Are we alone in the universe? | Sean Carroll and Lex Fridman

Lex Fridman Podcast full episode: • Sean Carroll: General ...
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GUEST BIO:
Sean Carroll is a theoretical physicist, author, and host of Mindscape podcast.
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[@LexClips]

Full podcast episode: kzbin.info/www/bejne/qpXZaKVof7iioas Lex Fridman podcast channel: kzbin.info Guest bio: Sean Carroll is a theoretical physicist, author, and host of Mindscape podcast.

[@InnovativeInvestmentIdeas]

"Life finds a way". Lex doing his best Jeff Goldblum impersonation.

[@t-rexreximus359]

😂 that jumped out at me too. ‘Did he just quote Jurassic Park to support his point’ 😂

[@Jjjjjjgggg]

personally i find the idea of humans being alone in the universe much more terrifying than aliens existing. we know intelligent life exists in the universe. we don't know if it's happened more than once.

[@funnysapiens]

2:42 what a powerful statement! we should follow that in every aspect of our life.

[@sdmods619]

Distance is the answer. We exist because of this separation of space and time. If we were accessible we would be dead

[@user-vv8oh5kz1w]

I feel like you're probably right

[@mph650]

Gravity manipulation technology to allow for interstellar travel is closer than we think!

[@apokist]

@@mph650what do you base that on?

[@jimmyclemons3268]

Does time actually exist?

[@rationalmuscle]

conjecture

[@Ryan-pg7uo]

I think given the unfathomable amount of galaxies and solar systems there are, it takes much more of a leap of faith to think life doesn’t exist elsewhere, then it does.

[@robertcox1927]

Awesome stuff

[@faceofdead]

To give you a perspective. Our radio 'bubble' is expanding with the speed of light since the 1900s. Currently, this bubble is about 120 light-years in diameter. This is our coverage. The overall size of the Milky Way galaxy, is about 100,000 to 150,000 light-years....... space-time is so relativistic, it is hard to comprehend from the 'probes' (humans) point of view.

[@LostyMC]

The ignorance of humans. “Just because we haven’t seen it, it’s not there”

[@rebjorn79]

Greetings, Earthlings.

[@kurtkabat203]

Let the force be with you!

[@batchimegdamdindorj8557]

Maybe they’re not there I agree we seem to be the only ones floating along in this universe and yet like siblings we can’t get along ! It’s really sad.

[@thefew.]

What if we are the self-replicating probes?

[@Tom-ol9em]

I liked stopping it after one perspectives then giving my take. Seeing that the other persons view makes wayyyyyy more sense because really crazy forms of life exist where's there's no or little nutrient supplying energy... however life seems to exist even way down where the pressure would squeeze a head to the size of a micron... how can life exist whaaay down there??? Hmmmm 🤔

[@Tom-ol9em]

Oceans are AMAZING I LOVE SEAWORLD. 🐳

[@aussiejournoyeah]

Check out morn 1415 star size comparison 2. Awesome vid

[@Tom-ol9em]

I disagree within 60 seconds.. my guess is we don't even have technology yet available to even detect them? Probably like humas didn't know what a telescope lenses would do?... maybe actually see some Planet's they didn't even know existed until the technology was created to do so... what do you think LEX?? I

[@vivekvicky2595]

exactly. He's so wrong. we as humans haven't even gone beyond solar system yet and he's saying there's no life in the universe lol

[@SiimKoger]

He didn't say that intelligent aliens don't exist. He said that from his perspective it is the most likely scenario. It is likely that out of ten coin flips 5 are heads and 5 are tails. So a scientist would say there are likely going to be 5 heads. You can SAY that all are going to be head but that doesn't mean that you KNEW all are going to be head when it happens. The same way you can SAY that there are aliens out there but you don't really KNOW it, you want to BELIEVE it. Your belief might end up being correct but it has no scientific value.

[@el.blanco8961]

Eh, the James Webb telescope and some new ones that launched recently can detect A LOT

[@MaloPiloto]

I think Sean is spot-on. I have real doubt that there is complex life elsewhere…

[@axlmendez-jt9ud]

I just love how fast they say we wouldve detected them by now, mf we didnt even know the kraken existen until like 30 years ago also the scale of universe and the amount of planets is too huge to comprehend and even if only. 0.000000000000000001% of those planets have life there would still be thousands of them the problem is the distante. Maybe only a selected few managed to crack the secrets pf faster than light travel.

[@AliceP.]

4:35 I can't believe this guy just interpreted 2001 a space odissey's monolith in front of me

[@DarkEmperor2460]

There are *TRILLIONS* of galaxies in the universe and most galaxies have thousands of solar systems... it's extremely probable that there is life on another planet somewhere in the universe. Probably many planets.

[@akaBrilliant26]

Correction BILLIONS of solar systems in each Galaxy…..BILLIONS….the odds of their being in intelligent life on at least one other planet, in universe full of Trillions of galaxies, each with billions of solar systems and billions or trillions of planets is reasonably high….but time and distance might be the primary issue……maybe we all exist a different eras and/or we’re too far from each other to every detect each other…

[@gasstationpeanuts1814]

@@akaBrilliant26 Respectfully, we do not have enough data to assert that. We simply don't know all of the necessary preconditions for life to emerge to say that life must exist elsewhere, let alone that complex life must exist elsewhere. I hope life is common throughout the universe, but we must contend with the possibility that we're alone. Billions and trillions sound like big numbers, but one could begin stacking probabilities such that those numbers become laughably small.

[@MaloPiloto]

Ah, but as Dr. Kipping points out, perhaps the odds against there being intelligent life elsewhere is a septillion to one. That could easily be the case…..

[@jbw6351]

This is such a smooth brain simplistic take. It’s entirely possible the odds for life emerging are infinitesimally small. Even smaller than the number of planets. We could EASILY be alone.

[@Mega-Dinosaurs]

I think people underestimate how vast the distances are...I wager there are a few alien civilizations just outside our solar system even...we arrogantly think we could detect it...I disagree

[@aiya5777]

I think you overestimate the "nothing can travel faster than light" thing that's like the equivalent of an ant living in the ant farm, convinced with "the fact" that there's nothing beyond the ant farm

[@beerman204]

Many years ago who would guess we would develop satellites that could bounce signals back to earth instead of angling off into space? We think we now know what the "deal" is in space travel. That is arrogant.

[@Juingli]

​@@aiya5777This is a possibility 😮..to awe for and its almost significant to realize that Truth lies slightly different from our predictions. There are more peculiar phenomenon to reach out..and maybe that's why we are too basic to answer these..

[@Mega-Dinosaurs]

Let's say there's an alien civilization just beyond pluto which is a vast distance but still close. And their tech was like the 1880s... How would we know they exist exactly

[@Jibuu1]

the way we can detect if another intelligent life form would exist is if that planet exuded elements that normally shouldnt be there. For example, we on Earth radiate massive amounts of radio waves, carbon, helium into our atmosphere but it doesnt occur naturally. That would also happen on other planets too if there was a life form there, the chemical make up would be different than what it would naturally be so we can deduce it has to be an intelligent lifeform causing this change.

[@User-jr7vf]

As someone else said, ASSUMING alien life is like life on Earth, we would detect it by looking at the traces it leaves on the planet.

[@ellomirza]

@@Jibuu1so starting when did we begin to monitor all possible life supporting, as we understand it, planets so that we may notice a difference in their atmosphere and how delayed is the information due to distance? I understand what you’re saying I am unaware of how that’s accomplished and how accurate and realistic it is as a civilization diviner.

[@--Nabe-rius--]

@@ellomirzaThat’s not how that works. We don’t need to actively monitor all planets that may support life and look for changes. We look at the light emitted off of a planet and break down the light spectrum, certain spectrums of light are only created by elements or isotopes that DO NOT OCCUR under any known natural process in physics. Sometimes trace amounts are found and we can explain with a natural phenomenon but ultimately they are looking for light waves that show large amounts of non naturally occurring elements.

[@Jibuu1]

@@jone8626 yeah thats why it said 1890’s technology. If a lifeform is global, then it would be terraforming their planet and be emitting other particles into its atmosphere. Otherwise then we’d have no way of knowing if lesser life forms existed besides going down there

[@mrn8645]

The finite time of life in a vast expanse of time and distance makes pinpointing other advanced forms of life somewhat near impossible. If a probe reaches a solar system tens of thousands of light years away, waits and detects life after 'x' number of years, those who sent it may no longer exist by the time the signal reaches back to them.

[@in_10z]

💯

[@pekkar4460]

Also if life is around other galaxies that argument would hold water even more. Image sending a probe to Andromeda with 10% speed of light. After 25 million years if it happen to find the right star system(lottery) most likely either us or them would be gone befofe we could make any communication.

[@cajones9330]

i just thought that what if part of a the filter is the civilization wasting resources looking for the other civilizations ? why focus out when we should be focusing inward ?

[@kevinshumrick9808]

What if there is plenty of intelligent life out there but they are not technologically capable? Out of the millions of species on earth only one has developed significant technology. It is had to imagine that an elephant, dolphin or octopus would develop technology that would reach the stars. And even if technologically capable what if their ecosystem did not have the equivalent of fossil fuel. We would be chipping stones if not for coal.

[@ruskyexwhyzee9837]

Considering the universe is so extremely vast how could there not be life elsewhere? The problem is these civilizations would likely be millions of light years away and the chances of finding each other would be nearly impossible.

[@jaym8257]

It would be interesting for scientists to run a model as to what we should be hearing now for solar systems on adjacent stars ranging out to fifty light years if civilizations were trying to reach out.

[@JF-yo7vu]

Its vast and there could be life, but not intelligent life. The evolution of intelligent civilizations here on earth prove it. It took 1/3 of the entire universes age, and we are extremely lucky to have emerged. Even with perfect conditions, scientists estimate it would take hundreds of billions or even trillions of years for intelligent life to emerge. So there are less chances of life becoming intelligent than there are of intelligent life existing in a vast universe.

[@jbw6351]

Well you have to consider that the odds of intelligent life coexisting with us in the universe at this exact small slice of time in a billion+ year old universe might ALSO be INFINITESIMALLY small. The odds that life develops might be even rarer than the number of planets in the universe. You have no idea what the probability is of intelligence life developing lol.

[@jaym8257]

@@jbw6351 I really don't disagree with what you've said. It's sobering when astrophysicists indicate how rare life may be in a universe with a gazillion stars and even more planets. And how incredible it was for these elements and molecules to organize into life on this planet. If it happened here, it can happen there. But in that 120 years since radio was developed here, we've not heard a thing in that 120 light year sphere.

[@TDewar]

We are here. Why not others?

[@rayyseason]

I absolutely love this short and great answer.

[@ildiamon]

Maybe we're like the dinosaurs...here for a blip and then gone...

[@Michael75579]

Based on the one example we have, it appears that life arises fairly easily Life that could leave traces in the fossil record arose within a few hundred million years of the Earth's surface cooling enough to allow it to survive, so unless there's something incredibly unusual about the Earth it's likely that life is pretty much everywhere. Given the size of the galaxy, Earth would need to be insanely unusual for it to be the only planet in the galaxy with life, never mind the rest of the observable universe. Of course, life then spent the next 3 billion years as single cells, so perhaps becoming multicellular life is difficult. Or maybe it just takes that long for life to modify the planet to the point that it's suitable for multicellular life; with only a single example we just don't know. A technological civilization took another billion and a half years after that. Finding evidence of unrelated life on Mars, even if it never got beyond the single-celled stage, would allow us to make a small start on putting some real numbers on this. Having said all this, I don't believe we're the only technological civilization in the universe; it's just too huge for even extremely unlikely events not to have happened multiple times. Whether any of them are within communication range, much less the range of physical contact, is another matter.

[@ildiamon]

@@Michael75579 very interesting. What if each of these life forms is always taken out by an asteroid, or solar flare, or climate change, or disease before they ever get to a level where they could communicate/travel the distance, because over billions of years wouldn't some kind of an extinction type event be definitely likely to occur? At least, more likely than a drama free billions of years allowing life to progress to that level. I honestly have no idea, but I just find it odd that if it's so common due to scale we wouldn't have seen one in the area we can observe.

[@Michael75579]

@@ildiamon Possibly, but it seems unlikely that such a disaster would befall every single one of them.We're almost to the point that we could divert an incoming dinosaur killer - see NASA's DART mission. The other things you mention could plausibly bring down civilization if they happened in the near future, but probably wouldn't wipe out humans entirely. You're right that leads to the "Well, where are they then?" question. Maybe they're just really difficult to detect, After all, our bubble of radio emissions around the Earth is only 200 light years across in a 100,000 light year galaxy and isn't likely to persist in its current form for much longer as we move away from large-scale broadcast for radio and television. There's also the question of what stage of technological development they'd be at. Imagine a planet on which life arose at the same time as Earth and developed at roughly the same rate; a difference of only one year in a million would put them 5000 years behind us or 5000 years ahead. The chances of a civilization at a comparable level of development to us within a detectable range are quite small.

[@danielscarbrough4363]

Send a probe and park? Yes, the Black Knight Satellite is the surveillance probe he described!

[@vasiovasio]

I read about this thing for the first time in the '90s and after all these years and every information that I can find - man, it is just space junk, really this is it and it is not an Alien Probe...

[@zacharychristy8928]

It absolutely is not, lol.

[@scroopynooperz9051]

If they're sufficiently advanced, how would we know they aren't here already? Or monitoring us from a distance? We humans have the ability to remotely monitor and study animals without being intrusive, as we want to study their patterns and responses in their natural habitat. An advanced species capable of routinely traversing the vast expanses of interstellar space could have technology we couldn't even comprehend. It is essentially impossible to answer this question without a significant explorative undertaking of the universe, and we just arent there yet. We're basically like the ancient explorers of the old world who wondered about other landmasses and its possible flora and fauna, but simply couldn't know until they'd actually discovered it.

[@tylerjanos2472]

Brilliant 👏

[@jlwilder8436]

Great take, but I'd disagree with the last part. We haven't even sent a human past the moon yet. It takes many months to get an unmanned craft to the nearest planet; we don't even know if the nearest star like ours (the 2 _actually impressive_ stars of the Alpha Centauri ✨ system) has any planets in their orbit yet... so I'd say we are, on that intergalactic scale, nowhere near discoverers of the old world yet; rather, we're more like the scale of humans still marveling at the novelty of fire, just crawling out of the trees, unable to speak a language other than grunts and animal sounds; still sharing the world with the Neanderthals.. - and this, presumably, means (the unknown rapid technological and AI advancements on the horizon notwithstanding) that we may in fact be many, *_many_* generations (many hundreds to hundreds of thousands of years even) away from being on the level that 'those' imagined, type 1 &/or 2 level civilizations out there somewhere, are. So in this way, I agree with Lex: we don't know what we don't know, and of the (I'd agree, probably thousands to millions of) advanced civilizations throughout the universe... they could be right here of they wanted to be 😮 and we wouldn't even know it yet. 🤯

[@SAVAGESUN]

Of course there is intelligent life out there. The universe is immense and the greater cosmos as a whole is beyond our ability to grasp and likely infinite. It may be rare, but it’s there.

[@jaym8257]

But it may have gone extinct one million years ago. There is a time component to all this. And there could be concurrent life but if we could get their signals until they roll by the earth 500 million years from now and we are gone. Anything within the 75 light years that we've understood radio has not communicated with us.

[@SAVAGESUN]

@@jaym8257 Yes, perhaps. My intuition tells me that life exists throughout all course of time since it’s inception and that the cosmos is vast beyond our ability to conceive, even infinite. There is nothing to say that there aren’t an infinite number of universes, perhaps connected by black holes like a porous sponge. Maybe the spark that caused the Big Bang was a collision of universes as they ebb and flow. The idea that the only life at this time is life on Earth seems implausible when given the estimation of 200 billion trillion stars in our universe.

[@anthonyjohnston1618]

@@jaym8257 think about this, if it happened here, why not somewhere else? past or future it's definetly happening elsewhere

[@jaym8257]

@@anthonyjohnston1618 Like I said elsewhere, it would be useful to build a simulation that illustrates this problem and all the variables. For instance, since we've been present as homo sapiens for only 300,000 years and with the ability to use technology (radio waves) for communication for much less, we might have missed a signal that came by one million years ago. But if there are large numbers of potential long lived civilizations we should be hearing something by now. We haven't.

[@rationalmuscle]

@@jaym8257 I think the equally interesting question is "HAS" it been there? If it has, chances are it is.

[@christopherviers8302]

Or maybe... just maybe... the fact that the vast universe is larger than is comprehensible, so the unfathomable distances that exist between different life forms will never allow us to encounter each other...?

[@ttrev007]

how would intelligent life be noticeable? we only recently have the ability to calculate that planets exist out side our solar system. We just don't really have great ways of finding alien life.

[@gianttwinkie]

The question about aliens never seems to talk about time. So over the life of the Universe, has there been alien life? Likely. Is there alien life out there now? A lot less likely.

[@mmann5914]

How good was Red Dwarf?

[@kawataufik5098]

Everywhere but leaders not tell or not try to find them we blind because our leaders not love us

[@arthurwieczorek4894]

'Life figures it out.' That's evolution. That's DNA conserving itself in its dysteleological way.

[@user-xu4fz3go9f]

Given the size of the universe and how far away everything is there has to be life out there. It’s just too far away.

[@T.Durden666]

of course we are not alone the universe is just too big

[@ranaskip]

Would the Universe even exist if we were not around to know it does? Perhaps the Universe created us so that it could be aware of itself.

[@chucky8819]

It seems like life finds a way! That’s a very unique and smart thing to say

[@dahveed72]

Not unique. Jeff Goldblum said it in this fantasy movie about cloned dinosaur.

[@johnskujins8870]

There could also be lots of planets with complex life like it was for the dinosaur age here on Earth for hundreds of millions of years. Just no radio technology.

[@Jm-wt1fs]

Life “finds a way” to evolve once it already exists and has the tools for evolution. It most likely does NOT just “find a way” to form spontaneously, it probably requires very specific circumstances and is incredibly fragile at first at high risk of quickly going extinct, like a flash in the pan It could require circumstances so specific that the probability of complex intelligent life evolving is absolutely minuscule, near-zero. We don’t know, but absolutely everything we have seen so far has indicated that it’s just not there. That said, we can only see exoplanets as tiny dim specs on stars so we can’t make any conclusions yet at all

[@mrn8645]

A million to one chance will still become a large number when dealing with trillions and trillions.

[@Jm-wt1fs]

@@mrn8645 sure but the chance could be something like 10^-10 (which would make us probably the only life in the galaxy), or even 10^-50 (which would make us the only life to ever have existed in the visible universe) We don’t have any upper or lower bounds on the probability of life forming spontaneously other than the one data point that tells us it is actually possible haha. But as big as the universe is, life could be so improbable that it never happens, not to mention multicellular, intelligent and social life which surely is orders of magnitude more unlikely

[@mrn8645]

@@Jm-wt1fs - with the sheer number of galaxies, even only one form of life in each galaxy would produce a large number. It's all just ''probability''. However, the probability of there being only one seems less likely than there being a higher number. The reason being, there are a finite number of elements and ways in which they can exist. So with each throw of the dice so to speak, the chance of something repeating would increase.

[@Jm-wt1fs]

@@mrn8645 we have no idea how many “sides” the dice have. Life formation could potentially require 50 individual things to happen in the exact right order or else it won’t multiply. The probability of these things happening in the exact order needed would follow a factorial distribution 50! (Magnitude on the order of 10^64). That is almost 3x all the stars in all the galaxies in the entire visible universe, which people estimate to be around 10^24. So despite the massive universe size, the odds could easily be even larger. We just don’t know

[@mrn8645]

@@Jm-wt1fs - we know how many elements there are. We also know that life at least only needs ''sunlight, water, air, habitat, and food''. The majority of those 'individual things happening in the exact right order' have already happened, and we can observe them. Such as sunlight and habitat - a planet orbiting a star. Also, counting the number of visible stars doesn't take into account how many planets may be orbiting each one.

[@holgerjrgensen2166]

Life is Eternal, the Only existing Reality, No one have seen the Being, behind the Living. There is Only the same Eternal Life, We all Refer to it all the time, I, I, I, I, I'd, I've, there is Only the same I. One of the main-reasons why We don't see it, is because We all have our very own Eternal Consciousness. So, We all See Life in our own Perspective, and Not used to see behind the Stuff-side. (the 'Opposite Perspective') But the Eternal Life is Alone, there is Only the Eternal Life, The Eternal Life have No Neighbour. We all know the quality of being alone, and be together. So the Life-Unit-Principle makes Life full of Life, all Life-Unit's have in principle the Same Size, Life-Unit-Size, and the Rainbow is their naked Signature. So, Quantum-confusion, time-dialation, and Stuff-side blindness, does Not explain the Life-side of Life. Well, there is NO aliens, Only Life-Unit's.

[@AdamLeis]

Lex glosses over the *very* difficult part: biogenesis. The *start* of life is stupid difficult. Wtf does it even mean for chemistry to "self organize" into life? dafuq?

[@tahirturdaliev8518]

If I’ve met the aliens, I would dance

[@BillAwty]

If an alien civilisation was more than 200 light years from the Earth what would they see if they looked in our direction?

[@Jjjjjjgggg]

goatse.jpg

[@WeAreLegion-]

No

[@Hysteresis11]

Yes. Complex intelligent life is a fluke; a flash in the pan.

[@jimmyzhao2673]

Brandon, at the car race, the crowd chanting.

[@BlastinRope]

darmok and jalad, at tanagra.

[@ckml6648ify]

If there are no aliens, then human beings are just like fish in an aquarium, someone put us here.

[@addis11100]

Alone of what noromoroen

[@ichevtchenko]

Play pyramid song by Radio Head while watching this. Trust me.

[@franciscogarcia-yw7fd]

It is a calculation. Calculate the probability of all conditions of life to have met. Lets say it is 0. (A million zeroes)0001% And now calculate the number of planets, rocks, moons and asteroids, not only in the observable universe but in the whole universe. You come up with the only reasonable conclusion that there must be life outside Earth. The number of planets, rocks and moons exceeds by a huge far, the probability of life conditions to have met.

[@xEp1cxSPorTZ]

Francisco your calculation is wrong. 1 in 10^million vs 10^24 are vastly different numbers. There are 100 billions stars in a galaxy and 2 trillion galaxies in our universe. Using your numbers it would be almost certain no life would or has ever existed which we know to not be true

[@franciscogarcia-yw7fd]

@@xEp1cxSPorTZ that is why i use lets say". It is a conceptual example. The rationale is valid tho.

[@ericsonamaral7895]

Imagine there is an intelligent civilization, but at the tech development level as the Romans, the Greeks, the Assirians, etc. Would we be able to identify their existence from here on Earth?

[@pongtswaila7922]

JWST can see galaxies near big bang, but can't find a credible hint of civilization elsewhere.

[@ValidatingUsername]

Day n+1 of trying to correct science communicators interpretation of Penrose diagrams 😂

[@rayyseason]

It’s really funny how the people in the comments section seem to be actually more reasonable, intelligible and understanding than these hosts.

[@oevereng]

We are not watching space in realtime are we ? We are watching light that's travelled hundreds of thousands of years if not millions or billions, modern human civilization is less than 200 years.

[@Ravenseyes10]

It makes sense to me that we couldn’t see anyone out there… Alpha Centauri is our closest neighbor. 4 light years from Earth. The photons reaching our eyes are 4 years old?… it could have blown up 2 years ago but we wouldn’t know for another 2 years? No matter what magnification we set our telescopes to.. with our current technology. Unless they fly within range we won’t see them. And, I doubt their spacecraft have big headlights in front of them like a car or a choo choo train. I’m sure they would use other sensors to see what’s around them. My gut says yes there is life out there.. lots of it… but, like us, they are wondering if there is. The only way we will know for certain is to start hopscotching across the universe. Maybe we’ll meet somewhere in the middle.. This is a point I rarely hear when people discuss aliens and life on other planets, yet, I remember learning this in public school as a kid… on a rare day that I payed attention..

[@nuntana2]

The Centauri system is a bit over 4 light years dude, not 4000. Regards observing them, you don't see directly, more through spectrographic analysis of a system's star, with either abnormal dimming due to Dyson Spheres or telltale markers in accompanying planets' atmosphere which suggests life. This we can already do.

[@guitarriff123]

@@nuntana2 Precisely. The fact that we haven't seen any signs of microbial life yet isn't promising. You'd expect that if microbial life exists elsewhere, it'd be everywhere.

[@Peter_Trevor]

You should’ve paid more attention at school, and now spend less time making false statements on KZbin. 4300 light years!

[@Ravenseyes10]

@@nuntana2 My bad on the math… I saw a comma.. haha! But, a Dyson sphere? Dude, how close se are WE to accomplishing that.. that is only a concept.. oh, the resources that would take.. and it’s a concept created by us. And yet we are floating in space and landing on the moon and sending probes everywhere. Who’s to say life elsewhere isn’t in the same spot with their technology and swimming in the shallow end of the pool like us? They may be looking at the photons from our planet back before we had our moon. Which brings me back to what we see when we observe a planet with our telescopes… is it not true that the further a planet is the longer it takes for photons to reach our eyes? If the sun went out suddenly, would go out at the same time for everyone or would it take a certain amount of time for us on Earth to know? I appreciate the correction on the mathematical error, but there’s no need to be pedantic. I certainly wasn’t trying to be.. it was just a simple observation… from a simple mind.. cheers!

[@Ravenseyes10]

@@Peter_Trevor Don’t get your pen holder in a bunch, buddy! I corrected the math. Thanks for pointing that out so kindly. We all can’t be as SMRT as you! But, my point (which you missed) still stands… have a groovy whatever

[@joaquieroux]

perhaps the aliens have decoupled from conventional reproduction and can reproduce through these self replicating probes. Scary

[@jaym8257]

All the astrophysicists are biasing me to the camp that there is no other life out there. I don't know what to think about that.

[@a552bcx]

it takes 23 minute for a person on mars to receive my email if i sent it now. radio communication is finite

[@justmythoughts2786]

It takes a whole lot longer than 23 mins bud

[@justmythoughts2786]

Because it’s gonna take longer than 23 mins for someone to get a server and a cpu there for them to even receive it

[@PlatinumState]

Thats a big claim to make that there are no other civilizations out there. The universe is so huge that we may never know

[@JonathanTBE]

The argument makes no sense, why just assume that intellegent life would inevitably populate the entire universe and go as far as possible as fast as possible? We have no means to assume that, yhere can be billions of civilizations like us or more primitive,more advance, or just completely different, and we are just too far apart to even know.

[@Insignia6]

Once you see how vast the observable universe is, it's a no brainer that life exists outside of our planet.

[@aussiejournoyeah]

Fermi paradox

[@Norm_MacLeod]

If an alien civilization was indeed advanced enough to come to our primitive planet, why would they? Other than to have a good laugh.

[@mikasasukasa4479]

"The Universe is under no obligation to make sense to us" which is why I think any argument or theory for aliens is moot. I think we are alone.

[@ellomirza]

No way the point of all this impossibly to comprehend vast gigantic space and matter is to support some life on one tiny part of it. Whatever life happens to be it is just a part of this thing like black holes are or stars.

[@harpreetnijjar5585]

Guru Granth Sahib!!

[@johnpinckney7269]

Lex has never looked at the enormous problems of abiogenesis. The probability of DNA and a cell forming from any precursor soup is much much less than 10 billion monkeys typing out all the books in the British Museum. God has left his signature my friends.

[@christoforos4126]

Interesting how they can shoot the shit about unprovable things they "believe" about alien civilizations. And yet so many (and perhaps this isn't relevant to either of these fellas) people will become belligerently irate over someone talking about their belief in God. The human mind is fascinating and hilarious.

[@jaz4742]

The fact that you think aliens and god are the same kind of "made up thing" is why youre religious.

[@maxwell8758]

Because we know aliens are physically possible. Life on earth exists, so we know it’s possible. Gods however are a straight up delusion.

[@scroopynooperz9051]

What if god is just one of them aliens that dropped goo in the water of our early monkey ancestors? What if god has his own god, and he's wondering the same thing about his origin story 😂

[@danielscarbrough4363]

Nutters will do nutter things....extreme nutters for their fave sky gawd and there are nutters for "the science"....extremists all around. LEX ain't nutters...he's thoughtful, open and fair with everyone regardless of beliefs.

[@jimbob8992]

1:32 Surely, it's when people start claiming to know the mind of this ' God' and how you, me, and everyone else should act in their day to day life? Also, I don't think the concept of there being other biological life in the universe is a massive leap in what we already understand about nature.

[@AB-tn3jd]

Even if ONE intelligently advanced civilization existed in every galaxy, on average, you are talking about trillions of said civilizations. The problem arises in of course communicating with them, which is likely impossible until one or more civilizations develops some wormhole techonolgy (if it even is possible? hence, again, if it is not possible, it lends credence to a reason why we see nothing else out there in our own galaxy). Maybe even the average is 0.5, but you're still talking about hundreds of billions of civilizations. If I were to guess right now, because we KNOW life has found itself on Earth, and did take time to eventually make humans, and therefore given the numbers and size of everything else should occur elsewhere, I'd say there's a decent amount of LIFE, but not many intelligent civilizations in a galaxy given the timeframes involved.

[@bobobrien8968]

On a much less intelligent tangent; does Sean not sound a lot like Don Felder ex Eagles guitarist?

[@rayyseason]

How arrogant and naive it is to assume that there is no one else expect earthlings in the universe.

[@BridgesOnBikes]

I’m guessing if the aliens don’t want to be seen then they won’t Sean.

[@toddsmith5715]

But the point he was making was accounting for the supposedly massive number of them over the vast expanse of time. Supposedly, there are millions, but they could not all have developed at the same time, and they could not all be at the same level of development. Some would be advanced enough to conceal themselves from us, but others at different stages of development would not be. We therefore should have been able to detect SOME of them by now, but so far, after well over a half century of peering out there, we've seen zilch. Where are all the megastructures? Some of that would be left behind by the more advanced and would still be in use by at least SOME of the less advanced. Yet we see absolutely nothing. I'm not one hundred percent convinced there is no life out there, but this was the point he was trying to make.

[@guitarriff123]

I love Lex, but the constant repetition of "I believe they are everywhere and we just can't see them", is very dogmatic and hard to get on board with.

[@cengiztaner4754]

Lex is not an extremely bright person.

[@andreasleonhard1512]

@@cengiztaner4754 That is absolutely relative lol. He's far brighter than most people.

[@ImCalledWoods]

There are lots of powers at play that we cannot tangibly see. But they exist.

[@LBTennis]

You could combine the biomass of plants and animals together and you still wouldn't equal the biomass of Microbial love on this planet. Most of the life on this planet you can't see with your own eyes. Open your mind

[@guitarriff123]

​@@LBTennis We do see microbial life all the time though...

[@Medieval_Toad]

I cant take anyone who gives a confident answer to this question seriously, no matter their level of education or position in society. To insinuate that you know anything about this topic is to insinuate that your intelligence outweighs the vast mystery of the universe and life itself, and I don't think thats the case.

[@rsj3039]

We cannot even communicate with Dogs, Whales, Eagles, Ants etc...I so disagree with Prof. Carroll

[@dahveed72]

Humans communicate with dogs, cetaceans, and birds all the time. Wtf are you talking about?

[@rsj3039]

@@dahveed72 oh really, please tell me what they think about killer whales eating dolphins, or why don't chicken revolt? I missed that 🤔😂

[@Vlad-the-Inhaler]

Dogs, WHales, Eagles, and Ants also can't travel through space. It's reasonable to believe that any highly intelligent life that is able to cross solar systems (or galaxies) would be able to solve linguistics.

[@PaulAdkins-ex3cg]

What if they have always been here under the. Oceans an ground in valcanos an were ever else they want to be an we are a infearer species to them an dont want to iner act with us cause we are not in the same realm tec wise like a new born baby not to mention violence oreanted an chose to just give us a blink of a eye for the hell of it every now an then cause they dont find us to have any seance

[@l_combo]

Dark forest hypothesis

[@julythrunov]

please atop faking humility Lex. You’re constantly dumping buckets of humility on everyone you talk to. We get it. You’re humble. Enough. “I’m afraid we won’t recognize the intelligence in it” what, really?’ are you really afraid of that? At one point, Sean calls him out on it, at about 8:15 on the clock, Stop the posing Lex.

[@EricMalette]

It's a pretty scary thought when a guy is this smart can't envision a universe with intelligent life aside from us. Not that I have anything against him I just think it's it's scary because he knows a lot more than we do.

[@phillipbarr]

Its ignorant if anything, to think that we are the scale of intelligence in the universe. We can only reference ourselves. Theres definitely life out there that is advanced.

[@enginekun]

For the Santi civilization, it took them an awful long time, haha

[@apollonia6656]

So: UFOs (if such exist) could actually be AI Probes ?😂 Why cross galaxies to visit Earth and not make contact.....whether via Wormholes or by some still unknown means of travel.....then wait for an answer: " Ah, that planet (Earth) has what appears to be intelligent life, what do we do next .....not more proves surely !

[@gsp3428]

We are not alone in the universe, God is there with us.

[@ninobrown9564]

We are the universe. The aliens are inside us. They are small and everywhere around us. You can pick em up with your canera

[@toddsmith5715]

You need to get off the shrooms.

[@dnizzle18]

Drake equation says no

[@hajsh67]

I respect the curiosity and the genuine questions from Lex, but not the part where he (on purpose or not) puts words in Sean Carroll's mouth in some of his responses, which don't reflect what he actually said. This is the reason why I only tune in once in a long while when there is an interviewee that I care to hear from. edit: I don't think it's disingenuous when Lex does that but he should learn to listen a little better to what is being said rather than trying to make it fit into whatever picture he has in his head.

[@Zeroxo1]

Is society ready for intelligent aliens

[@URKNIGHTMARE69]

disappointed in Sean responses. my thoughts from this viewing is this, Sean if there can be multitudes of universes then there are multitudes of life forms. should we be all there is , probability is false and by all means we live in a simulation

[@justmythoughts2786]

The real question is , is if e=mc2 does mc2=e

[@virdi1992]

Am I narrow-minded to think this guy is narrow-minded?

[@alexduran2881]

First 2,000 gang

[@veganfit2388]

Some of your guest are so ignorant. Why are you putting ppl on your podcast whom aren’t even aware of the reality that extraterrestrials are real.

[@michaeldodd3563]

First!

[@alexduran2881]

First 17 comments like this only

[@madman3826]

Octopuses are aliens 😊.

[@vonbleak101]

No... No we are not... :)

[@hakiza-technologyltd.8198]

scientist don’t believe «they find out »... hahahahaha... until now « we are alone ».

[@91wheelz]

"what if it typically takes 100 billion years?" sir, the universe isn't even that old..

[@Achiements]

He’s saying we could of came incredibly early and is unlikely to find life.

[@91wheelz]

@@Achiementsgot it! I didn’t correctly interpret what he said. I wonder though what the odds would be of another civilization “finding a way” from microbes to intelligent life earlier than say 100 billion years; surely there would have to be a number above absolute zero and who knows, maybe that civilization came and went or is hidden somewhere and we just haven’t detected them yet

[@fullmatthew]

Lex quoting Jurassic Park and thinking he's original 😂

[@cropredator1027]

Seann caroll talking nonesense

[@mikefp3]

Life finds a way, except there are more extinct species than living.

[@djjefferson4200]

Observe the Earth. It seems that humans are the “aliens”. 😉