is) then they would have spread out so much and so loudly that we should have seen some Dyson Swarms by now. I get the feeling people are assuming these civilizations would be similar to ours but with better space travel when actually they'd be so incredibly large even if they got a head start on us by less than a million years (the universe is much older than that).

 

[Diddy X]

For the statistics to come true you have to have all those billions of stars and planets because the chances are just so low. We are so lucky to be alive it's truly a miracle.

 

[rm082e]

I'm with you on this one. I don't know if I've heard your first point from anyone else but I've had this thought a number of times. I'd add to the second point that even if a civilization got a head start on us by not too huge a number (in terms of how old the universe is) then they would have spread out so much and so loudly that we should have seen some Dyson Swarms by now. I get the feeling people are assuming these civilizations would be similar to ours but with better space travel when actually they'd be so incredibly large even if they got a head start on us by less than a million years (the universe is much older than that).

Here's a good primer on why Red Dwarf stars are probably not a good place for live to develop:

I'd add to the second point that even if a civilization got a head start on us by not too huge a number (in terms of how old the universe is) then they would have spread out so much and so loudly that we should have seen some Dyson Swarms by now. I get the feeling people are assuming these civilizations would be similar to ours but with better space travel when actually they'd be so incredibly large even if they got a head start on us by less than a million years (the universe is much older than that).

Yeah, people don't often take into account the potential for robotics and automation. If we make it another couple of hundred years (seems inevitable to me), then we'll have automated robots mining the asteroids and planets for resources, turning those resources into solar panels, computers, batteries, more robots, space stations, etc. Play that forward a few million years and the growth potential is hard to predict.

 

[JimmyRustler]

Space is huge. Its really huge. Traveling from one star to another just would take too long or any civilization to do.

Wormholes man.
I doubt that we are at our wits end with our current understanding. I know it’s not possible to go faster than light with Einstein’s theory and it makes total sense but I’m sure we’ll find a way to bend space one day - or travel the distances by some other, currently unknown means.

As for the topic… I can’t imagine we’re the only ones out there. Humanity will prolly have a good laugh when they get out there one day for even thinking this.

 

[Major Insano]

For me there are two major barriers for us and ETs.
The distances between stars systems and timing.

We would have to be very fortunate to not only exist, but to have the tech to contact or observe ETs at the same time as them.
It's only been what? 100 years that we've had the tech.
Even if we survive for thousands of years, it's still such a small window in astrological terms.

Who knows how far tech will advance in that time though.
It's likely that we will at least be able to send probes out to the nearest stars by then.

I do like the dark forest theory as well. It's possible that we're being/have been observed or dicovered by now, but not contacted.

Side note: I believe time travel is impossible. At least going backwards.

How can you travel to somewhere that doesn't exist?

 

[kruis]

the most likely explanation is so simple...

the Universe is huge, and in order to get to a civilisation like ours a shitload of random things have to go right over the cause of millions of years.
and even tho this all went right for us, even we can't roam the universe yet.

the fact that we even evolved into a species that can think the way we do is extremely random and probably super rare.
there's no unique evolutionary benefit for our intelligence, it just happened to go down that route and we managed to survive, yet we are the only species on our planet to have this capability, with our closest related animals maybe reaching the mental capabilities of a human toddler.

intelligence is not necessary to be evolutionarily successful. the most successful species on our planet are among the dumbest organisms possible. they are barely sentient... your phone's AI assistant is probably more sentient than most insects.
they just run a simple routine, no individual thoughts in sight, like preprogrammed machines.

so everything that has to go "right" for advanced civilisations to exist is far more insane than many seem to take into account.

and not only that! it also has to happen close enough to us for them to even realistically be noticeable, AAAND they have to exist at the same time as us, and be already sophisticated enough to make themselves noticeable for us.

so a shitload of random things have to go right to get to our level.
it has to go right close enough to us to notice.
and it has to happen at the same time as our existence lasts.

that's like winning 100 lotteries in a row...

And then there's the troublesome issue of what would happen if there's intelligent life out in the universe that's so far advanced they were able to detect intelligent life on our planet and are actually able to contact us. What if they're so far advanced that we're like insects or at best human toddlers compared to these sentient intelligent beings that who think, behave and act in ways that are completely alien to us?

 

[DragoonKain]

The odds of life forming is so unlikely not to mention the odds that life can exist long enough to evolve enough to develop technologically to travel vast distances of space is even more unlikely. Even if you are lucky enough to be an alien life form that develops somewhere which is incredibly unlikely, the odds you can evolve before you're wiped out by an asteroid, a comet, disease/viruses, war, whatever are more unlikely. So as big as the universe is I'm not sure there's life out there. But the universe is fucking huge so it's possible.

And also don't forget there are places in the universe so far away that they could never reach us because they're expanding away from us faster than the speed of light, so a portion of the universe is completely off limits for the ability to reach us. So that narrows down the chances even more because the entire universe isn't even in play.

 

[MrA]

I agree.

I’m also puzzled when I hear people say only certain types of planets can support life. Life as we know it?
What about my Sylandro gas people? Or the silicon based Chenjesu? Star Control 2 references aside, why do most people assume that life that evolves elsewhere under drastically different conditions will be in any way similar to us. An infinite universe contains infinite possibilities.

given how feaky life is around the thermal vents, I think it's safe to assume life could be quite different in other places
a second thought is, our observations of chemistry and physics are all in a tiny spec in the universe over a tiny amount of time. no guarantee our understanding applies throughout the entire universe or that there are forces we haven't discovered or are potentially beyond our comprehension.

 

[Chittagong]

I was diving with some blacktip sharks this morning, looking them eye to eye, and thinking how bizarre it is that they have existed so much longer than humans and basically remained at an unchanged intelligence level. They are close to the apex like humans, but they never gained the social, language, cultural, technical, artistic skills as humans - even though their timeframe is vastly longer.

 

[MilkyJoe]

maybe he hasn't seen any....

 

[Verchod]

But does alien life have to be the same size as us?
It's an odd thought, but could alien life, intelligent life, exist in a smaller scale. I don't mean microscopic but just really small. What is they were similar to us but maybe only a few inches high.