The Fermi Paradox: Absent Megastructures

[@specialagentdustyponcho1065]

The more I learn about the fermi paradox the more I'm convinced the solution is that we must be among the first in our observable space and there's something preventing time travel. We can't see any megastructures because they haven't been built yet. We are babies in a world of babies, and nobody's stacked their blocks high enough to see.

[@Evil0tto]

Or we can't see megastructures because there's nobody building them, because there's no need. If you have a source of energy that we don't know about (or even speculate about yet) that can power your civilization then why build a Dyson anything? Why colonize the entire galaxy? Saying that we're the first, or that we're alone smacks of "Earth is the center of the universe" long-abandoned science.

[@specialagentdustyponcho1065]

@@Evil0tto If there's some kind of energy source that gives more power than a dyson swarm for less effort, the owners would be doing a lot of things with it, which we'd be able to see.

[@JM-zg2jg]

Nah. Dark matter. They say 90% of the universe is missing. It isn’t missing, it’s just covered up with alien mega structures.

[@jamesfowley4114]

@@JM-zg2jg we would see the waste heat, unless it isn't here yet.

[@KingOpenReview]

@@jamesfowley4114 Could we observe the gravity before the heat?

[@Agreatdayneverends]

Decades from now Isaac will be viewed as a legendary youtuber....the quality and volume of his work is mind blowing...

[@alisvariety9657]

*still be viewed as

[@FitzgeraldStanburyWeissV]

He's already legendary.

[@GodWorksOut]

It has already been a decade since I started watching

[@JohnSmith-lh3ht]

As someone who recently watched it, I salute you for being able to sit through Moonfall and manage to not fit a single complaint about it into the episode. That's strength right there.

[@isaacarthurSFIA]

It took some restraint John :)

[@victoralexandervinkenes9193]

@@isaacarthurSFIA lol

[@fg4hg594]

I literally watched moonfall yesterday and I can confirm, that's one willpower right there.

[@prolamer7]

@@isaacarthurSFIA Megastructure is one big red target saying "here is real threat to you all out there". Only sensible approach is to not built such self destructive beacon or to shield in very advanced ways.

[@vincent_hall]

@@prolamer7 Sensible if you're concerned that others will advance beyond you. Maybe sensible, yes.

[@code4chaosmobile]

I like the plot of "pushing ice" where life was just rare enough throughout the universe to not overlap, so some really ancient aliens build a device to get everyone together but waaaay in the future

[@Mofi357]

@Darryl Revok Murder in the dark

[@colinsmith1495]

I remember a Cool Worlds episode that looked into not only how likely life might be to form, but also how starts move through the galaxy and how long an interstellar civilization might last. Playing with the variables, there were LOTS of options where life popped up rather frequently, but either died off or just 'drifted away' too quickly for any potential contact without FTL. A lot of assumptions went into that, since we know so little about the variables in question, but still a fascinating listen.

[@Mofi357]

and with that thats all this channel is Regurgitation im out

[@colinsmith1495]

@@Mofi357 If that's what you really think this channel is, you aren't paying much attention.

[@code4chaosmobile]

@@abhiprakash74999 do'h, i should have been thinking. sorry :(

[@littlegravitas9898]

Never find me absent on a SFIA Thursday release

[@DanielGenis5000]

Lots of books about finding ancient celestial artifacts, but none of them that great. Listening to Isaac is more interesting than some of the space opera plods….

[@yahnmahn9035]

To Sleep In A Sea of Stars by Neil Gaiman is pretty good

[@shawnjohnson9763]

Instead of Clarktech, what if we're a product of Ricktech and our universe was created to power someone's car?

[@paulmadden5986]

Non stop incredibly tantalizing information, inter-dimensional journeys for the mind. I can't get enough of this Isaac and team, thanks for providing frequent and updated content. I listen to all of your work several times. 💙

[@camwyn256]

I didn't know he had a team. Wait... Does he have a team?

[@camwyn256]

Oh. There it is in the description. Still it's all written by Issac, 4 editors and a bunch of graphical artists

[@georgemorrison458]

Faster than light travel is impossible and breaks causality. You can travel somewhere like andromeda in only 15 years without going at the speed of light just going at 99.99999999% the speed of light the only problem is time dilation takes place so in your space ship 15 years goes by but on earth 25 million years goes by. Because of how spacetime works time travel is impossible. And if you were travelling at the speed required under the speed of light before even reaching 80% of light speed the radiation would be hitting you at such a speed that it would damage your DNA and would blow up your ship. Thus faster than light travel is impossible l.

[@AltimeterAlligator]

I wonder how many distant galaxies we observe at low resolution are unintentionally camouflaged, because some oddball civilization prefers to build galaxy-shaped megastructures. If we ever meet these dudes they'll say, "What? You build stuff that _doesn't_ resemble your surroundings? Unfathomable."

[@RobertBlair]

Suppose 99.99% of galactic size civs do camouflage their impact on their galaxy. That leaves 1 out of 10,000. Out of the billions of galaxies out there, there would be a few with egos large enough to dramatically alter their galaxy's electromagnetic signature, so it could be visible a billion light years away. So if such civs are possible, we should be able to see them, if we look in the right way.

[@josephjucker5620]

When you reach the galactic scale it would be extremely inefficient to shape a structure as anything other than the natural configuration matter takes

[@smileyp4535]

@@josephjucker5620 "if brute force isn't solving it you're not useing enough"

[@josephjucker5620]

@@smileyp4535 If you enough available energy to mold galaxy size objects for fun there's a good chance you won't need to exist in a reality where it matters. I won't deny the possibility of contrarian super beings just trying to make us mortals scratch our heads for S&Gs

[@grumpymonk2460]

@@smileyp4535 spoken like a true member of the Emporium HAIL THE GOD EMPEROR

[@shoujahatsumetsu]

I love the new video smell when you get it straight out of the box

[@colinsmith1495]

I would love to see a realistic breakdown of the timeline in this supposed Fermi Paradox, and I've only done bits of it myself. Fermi said the universe was ancient, why aren't there aliens (VERY abridged)? But, for life to form, how 'ancient' is our universe really? What I mean is, for a 13.8 billion year old universe, how much of that timeframe could we feasibly expect life as we know it to form? Could there be aliens 13 billion years ago? VERY unlikely. From what I understand, it's unlikely that there were even rocky planets at all back then, much less carbon-rich planets with tons of heavy metals. But, really, how long does that actually take? How long did it take for the first stars that produced the REALLY heavy elements (Uranium and the like) to go super-nova and distribute those elements? Heck, I think Uranium may have needed neutron star collisions, right? How long did it take for that debris to form into planets around a new, younger start? Now, the other question, how common were those back then? Let's not assume that a planet with the right mix of elements formed in the Goldilox zone in one of the first 3 stars that it could have, and that life then formed on that first planet it was possible on. Let's assume there's some odds here, so odds go up as 'heavy metal rocky planets' become more common. Now what about star type? We orbit a relatively calm, large, warm star. Are those more common now than 8 billion years ago? Ultimately, my question is, should we be asking 'where are all the aliens in such an ancient universe' at all, but rather 'how'd we get here so early' or 'yeah, looks about right'? I've watched most of your episodes, but I don't recall one like this. Have you done one?

[@dibbidydoo4318]

isn't that question part of his Fermi Paradox: Firstborn?

[@nicholascarter9158]

So we sort stars that still exist into two populations. Population 2 starts are the older ones. They contain between 10% and 1% as much non-Hydrogen, Non-Helium matter as Sol. Which suggests that their planets contain a similar fraction of those elements. But then in turn, this matter isn't equally distributed between the elements: it is very unlikely that any planet circling a Pop2 star would have enough of any element heavier than Fe to form an industrially meaningful deposit. These planets won't have Uranium, Gold, or Copper in enough abundance to support a planetary supply network. The younger Pop1 stars makeup about 2% of all stars in the Milky Way and they are younger in the sense that they are about 10 billion years old instead of 12 billion. To put it another way. There are about 2000 Sol- like stars that have rocky planets within an earth like habitable zone that are within 100 light years of Sol, working out to one possibly Earth like planet every 13 lightyears on average.

[@cosmictreason2242]

Those heavy elements are still there in the oldest stars. The conventional cosmology is wrong. Reject deep time, embrace YEC

[@nicholascarter9158]

@@cosmictreason2242 We aren't cowards in these parts

[@Lusa_Iceheart]

@@nicholascarter9158 Bit of an addendum to those numbers. Yes the Milky Way is about 2% Pop 2 stars, but just under half of all stars are Red Dwarfs (M-type)which are dubious at best as whether they could develop life. Great for an already technological civ to come in an colonize, but horrid for life to develop around. Red Dwarfs are highly likely to have volatile solar winds, and basically just strip atmospheres off planets (which would orbit closer than Mercury since it's a much smaller, cooler star) and there's a high likely-hood of tidal locking planets too, which is a nasty complication. Sure, there will be rare Red Dwarfs that are atypically calm and their planets might retain atmospheres, but these would be so rare that they'd be swallowed by your margin of error. Other end of nasty stars are your A, B and O-types. Way too short lived to meaningfully produce life, barely enough for planets to form in the longest cases let alone develop intelligent life. One step up from an M-type is the K-type, which are probably good candidates due to their stability and long lives but their fairly rare (12% of stars). Our star, Sol, is a G-type and even rarer (7.5%) and Sol in particular is a very calm G-type. F-types make up that last group, live long enough that they could develop intelligent life (in theory) and aren't unrealistically brutal like the A, B and Os but are very rare (3%). So really we're looking for intelligent life developing around Ks, Gs and Fs and they'd have to meet high criteria when it comes to solar wind stability, flare rates, flare intensity, and have a docile neighborhood (no supernova neighbors). Oh, and there has to be coincidentally a rocky planet in the goldilocks zone with liquid water. A binary star system (which most stars are bound in) greatly complicates the ability to form a goldilocks zone. So, yes, roughly 2% of all stars are Pop 2 and should have material for rocky planets, but that's just one box of an entire laundry list of boxes that MUST bet checked to develop life on a planet, let alone get that life to intelligence. Even then, if life gets to intelligence it might be stuck on a super-earth (which seem to be super common despite the Solar system not having one) where gravity is too damn high to reasonably escape with anything short of a fusion candle drive, and if we were stuck on such a rock we'd probably given up with ever trying to get into space. Imagine if it took all the effort of the entire Apollo program to put a single cube sat in orbit, just how quickly we as a civilization we give up on the notion of escaping the bounds of one planet. We DID give up interest after the Apollo program to a great degree. Such a species might be more prone to use the nuclear option that we thankfully backed away from. Or they might end up going the digital route and turning 'inwards to go outwards' as it were with virtual worlds. Either way, they're not building megastructures. There is a LOT of hurdles that need to be cleared, so many of these 'Great Filters' that when you apply them all with even a guesstimate of what the pass/fail threshold is, you get roughly one in a super cluster of galaxies. *looks around* Hmm, we might be that one. See the "Firstborn" and the "Great Filters" Fermi Paradox videos.

[@hamentaschen]

Fermi... My favorite of the Paradoxes! Thank you I.A. and Happy Arthursday everyone!!!

[@Bob-lr2xp]

I'd like to see Isaac do an episode about Planck Energy, and how a civilization could use it to literally rewrite physics.

[@mba321]

Seconded

[@godamid4889]

It's just a unit of energy?

[@mouseblackcat5263]

It would be nice if we could first establish if Physics is even Consistent across Space/Time. We have had to fill in the blanks with things like "Dark Matter" and "Dark Energy" because we really dont know what goes on outside our Solar System, or even at the extreme reaches of our System. O.o

[@godamid4889]

@@mouseblackcat5263 that's not the problem you think it is. We can establish physics is consistent outside of the solar system. Dark energy is not some unsolved mystery. Dark matter is like any field of science - we discover it's existence and then figure out what it is. Business as usual.

[@blackoak4978]

To sum it up perhaps snidely and obliquely, what we think about dark matter is clearly wrong, and what we think about dark energy isn't even wrong. We may find that we have to develop AI to understand the actual laws of physics, only to find that we do not understand, or are incapable of understanding, what the AI discover. We are bags of biological matter who's prime 'design' parameters are to consume and reproduce. Nothing in that requires us to be capable of understanding the core of a black hole, or the building blocks of space-time

[@tamasmihaly1]

Neil Tyson and Michio Kaku love to talk endlessly about how insignificant we are and that aliens wouldn't care to interact with such primitive creatures. I always felt like this is more a reflection of their own emotional minds than a result of critical thinking. Everyone seems to love those two so much, but personally, I think they love the camera more than anything. I much prefer the realistic approach Isaac takes. Intelligence without curiosity would be sad and boring.

[@cosmictreason2242]

I think you can make an argument that intelligence necessarily implies interest regardless of curiosity, if you consider God, theologically. He knows everything so he has no curiosity, and yet he’s still intimately involved in everything humans do. Follow me here. It means if you have unlimited access to power, your involvement with everything in existence will also be unlimited

[@mouseblackcat5263]

Yeah, its rather sad that time has proven what Terrible Human Beings people I used to respect, such as Bill Nye, Degrass Tyson, etc are. :(

[@mouseblackcat5263]

@@cosmictreason2242 Im pretty sure God/Creator/Universe had no Charitable Intentions in creating Humanity, all the Evidence points to us being no more or less than a form of Entertainment. A DayDream of the Cosmos. O.o

[@cosmictreason2242]

@@mouseblackcat5263 that doesn’t really work on closer inspection. If you find yourself wanting to explore the subject, Answers in Genesis is the place to go

[@DistinctiveBlend]

@@cosmictreason2242 Just no, your dusty old tomes have nothing of value to say when it comes to the universe.

[@jefferywise1906]

It’s interesting that in almost all SciFi movies and TV shows all empires are essentially K1 civilization with FTL capabilities. All there colonies are same just planet civilizations on K1 levels at most. Yes a dead Dyson Sphere was found in STNG but that’s about it. Hollywood is stuck in a limited 1960’s view of the possible.

[@AndrewManook]

The HALO series with the forerunners does a good job of this.

[@cosmictreason2242]

@@AndrewManook please don’t say you mean the paramount series

[@cowmoo5596]

@@AndrewManook The Forerunners achieved a level of technological prowess I have yet to see in any other series, I don’t get how other franchises lack anything even close to the Forerunners, they completely wipe the floor with practically any other alien civilization in media

[@KarlRosner]

15:30 Aliens can go the exact opposite way with regards to 'being careful and acting hostile to new things' the puppeteers from Ringworld were that way, they were HYPER cautious and kind of terrible because of that mentality. In fact they praised other people for being cautious in the same way we would praise some one for being kind.

[@nosarcasm1]

One main thing about discussing the fermi paradox, which borders me, is the time scale. When we look outside into the Universe, than we are looking into the past. So, from our state of view, the chances for other species must drop naturally, when we look further (farer??) away. We looking in a past, where the variation of elements are lower. First, heavier elements need to produced in dying stars or in other processes. Than there have to form new solar systems with this heavier elements. I don't know, what's a valuable time its need to form. Our system is round about 4.5 billion years old. An Alien- civilization that's, one million year old, isn't observable, when it's 10 million light-years away. We need 9 millions more years to observ them. Is it a bit clearer what I want to say?

[@Mr.Nichan]

He kind of mentioned this, though he didn't explicitly mention the elements thing, just the idea that life may be more likely to arise later in the universe. I know he knows that one of the most popular explanations for that is the lower metallicity of the past universe, though. However, he also noted that spherical shells of the universe further away have larger volumes. (He actually said that spheres have volumes proportional to the cube of the radius, but you can also say that spherical shells have volumes approximately proportional to the square of the distance.) That doesn't necessarily, or even likely, cancel out the effect of earlier stages of the universe being less likely to have life, but it does provide at least a partial cancellation, and, obviously*, goes beyond cancelling once you get close enough to us. *It's obvious because, obviously, a sphere of stars 500 light-years from Earth is more likely to contain aliens than just the rest of our Solar System, and our whole local group is even more likely.

[@wobogoat3379]

Yes. But you could expect advanced civilizations in the milky-way. That means that you should see all civilizations older than 100.000 years. That's not much of time.

[@EnPriBri]

One thing I always like to point out in Fermi discussions is the in-built assumption that intelligent life might use chemical or electric power, rocketry, and extrasolar travel. A lot of our steps along that ladder were rather precarious and for most of our history unthinkable. Given that it took eons for us to do those things and we need to use the remnants of eons of dead things on our own planet to get them running (and we're close to using them up after only a few centuries), I think we often take for granted that techs to get to space, find much use in it, and be able to do things with it are immensely huge filters in and of themselves.

[@sa.8208]

this... nigga i thought we'd have flying cars and be able to go the moon by now i also treated my body like complete shit in trust of medical science lol internet

[@leepreston9637]

We are no where close to using up all of the fossil fuels.

[@maxkronader5225]

There serms to be alot of overlap between Fermi paradox discussions and filter discussions. The Fermi paradox, at its core, simply asks that given the size and age of the universe, why do we see no signs of advanced alien civilizations? In my opinion, that question has been answered definitively. We find no observable alien civilizations because there are none within our range of observation, period. That solution in no way implies there is no life (or even intelligent life) out there, just that there's none that have created a detectable civilization. There could be a stone age hunter-gatherer equivalent intelligent species every 100 light years, for as far as we can see in every direction, but they wouldn't be detectable with current technology. The question of why they never created a civilization that can he detected is, to me, a separate question from the Fermi paradox.

[@leepreston9637]

@@maxkronader5225 it took modern humans (that is excluding all of the other more primitive hominids) at least 200,000 years to figure out agriculture. This hints that such a development is not guaranteed.

[@maxkronader5225]

@@leepreston9637 Correct. If we were to reserve petroleum for lubricants and internal combustion engines and generate electricity with nuclear, renewables, coal, and natural gas, we could continue for centuries before depleting fossil fuels.

[@Votrae]

It wasn't the major point of this awesome episode, but your points about rationale and humans was really refreshing. Self deprecation is standard fare in the human narrative, and we almost certainly deserve it, but we have accomplished and survived plenty. Probably

[@BigZebraCom]

Issac covers all the bases. He writes about mega structures we might build in the future...to the mega structures aliens have not built yet.

[@barryon8706]

My solution to the Fermi Paradox: All civilizations advance to the point where they discover qlerb, and then someone with access to a college chemistry and physics lab can destroy the solar system they're in. Qlerb is a lot easier than interstellar travel or megastructures; I'm surprised we haven't discovered it yet, since we already have the baking soda and mimes.

[@qlai3155]

what

[@Evil0tto]

Qlerb was actually the cause of the Tunguska blast of 1908. And that was just a teaspoon that someone added to some tea as a prank. It's true! Don't you people read history?!?

[@Michiganmayor420]

Qlerb: urban dictionary An awkward bonner

[@Crosbie85]

What

[@csgowoes6319]

Oh god, now you've given it away.

[@anthonyandrade5851]

I don't know why, but I always felt you and Rob as kin spirits!Nice to hear about his channel here. You guys should definitely team up some day. Now back to the rest of ou the video

[@Cranberrie123]

I think the most reasonable answer, lacking any other evidence, is life being very rare and taking a long time to pop up, combined with the incredible distances involved. It may be that there are only a very small amount of other life-supporting planets in our galaxy, and because its so rare that means they are all very far apart. If the numbers are lower, it makes it more likely as well that the other like 3 life-supporting planets maybe just dont have advanced technology yet. Or maybe they do and we just havent recieved any messages from them yet, because they are hundreds of lightyears away. Its easy to forget that we have only been searching for aliens for what amounts to less than a century, which is nothing at all on galactic timescales. Its also quite likely there is life in other galaxies as well, but with FTL likely being impossible trying to travel or communicate between them would take thousands of years. We wouldn't know yet for hundreds of years if an alien civilization from another galaxy attempted to communicate or travel here.

[@donkramer8848]

I feel like true interstellar travel would only be solved by a “rogue star” civilization, the need to get to another area of space to survive would be imperative and perhaps drive the civilization to come up with true speed, we lack the drive when stars are so close, relatively speaking

[@stardolphin2]

Even 'relatively speaking,' I think you overestimate the patience of anyone even here inside the galaxy. If 'true speeds' (whatever that may mean) are possible at all, we'll figure it out.

[@jedaaa]

There's another way it can be done, let's say we are one of the first intelligent species the universe has so far produced and there's nobody out there to meet yet, we could find a rogue black hole that's traveling in a direction we're interested in, or a relatively stationary one, then we simply park our spaceships as close to the event horizon as we can, time would almost stop for us, but the outside universe would evolve and produce many thousands of space faring civilizations over millions of years, then we leave our black hole and go join the party and say hi to everyone

[@alainmilette6460]

Why would an alien species not have a life span orders of magnitude longer than our own though?

[@jedaaa]

@@alainmilette6460 could have, I mean even we could be right around the corner from genetically modifying out our age related genes

[@LaserGuidedLoogie]

Fire Upon The Deep is one of my favorite sci-fi stories about finding alien artifacts, and in particular, its perils.

[@isaacarthurSFIA]

Vinge has an amazing mind.

[@daryleldridge7769]

Great episode Iisac, I love the fact that Imagination creates ideas(and technology)...You turn what appears to be pure Fantasy into a genuine plan to accomplish a seemingly impossible task... It makes the future seem so much closer...Thank you..!

[@mikepowell8611]

Why do people keep thinking the Universe is old? Its practically brand new! Earth only formed 4.5 billion years ago and its didn't have life on it for most of that time. The whole universe is only 15 billion years old. It will have a lifespan of 100 trillion years.

[@outrageous-alex]

It's not that it's old. It's that it is old enough for us to arrive, we might be early, but to assume we are first is...unlikely.

[@marlonlacert8133]

From a big idea showing to a Mega Idea Show! Thanks for all the fine work!

[@kobebarka8633]

It’s my birthday today and I couldn’t be more happy to celebrate with you guys! Live long and prosper my friends 🖖🏻

[@isaacarthurSFIA]

Happy Birthday Kobe :)

[@kobebarka8633]

@@isaacarthurSFIA thank you so much you made my day!☺️

[@davidk7212]

Issac, you are truly a credit to your species and your civilization.

[@howiefuzz6894]

"Your" species? Not "our" species? I think I found an alien, everyone!

[@davidk7212]

@@howiefuzz6894 uh oh

[@jackb3493]

How about the acceleration of expansion in the universe as an example of the Time Elapse Argument? I haven’t found myself agreeing with any models that plausibly explain the expansion to be speeding up. Perhaps some technology every civilisation comes across shortly after becoming space fairing. Or maybe we just missed it and are late to the party. Or perhaps it’s just space molluscs

[@dennisjames9091]

After not watching Isaac's videos for a few months, today I have immediately noticed an improvement in his speech and especially tempo of speech which is slower and thus much easier to follow. Thanks for your continuous, consistent and incredibly interesting content, Isaac !

[@maxhocks2006]

Shout out to comics explained. Another great channel. I love that Issac listens to rob. Comics do some wild stuff, but honestly the space sides of marvel and dc are more like what the universe would be like if we didn’t have the Fermi paradox. Lots of massive alien empires out conquering, warring, and building out there.

[@Vjx-d7c]

It's that time of the week again. Thank you for blessing us with this masterpiece isaac❤

[@davidhoracek6758]

Isaac, I would really love to get your take on Robin Hanson's grabby aliens paper. The Rational Animations youtube channel has two good episodes on this, but Robin did a good interview about it on Lex Fridman's podcast, but I expect you wouldn't have trouble understanding the paper. For my money, I think that it should be the basis of all future Fermi Paradox discussion.

[@isaacarthurSFIA]

I just got done writing an episode on it last week, it will be out late September :)

[@gzbd0118]

Hanson's work was not some big breakthrough. People like S. Jay Olson have been doing similar work for years. Hanson (though working independently AFAIK) mainly presented known results in a nice way and made a few simplifications to sharpen the model. I agree that the Olson/Hanson framework is a good modernised way of framing the Fermi paradox, I just like to see attribution where it is due. :)

[@lukasmakarios4998]

The thing about FTL and/or Time Travel is that it SOLVES the Fermi Paradox. If we invent FTL spaceships and go out and find no one else out there, then that proves we are the first. If we get time travel, and find no one, then we are the ONLY ones. Thus, Arthur C. Clarke's quip becomes truly profound. "Either we are alone in the Universe, or we are not, and either case is really scary."

[@robertgraybeard3750]

at ~3:20 you used the term "clade" which I'd never heard before - I must have a minimal knowledge of evolution. Of course, a multi solar system civilization, over time, would have a clade. You and your team have a breadth of knowledge so, of course, you produce excellent videos.

[@jackb3493]

*the more you know jingle plays

[@robertgraybeard3750]

@@jackb3493 Ha as in "the more I learn, the more I learn there's more to learn."

[@derrickthewhite1]

I think he's borrowing from David Brin's "Uplift" series. Or perhaps from works that came after, like Orion's arm.

[@mineown1861]

It's very human to imagine that every other species would evolve to have the same expectations or goals . Maybe that's the first hurdle to overcome .

[@domusavires19]

I don’t think absent megastructures is indicative of a lack of advanced alien life, I honestly just think megastructures are impractical and such enormous feats of engineering most civilizations don’t bother with them. Why would you build a Dyson Swarm or Sphere when you discovered pure fusion or some other power source that provides far more energy than you will ever conceivably need? As for living space the more advanced we get the lower and lower our birth rates seem to fall, and there are countless worlds out there for expansion not to mention space habitats that can be built.

[@ronalddecker8498]

About birth rates … see Carl Sagan’s quote about population. Zero population is a prerequisite to exploring interstellar space.

[@domusavires19]

@@ronalddecker8498 You would think it would be the opposite, if your at a stable population level there would be almost no incentive to colonize and expand, where as if you are suffering from overpopulation you would want to expand and settle to bleed off excess population pressures. If we are at stable levels and ecologically conservative then there really is no need to ever leave Earth, we just make sure no asteroids wipe us out and we are set.

[@cosmictreason2242]

If you have unlimited power then you ABSOLUTELY build a Dyson since it takes no effort. You can’t have your cake and eat it too. They can’t be too much effort for a civilization with cheap energy. Do you know what happens when cars are cheap? Derbies. Do you know what happens when guns are cheap? Shooting competitions. Do you know what happens when bread is cheap? Cooking shows? And what do you think happens when space rockets and robot engineering is cheap? It means instead of building legos, your building city sized habitats for FUN

[@hunterchristian8372]

Gosh, I keep switching your videos I watch between old ones from 7+ years ago and new ones and the quality difference is astounding.

[@edwardmurray2284]

Hey Isaac. Have you done a video on the minimum size a life form would have to be to reach technological advancement?

[@isaacweaver2765]

The past two episodes, including this one, do not show up on apple podcasts or spotify :(

[@Gauldame]

"why didn't the other aliens build mega structures..." You see, they never developed microtransactions in video games and are contently playing their video games on renewable resources. Truly alien psychology.

[@sarveshyadav01]

lmao

[@MogofWar]

Ah yes! Vidya is the true great filter and microtransactions are the key that picks the lock.

[@quito787]

I love stuff about the fermi paradox. We're all quick to discredit Malthusian thinking (including me), but I think it's a mistake to rule it out. Humanity has been lucky that technological innovation has enabled us to keep a constantly growing world population fed, but we've seen how fragile things can be-- major disruptions to the supply chain due to the pandemic, or war affecting countries that are major suppliers of grain/wheat, can result massive food shortages. With a much more deadly pandemic or another future world war, we may suddenly find ourselves with a global famine. This may happen to us or to any other civilizations that may spring up in the universe. Imagine somewhere else in the universe where there is a world civilization where they do not manage to make agricultural breakthroughs, or major disruptions to food production and distribution happen, and they fail to keep their growing world population fed, so they never progress to the scale where they are able to build detectable megastructures. I believe civilizations need to reach a certain scale in order to be in a position to build detectable megastructures.

[@JoeCensored]

I'm thinking the assumption that advanced aliens would build detectable megastructures is false. As human technology has advanced we've favored smaller and more efficient rather than larger. Cars for example are considerably smaller today than the 1950's. Our communications have moved towards directed point to point, away from high powered omnidirectional. With this trend continuing I have doubts alien communications will be something that spills out over thousands of lightyears for us to pick up. Doing so is incredibly wasteful energy wise. I expect advanced aliens to favor efficient structures only as large as necessary for their purpose. This probably means we cannot detect them from a large distance.

[@andrasbiro3007]

But then they'd just build a shitload of them, with combined mass and size comparable to traditional megastructures. The point is that if a civilization grows consistently, and has access to space, eventually their presence will be detectable, regardless of what they do, simply due to the scale of their activities. And the desire to grow comes from evolution, so it should be very common. Plus a single civilization is enough to colonize a galaxy in just a few million years. Even if they have absolutely no use of stars, or interstellar gases, they would likely still tamper with them. Just like how we rarely leave our environment in it's natural state, even if it has no practical use. For example you very likely don't want supernovas in your neighborhood, or dense dust clouds on your highways.

[@atk05003]

Isaac is also assuming very efficient devices. In this context, astronomers would expect to see an unusually large infrared (heat) signature, because even a very efficient device has waste heat (under known physics). The reason we think we could possibly see these structures is because we assume that other life would try to expand their collection of resources and space. This assumption is based on our understanding of natural selection, which seems like it would apply on other worlds as well. Given an expanding population, we think a sufficiently advanced species would try to gather more resources and even create more space (habitats). If that continues long enough, you end up absorbing and using a large percentage of the light from your sun. At that point, your system would have a really large heat signature compared to the apparent brightness of the star. So, yes, these expectations are built on assumptions, but those assumptions seem likely to hold true for at least some other species, because they seem to hold true for us.

[@charliecoesr7921]

I would think they would have recycling perfected so why leave resources behind?

[@JackSparrow-re4ql]

Yes, this is precisely the reason why our truck convoys, railways and cargo ships have reduced to an indetectable size! They also use optic stealth camouflage! Its not like a galactic shipping lane in space would be busy and big enough to spot or anything. And its not like big clunky technology for shipping; like trucks; haven't changed much over the years because they're cheap,bulky but useful old tech...

[@dibbidydoo4318]

how do you expect for aliens to get energy of an entire star without using technology beyond known physics or a megastructure?

[@casualgoats]

Literally the best content to listen to while i weld at work.

[@sulljoh1]

I love the phrase "Grabby aliens"

[@thehand7902]

It's cutesy but also makes me think of aliens that literally "grab" like The Thing or the creature from Carrion.

[@HogbergPhotography]

@@thehand7902 Yea or an alien "groping" me 🤪

[@sparksmacoy]

Hi Isaac, can you do a super detailed look at possible uber recycling methods what will be needed on the first deep space missions? I have always thought that the machine reliability and recycling proficiency problem for deep space missions is an under-appreciated issue. Love your work btw, this channel could form the basis of some pretty incredible movies.

[@vipondiu]

Sign me up for "Colonizing quasars"! and how about "colonizing neutron stars" or "colonizing pulsars"?

[@unkledanbot]

Dude, comics explained is way better than actually reading the comics

[@03chrisv]

Any civilization capable of building mega structures like Dyson swarms, Halos, etc probably deem them impractical or not worth the effort. They might have come to the conclusion that building their own Matrix or simulation world is more beneficial to their happiness and easier to accomplish.

[@cosmictreason2242]

Not worth the effort implies resource scarcity. If there’s no scarcity, literally anything is worth the effort

[@03chrisv]

@@cosmictreason2242 I don't agree. Time is the ultimate resource, not chunks of ore. Just because a civilization could build such structures doesn't mean they would or think it's the best option for them. If it takes centuries or even several millennia to build these planet or star sized mega structures they might find better ways to utilize their time. It's more likely they would create simulated paradises in their own version of the Matrix rather than building giant mega structures. It would also be a possible answer to the fermi paradox, the reason we don't see them is because they decide it's better to cut themselves off from the universe. Sure maybe they have probes out in space checking things out but they're not concerned with physical expansion and consuming resources throughout the galaxy.

[@cosmictreason2242]

Again you’re trying to test it as of time is scarce but why would it be if you’ve got robots

[@03chrisv]

@@cosmictreason2242 For mega structures to be feasible the civilization would have to have more of a hivemind with a unified goal and vision that can endure tens of thousands or even millions of years. Sure they could have robots build a star sized mega structure for 10,000 years, but will any of their descendents care? Will they change their mind? Will the culture and belief system change during those years? If they defeated death or live for thousands of years you might be able to make a stronger case, but even then it will be tough as new members of their society will undoubtedly be born constantly adding influence and change to the status quo. Building inwardly and simulating paradises in a matrix would probably be easier, use less energy, and offer them more happiness than building outwardly and possibly giving themselves away to a possible threat. It could be a dark forest out there.

[@cosmictreason2242]

@@03chrisv you don’t need a hive mind, you just need a large enough population that a small percentage of the population can be sufficiently large and resourced to engage in the effort. With 10 billion people, we have 3 billionaires trying spaceflight and one of them being really effective. With a thousand times as many people, 10,000 Elon musks means we’re colonizing the solar system

[@Hriuke]

Where do the graphics in these vids come from? They are amazing.

[@kiri101]

Malthus was only concerned with the reproduction of the poor, and so are most people who knowingly or otherwise regurgitate his argument since. He was proven wrong in his own time and that hasn't changed.

[@MrMichiel1983]

Didn't hear that. Could you relate some of that proof?

[@neeneko]

Yeah, it is always kinda creepy hearing people talk about Malthian ideals in progressive circles given how tightly tied it is to things like white supremacicy and eugenics. The whole idea was 'if there are too many brown mouths to feed it will ruin our race's future!'

[@MrMichiel1983]

@@neeneko Do you have some sources? Most people discuss Malthusian crises in the context of exponential population growth with linear technological progress. If, for instance, this has impacted evil stuff like Social Darwinism. I am interested where to read more of this. The whole idea was not about color at all, given my reading of the topic. So this is interesting.

[@MrMichiel1983]

@@neeneko Also, where I am from mostly people in conservative circles have the disposition that color matters.

[@Nutroyalty]

@@MrMichiel1983 lol you rly tried to get sources? They have a justice boner and are talking out of their ass. They have no sources, because infographics posted on social media can’t be cited.

[@PBCSandMarci]

How well would we be able to detect a megastructure 5,000 light years away? Idk if in these couple years that we have had advanced equipment to detecting such stuff

[@isuckatusernames4297]

as well as whoever built them 5000 years ago could see them from the nearest planet. meaning that they could exist, we just can't see them for the next 5000 years

[@user-cw5nv6eq1v]

Honestly I think the rough definition you laid out for what you mean by “civilization” is so insightful, and ought to supplant the term’s common usage. I’d argue that such a continuity of intelligence and information exists within different language groups, such as the Anglophone. The concept emerges most clearly when a very large group of people have sustained and frequent contact with each other - perhaps necessarily aided by shared technology and economy. I expect that we will one day have a more or less unified human civilization: less in the political sense, moreso a continuity of intelligence and information.

[@Lusa_Iceheart]

Yeah in a political sense, I highly doubt we could ever manage a 'United Nations of Earth' sort of Star Trek government. But in stuff like technology, information, media, trade, and even a lingua franca yeah we have that to a degree today and have had high levels at multiple periods in the past. The Bronze Age saw very intricately connected empires, economies and travel from what is now Afghanistan to Iberia and even Cornwall. That tin trade was big money back in the day. Later on in the late Roman Republic Early Empire period we see that widespread, interconnected 'civilization' once again. Chinaware would be traded in India and go up the Red Sea and get sold in the markets of Constantinople. Trade has always been a hugely important facet of linking cultures together, I doubt that will change in the future.

[@scottrotherham]

Hell of an episode, amazing work you lovely people

[@HugeGamma]

the bread and butter topic

[@ladyattis]

As to the question of Malthusianism and growth. The issue really is that we've often confused growth for development. Getting a faster CPU doesn't mean you suddenly needed more resources to make the CPU. In fact, many developments in the past and current times have caused a massive reduction in material requirements which has been probably the most important aspect of our economy. Now as to the question of growth, that's largely going to track probably a linear to sub-linear (probably logarithmic) scale rather than exponential or higher rate. As we see even today population growth curves have been flattening worldwide and not due to pandemics, wars, or comets smacking us a good one. We just start to settle as a people and focus more on ourselves than no raising kids. Now this might come back to haunt us but for now it seems we're still growing enough globally to exceed replacement numbers but without the so-called population bomb that everyone was so scared about. Ultimately, if we're to discuss resource wastage, that's something to do with the problem of capitalism and the false sense of the nearly unlimited scales of economy (mostly due to state interventions in transportation costs and the like), and it's not really an inherent problem with being a technological civilization. Hence why I distinguish between growth and development.

[@spartanalex9006]

I describe the Malthusian argument as Economics by people that don’t understand Ecomonics.

[@cosmictreason2242]

There is no “problem of capitalism,” quit reading Marx and read Adam smith or Thomas sowell. Unless you have an AI better than the one in Person of Interest, You cannot have a planned economy that’ll do better than individuals making free choices about what tradeoffs have the most value to them. If your only problem is human free will, that’s a feature, not a bug

[@poisontoad8007]

The more I look into this paradox the more I think we might be it. In our galaxy anyway.

[@Electronic424]

I like how you sponsor Event Horizon, you two are my go to choices

[@JohnnyWednesday]

I personally believe that, given most habitable planets are more massive than earth and the rocket equation doesn't allow them to achieve orbit - that the majority of civilizations advance their technology on the ground to the point where access to space isn't required or desired.

[@jakephelps4924]

Something like Project Orion would still work on higher g planets. Or maybe given enough millennia technology will be able to find a way to cancel gravity so that you can make it to orbit on a few gallons on fuel. Or a centrifugal lauch system could be used where the bulk of the acceleration needed is attained before even leaving the ground. Options exist for high gravity planets also. And 2 or the 3 i just listed are already possible with our current technology. There may be many other possible options as well.

[@bootstrapbill447]

In addition to Orion, Lofstrom loops and any other active support structures are also all perfectly viable in any amount of gravity, just requiring more energy to power

[@JohnnyWednesday]

@@jakephelps4924 - Certainly they could access space - but if the technology that lets them do it comes after a better option? they may never want to.

[@JohnnyWednesday]

@@bootstrapbill447 - Yes there are options - but they may have invented better options before access to space becomes practical. Or indeed perhaps they all hit an extinction technology before they reach space. Maybe the 'great filter' is the size of the planet restricting space and promoting localized AI

[@cripplingautism5785]

"given most habitable planets are more massive than earth" what is this based on? just the amount of larger planets in a circumstellar habitable zone? larger planetary size comes with its own issues such as too much water and other volatiles and losing less of them over time, and being a bigger asteroid/comet sponge. also there's a bias in observed planetary sizes because it's simply harder to detect smaller ones.

[@digigeek19]

In this episode: Isaac Arthur takes off the gloves and starts bare knuckle boxing bad Fermi paradox solutions. Every blow hitting like a sledge hammer.

[@nicholascarter9158]

I think the infinite miscibility problem is the one we have grappled with the least. I think that if you defined Earth like planets as "a living creature from earth can survive on this planet with no additional infrastructure" that you might find the diversity of planetary conditions so great that, even given the trillions of stars in the universe, a truly "earth like" planet might occur only once every 1,000 light years. I think what happens to most species is that they don't have the power to leave their star system. But what I think happens to the rest is that miscible planets are so rare, and environmental engineering so materials intensive, that the two or three planets they're able to colonize each succumb to their own independent extinction event, leaving behind a wandering population that can't sustain the species. I think the universe is a graveyard, and that what we would find if we could explore other stars is unintelligible structures on planets that could never support human life. The headstones of civilizations that died anyways.

[@Comicsluvr]

Without all of the math (which I'm terrible at), just the ideas that come from most of your videos are mind-blowing.

[@nathanhearn356]

What is more logical? That a species will grow so far beyond its means in terms of numbers and resource consumption until it has to churn an entire solar system or multiple solar systems to accommodate its increasingly unsustainable growth rate and consumptive lifestyles? Or, that a species will eventually learn to live well within its means with a sustainable population and lifestyles suited to its environment and not the other way around? Putting aside that building megastructures requires power sources and meta materials humans aren’t really close to producing, the very logic of extra planetary megastructures may simply be flawed and owe more to science fiction and wishful thinking that logic, much less the laws of physics.

[@dipanjanghosal1662]

Exactly. Megastructures simply feel... obsolete for any "advanced" civilizations because advancements always leads to efficiency.

[@bardlemon5635]

Thank you once again for making my Thursday yard work more bearable. Excellent content.

[@dawall3732]

I think the term you're looking for is Polity. That is generally used for a type of government or a specific nation. It can also be used for as a synonym for civilization.

[@cthulhufhtagn7520]

Or culture

[@dawall3732]

Of course Polity also can be used to identify the end of a Civilization or nation because it transitions into a different form of government. Such as Rome transitioning from a Republic to a Imperial system with An inheritable title of emperor. Or the reverse can be done such as happened in Russia when the Xars were deposed and the Monarchy system was replaced with a Republic Communist system. Under the term Polity these can both be described as the end of a civilization and the beginning of a new civilization. It can also be used to describe the end of a civilization through violent means as well as Non violent means. A fictional example of a non violent one would be the Star Wars transitioning from a Republic to an Empire when they voted chancellor Palpatine into the emperor. A violent example in the exact same setting would be the rebel alliance using gorilla and terrorist tactics to overthrow the Empire and replace it with the New Republic.

[@ssshhhjjj192]

I got my drink and my snack! Thank you for your videos Isaac!

[@owenliquidnitrogen]

I think we live with a ton of other civilizations on about the same tech level as we are, more or less. The problem is simply time. Even if a world reach space and branch out right now, it may still take several thousand years and more before we see them, or they see us.

[@69Kazeshini]

I can't remember which youtube channel spoke about it but a guy said if we were to crawlinize a galaxy in just a straight line from end to the galaxy to next, it would take somewhere between 200,000 to 500,000 years to accomplish that and that is only in a straight line not spreading out all over. So it might be that they are 100,000 light years away and we just don't know.

[@electroflame6188]

Several thousand years is utterly insignificant on astronomical timescales. If civilization was common in our galaxy, it would be very visible to us.

[@JustinBuildsThings]

strange question, but if FTL has implications like the ability to break or screw with chains of causality where things like FTL ships communicating with sublight ships being able to do things like deliver the recept to a message before the original message gets sent, do these kinds of issues have a potential impact on the fermi paradox? thats something ive never seen addressed anywhere in a fermi paradox video, assuming ftl is possible

[@Gary-Seven-and-Isis-in-1968]

Unless the Universe is the Alien megastructure. 🤔

[@jdlech]

A megastructure would be designed and built to last thousands - perhaps even a few hundred thousand years. But they're not eternal. Even our pyramids, while an impressive 7000 years old, already show signs of severe damage due to erosion. Megastructures suffer the same fate, whether by meteors or radiation or corrosion. Even self repairing systems will break down eventually. And then there's the builders themselves. 10,000 to 100,000 years of research and development and social progress is likely to leave their megastructures behind, having been made no longer necessary. Eventually, the megastructure would be abandoned, demolished, recycled, or left as a museum piece. This is something many people fail to consider - the effect scientific progress has on the evolution of a sentient species. At some point, a species takes command of its own evolution - either vastly accelerates it, or takes it in wildly divergent directions, or both. Tens, perhaps hundreds of thousands of years of self directed evolution is likely to leave a species unrecognizable by its distant ancestors. Ourselves included. Assuming we survive ourselves, it's very unlikely that we will have any need or use for physical bodies, space or physical resources a hundred thousand years from today. What megastructures we build will be museum pieces, anachronisms, merely a testament to a bygone age before we ascended beyond the need for such trivial things. And it's very likely also true of any sentient species that has gone before us.

[@RazorbackPT]

Grabby aliens episode when?

[@RazorbackPT]

Yes! You mentioned grabby aliens in the end, awesome! Can't wait.

[@hotwheels2621]

28:34 to 30:30 For those who want to share with their friends one of Isaac’s most potent speeches yet.

[@ronalddecker8498]

“No civilization can possibly survive to an interstellar spacefaring phase unless it limits its numbers. Any society with a marked population explosion will be forced to devote all its energies and technological skills to feeding and caring for the population on its home planet. This is a very powerful conclusion and is in no way based on the idiosyncrasies of a particular civilization. On any planet, no matter what its biology or social system, an exponential increase in population will swallow every resource. Conversely, any civilization that engages in serious interstellar exploration and colonization must have exercised zero population growth or something very close to it for many generations.” Carl Sagan, Cosmos

[@cosmictreason2242]

Fake news. The more people, the more productivity, the faster you get off the rock

[@erickbrand6966]

Excellent video graphics on this episode Isaac!

[@AF-tv6uf]

Every potential megastructure is explained away as something else because it's taken for granted that it being a megastructure is inherently the least plausible explanation for the phenomenon. That's quite the potential oversight. But, then again, we're a young species.

[@Falcodrin]

Hey first video I have watched in a while (been distracted) and I just want to say the rhoticism is basically invisible now and congrats on the work of the efforts I know you are putting in! You might be internally judging yourself like everyone does with their own body weight or facial appearance but just wanted to say that from the outside its amazing now. Your voice only has a small hint of muddiness and your Rs are solid. Love you man

[@ysonokosan]

You touched on it a few times, and it's the theory that most likely explains the fermi paradox aside from there just isn't any life visible to us with our current level of tech. It's that we're in some kind of preserve or zoo. Along that line, it'd be relatively easy to project some version of a universe at something as small as our planet, or solar system. If aliens wanted to hide us or themselves from what's going on around our region of space. I'm not 100% convinced this is the case, but it serves as an interesting idea until we can get out there far enough to disprove theories like this. In all likelyhood, we are just the first form of life to arise in this region of observable space. The universe is vast, and likely holds many forms of intelligent and advanced life. The odds that any of us would be clumped together, or be near enough to observe each other might be low though. Once you consider all of the filters and factors for intelligent or advanced civilizations.

[@0ctothorp]

I think he did an episode on the zoo hypothesis, I'd go watch that one I think you'd get a lot out of it.

[@AnthOny-gl7lj]

You’re the best. I’m obsessed with you. Great channel. And thank you

[@dawall3732]

Any thought given to the concept that extreme collectivism could be the answer to the fermae paradox? What I mean by this is utilizing the data network of the species to create an ever increasing level of interconnectivity until the (I) dissolves into the (sea of we) creating a hive mind that eventually evolves back into the (me). The me eventually discovering it is truly alone and suffering all of the psychological effects that the individual would suffer under such a situation until it either chooses to waste away or end its existence. We are fast approaching a technological capability that would allow the existence of such an (individual) composed of an entire species now. It is theorized that we will reach such a technological capability either just before we reach cardichev one or shortly after we reach that stage of civilization. I based this theory on humans being composed of individual cells combined together to create a collective consciousness known of as a human being. Though these individuals are composed of Possible trillions of cells they are capable of self destructing if forced into a state of prolonged isolation which can cause depression. Imagine a collective consciousness produced from the combined consciousness of an entire species. It would most likely have the starting point of that species social nature as a fundamental part of it's psychology. This means that it would be an individual that would find itself composed of trillions of cells suddenly looking around and realizing it is alone. All possible searches for anyone or anything to communicate with and interact with on the same level would be light years away. If it could find a possibility for such at all. So it is possible that such an entity would begin shutting down and withdrawing into itself until it waste away. Or it could possibly self terminate. Just like individual humans would under similar circumstances. It is perhaps depressing or horrifying to think about but if true it means that most civilizations would never really make it past the beginning stages of a type one civilization. If our own technological development is any measure to judge.

[@cosmictreason2242]

Sounds like you’re reading too much commie fanfic on tumblr tbh lol

[@dawall3732]

@@cosmictreason2242 I've actually never read any fan fiction on Tumblr. I got the idea while watching Johnny namanic starring Keanu Reeves.

[@cosmictreason2242]

Hm, haven’t seen it so I don’t know the reference. Still know that mind control is not a positive future but a dystopian horror

[@virutech32]

Hive minds would have some aversity to traditional exoansion, though not resource harvesting, but pretty much every step of this is an assumption with no precedent since cells are not an adequate analogy for an entire generally intelligent creature & we have no adequate analogies. Baseless assumptions about hive mind poperties aside, this would also require that absolutely everyone, without meaningful exception, join the hive mind...every time...in every civilization...regardless of psychology, environment, or evolution...idk seems pretty implausible to me.

[@dipanjanghosal1662]

I too have thought about it and it seems plausible. The way we humans are going, in a few thousand years we'll surely become digital conciousness and then become a part of a hivemind and then eventually be merged into a single digital being. Civilization always leads to centralisation. Look at the world right now, the govt is becoming more and more powerful and individuals on avg are becoming less and less significant. This will happen. Only a matter of time.

[@prolamer7]

I think that by the time civ can build star size megastructures technology is so advanced that for one or other reason there is no practical need to create one. Yes there still be some megastructures build but for wholy different purposes than to collect heat from stars. And they be camuflaged via some kind of forcefields so someone else doesn't see them and FTL near them to destroy competition... here you have one of many very simple solutions which i conjured in just few minutes.

[@jwg72]

I could definitely see a culture viewing the natural progression of the world as sacred... the argument about slowing entropy should appeal to some variant of some portion of some alien species... which means that we should see something in some surrounding galaxy... if we don't, that should be a very worrying increase in the fermi-paradox (there are easy explanations for our own galaxy, e.g. abiogenesis being almost impossibly unlikely etc. But it gets harder if there are 10,000 galaxies which show the same lack of von Neumann anti-entropy probes)

[@ErinsAaron]

My social media is covered in links to the D&D movie trailer; but, this is the video I've been excited to watch all day.

[@WiseOwl_1408]

Maybe nothing is out there at all. Intelligent life must be very rare. Even rarer to leave a planet.

[@Teknokraatti]

The whole point of the Fermi paradox is to find out exactly why there either seems to be or is no other intelligent life in our relative vicinity as understanding that 'why' is of significant interest and importance for the one, sole species if it wishes to survive.

[@cosmictreason2242]

God made humans on only one planet, like he said

[@Teknokraatti]

@@cosmictreason2242 There's literally 0 reason to expect that the alien life we might one day find or encounter would be humans.

[@WiseOwl_1408]

​@@Teknokraatti the whole point is to make KZbin vids for $$$. Nothing comes from wanking online

[@uncleanunicorn4571]

There's still time for us to devolve into mutant cannibals. And for aliens to get bored with us.

[@WarlockHolmes420]

I just don't get the Dyson Sphere at all. I don't see how we could beam the energy back without blowing up the planet. I don't understand how it wouldn't just ruin the entire solar system or even the need for it. Let alone building something that huge and pointless. I think it's a stupid idea and always have. Love your channel though.

[@wobogoat3379]

Same here. I'm convinced there are advanced civilizations out there but they are ai based. So they will use mostly low energy nanotechnology and not megastructures near hot stars.

[@NoName-ze4qn]

Maybe the energy is used by the sphere itself for some purposes like computation.

[@maltheopia]

1.) Why does the energy need to be beamed directly back to the planet? Why couldn't we just transport the energy in the form of satellite relays and/or batteries? 2.) Leaving the Sun alone will kill off our solar system way faster than tampering with it. Our Sun could last for trillions of years at its current output if it was star-lifted. If we don't do anything, its increasing intensity will kill off all higher life in 500 million years and will definitely kill off all life in at most 5 billion years.

[@maltheopia]

​@@wobogoat3379​ Even if you've mastered entropy and have a free source of unlimited energy that takes little effort to get and you're an AI civilization and are about as small as you could get -- you still have a very good reason to build megastructures; not to obtain resources, but to extend the lifespan of stellar objects. Indeed, an immortal AI civilization that doesn't need or want to colonize the galaxy might still want to do it just so they can extend the life of stars, crack the ice shells of ocean planets, terraform dead worlds, provide resources for latecomer civilizations who find themselves in a dying galaxy, split binary stars so that their orbiting objects become more stable, etc.

[@wobogoat3379]

@@maltheopia good points. But why should an AI terraform or crack ice shell moons on a regular basis? An AI should prefer extra cool environments for computation reasons. So an AI would probably prefer Titan or the oort cloud. An AI would explore the universe by nano ships. And if an AI would seldom harness a sun, it would probably uses a dyson swarm (visible only as dust), not a megastructure.

[@ClanHawkins]

If I wasn’t a long time subscriber I would h e done so now! “Speaking of subscribing to the other channel, why not practice subscribing to this channel?” Best Call To Action! Thanks for a Len enjoyable thought provoking episode as always!

[@nO_3Xcuses]

Finding alien structures in the vast darkness of the universe would be like locating a particular grain of sand on the ocean floor

[@Arander92]

THANK YOU! The Fermi Paradox makes no sense

[@PhilipMurphy8Extra]

A Isaac Arthur video on a Thursday is awesome.

[@internationalartprojects8660]

I think the Dinosaur Meteor extinction event answers all those questions regarding the lack of alien civilizations. Without a 1 in a million trillion chance of a meteor hitting the planet and killing off the dinosaurs humans would never have evolved and thus intelliginent life. Perhaps life evolves similarly on other planets and the crazy coincidence of factors are so small that intelligent life and civilizations is rarer than people think.

[@ryalloric1088]

But why do you assume dinosaurs could never have evolved intelligence, given the opportunity? Look at what our ancestors were like back then!

[@cosmictreason2242]

If the probability rises to 1 per 4 billion years then there should be billions in the Galaxy and it should already be colonized

[@sharmakefarah2064]

The biggest reason Time Travel/FTL solve the Fermi paradox is by breaking the thermodynamics issue. Since we ditched the conservation law with time travel, they don't need to be in our area for any timeline. In fact the key thing that would be rare is a non-time traveling civilization accidentally seeing a time traveling civilization, since again thermodynamics no longer holds, and thus we can't guarantee seeing them at all, and they might be out of our universe as well.

[@cosmictreason2242]

He’s addressed this too. If they have ftl then they absolutely would’ve visited us, since travel has no cost

[@sharmakefarah2064]

@@cosmictreason2242 The biggest reason it solves the paradox is his entire Fermi paradox series relies on thermodynamics making sure we can always observe them and that they'd be forced to make megastructures. But in the absence of thermodynamics and the time travel issue, we can't even see their heat at all, and is there any motivation to come to us, when they are instead exploring black holes? Probably not. We need to remember that the Fermi paradox has a massive load-bearing assumption of thermodynamics being true and no FTL. Without those, there is no reason to go anywhere except black holes, and they are living in virtual universes in Closed-timelike Curve computers, which need nothing to dissipate heat, making them undetectable.

[@cosmictreason2242]

@@sharmakefarah2064 us existing is a sufficient reason to visit us. Especially with free energy and ftl

[@billmiller4972]

Those civilisations must have reached at one time of their history a point where they needed to economize (like we today) and stop breeding and multiply. When/if those civilisations managed to maintain a technical civilisation they stopped needing vast amounts of energy or materials. So there is no need to build such structures.

[@SilverMKI]

Stability is unstable given enough time - it only takes small incremental changes in attitude through the generations for those changes to add up quite rapidly, on universal timelines. Or as discussed, some element of that society splits off and starts accumulating resources and expanding population and becomes the dominant faction as they outpace the former dominant culture.

[@NerfAlice]

Not even playing I typed so many thing's in to find you. I'm so glad I did I enjoy listening to you!!!!

[@Psnym]

Let’s take extra good care of the planet we actually have

[@petersamson5407]

I think it’s sociology combined with the rarity of life. If there are social reasons why megastructures would be extremely rare, those are enough to explain Fermi’s paradox if life is extremely rare. Extremely few civilisations + very low sociological likelihood of megastructures = well, empty space.

[@SockPuppet80]

"Leaving a star untapped just doesn't make sense." Sigh. I'd hoped that in this episode, Isaac would finally step out of his intellectual Dyson bubble and consider alternate perspectives that alien beings might take. But no such luck. I'm afraid he'll never quite get how _deeply weird_ his position on the inevitability of obsessive energy hoarding is. (And I'm saying that as objectively as I possibly can.) Yes, intelligent entities might need a way to psychologically countenance Entropy, and yes, that might involve trying to immanentize their brief lives through stellar architecture. But for crying out loud, man, that is by no means an inevitable outcome, nor even a necessarily probable one! You're projecting your own hangups re. waste and growth onto beings about whose psyche we know less than nothing! Your perspective on what is "logical" and "rational" is warped because everyone's is - our minds and experiences inevitably create an intellectual event horizon; the more we know, the more difficult it becomes to remember that there is stuff out there that we do not, perhaps cannot know. Still, we must _be aware of these epistemic limitations_ - we must keep ourselves from imagining that our viewpoint is the universally applicable, the evolutionary dominant one. I get it - it irks you that no intelligent life within the observable universe has Dysoned up their stars. You think that this would be inexplicably wasteful of them, fine. But please recognize that your position might be, by our universe's standards, _incredibly weird_ and _exceedingly rare_ too. That there is nothing necessarily "rational" or "logical" about going, "Wow, look at all this energy/matter just lying around, going to waste; I'd better harvest it on a massive scale, visible from millions of light years away."

[@cosmictreason2242]

Life requires energy and anything that doesn’t preserve itself will go extinct, so what exists will by necessity, seem to utilize energy

[@Dan-lt8vm]

Energy is the most important resource in a civilization. Energy is especially important to a space-faring civilization, which would need tremendous amounts of it.

[@cosmictreason2242]

@@hungrycrab3297 do you believe the first 100 people on earth farmed 100 billion chickens? We have 100 billion chickens alive today, getting turned over every 2-3 months. The way it actually works is you make a little more than you need, then you grow the population, then you can handle growing more, and so on it goes. That will inevitably lead to Dyson swarms because there is no necessary barrier to growth

[@cosmictreason2242]

@@hungrycrab3297 secondly you’re not looking at subpopulations. Catholics, Mormons, Orthodox Jews, Muslims and Christian homeschoolers, ESPECIALLY that last group, are ideologically motivated to maximize offspring, and as the mainstream decreases, these will increase their share of the population until the trend increases again.

[@cosmictreason2242]

@@hungrycrab3297 finally, it’s not impossible to build a Dyson because all you need is the ability to build a satellite and put it in orbit around the sun. That’s literally it. From that, a Dyson is inevitable because all you do is keep going

[@reinderknoops1682]

Hi, love you series. ESP. Those on megastructures. Being Dutch and living in the Netherlands I sometimes feel like I'm already living in a megastructure or at least the closest thing we have on earth now.

[@DanGolik]

Narrated by Elmer Fudd

[@johnterpack3940]

I like to say, "just because you can imagine a thing, doesn't mean that thing is possible." It's entirely possible we don't see such structures because those structures are impossible to build. Maybe we are right now living at almost the pinnacle of technology. Maybe we're stuck on this rock and doomed to die here. Maybe that's just the fate of any civilization that arises.

[@shnitzelstiner7094]

Absolute most depressing comment I’ve ever read. None the less, it’s a great counterpoint.

[@johnterpack3940]

@@shnitzelstiner7094 As an empiricist, logician, and realist I hold a lot of unpleasant views. Unfortunately, I'm often right.