The Fermi Paradox — Where Are All The Aliens? (1/2)

Are we the only living things in the entire universe? The observable universe is about 90 billion light years in diameter. There are at least one hundred billion galaxies, each with one hundred to one thousand billion stars. Recently, we’ve learned that planets are very common too. And, there are probably trillions and trillions of habitable planets in the universe. Which means, there should be lots of opportunity for life to develop and exist. But where is it? Shouldn’t the universe be teaming with spaceships? Let’s take a step back. Even if there are alien civilizations in other galaxies, there’s no way we’ll ever know about them. Basically, everything outside our direct galactic neighborhood, the so called “Local Group”, is pretty much out of our reach forever, because of the expansion of the universe. Even if we had really fast spaceships, it would literally take billions of years to reach these places, traveling through the emptiest areas in the universe. So, let’s focus on the Milky Way. The Milky Way is our home galaxy. It consists of up the four hundred billion stars. That’s a lot of stars, roughly ten thousand for every grain of sand on earth. There are about twenty billion sunlike stars in the Milky Way, and estimates suggest that a fifth of them, have an earth sized planet in it’s habitable zone, the area with conditions that enable life to exist. If only zero point one percent of those planet harbor life, there would be one million planets with life in the milky way. But wait, there’s more. The Milky Way is about thirteen billion years old. In the beginning, it would not have been a good place for life, because things exploded a lot. But after one to two billion years, the first habitable planet was born. Earth is only four billions years old, so there have probably been trillions of chances for life to develop on other planets in the past. If only a single one of them had developed into a space traveling super civilization, we would have noticed by now. What would such a civilization look like? There are three categories. A type one civilization would be able to access the whole energy available on its planet. In case you are wondering, we are currently around zero point seven three on the scale, and we should reach type one sometime in the next couple hundred years. Type two would be a civilization capable of harnessing all of the energy of its home star. This would require some serious science fiction, but it is doable in principle. Concepts like the Dyson Sphere, a giant complex surrounding the sun, would be conceivable. Type three is a civilization that basically controls it’s whole galaxy and its energy An alien race this advanced would probably be godlike to us. But why should we be able to see such an alien civilization in the first place? If we were to build generation spaceships that could sustain a population for around one-thousand years, we could colonize the whole galaxy in two million years. Sounds like a long time, but remember, the milky way is huge. So, if it takes a couple of million years to colonize the entire galaxy, and there are possibly millions, if not billions of planets that sustain life in the milky way, and these other life forms have had considerably more time than we’ve had, then, where are all the aliens? This, is the Fermi Paradox, and nobody has an answer to it. But we do have some ideas. Let’s talk about filters. A filter in this context represents a barrier that is really hard for life to overcome. They come in various degrees of scary. One: There are Great Filters and we’ve passed them. Maybe it is way harder for complex life to develop then we think. The process, allowing life to begin, hasn’t yet been completely figured out, and the conditions required may be really complicated. Maybe in the past, the Universe was way more hostile, and only recently things have cooled down to make complex life possible. This would also mean that we may be unique, or at least one of the first, if not the first civilization in the entire Universe. Two: There are Great Filters and they are ahead of us. This one, would be really really bad. Maybe life on our level exists everywhere in the Universe but it gets destroyed when it reaches a certain point, a point that lies ahead of us. For example, awesome future technology exists, but when activated, it destroys the planet. The last words of every advanced civilization would be: “This new device will solve all of our problems, once I push this button!” If this is true, then we are closer to the end then the beginning of human existence. Or, maybe there is an ancient type three civilization, that monitors the universe, and once a civilization is advanced enough, it gets eliminated, in an instant. Maybe there is something out there, that it would be better not to discover. There is no way for us to know. One final thought: maybe we are alone. Right now, we have no evidence that there’s any life besides us. Nothing. The Universe appears to be empty and dead. No ones sending us messages, no one answering our calls. We may be completely alone, trapped on a tiny moist mud ball in an eternal Universe. Does that thought scare you? If it does, you are having the correct emotional reaction. If we let life on this planet die, perhaps there would be no life left in the Universe. Life would be gone, maybe forever. If this is the case, we just have to venture to the stars and become the first Type Three civilization, To keep the delicate flame of life existing, and to spread it until the universe breathes its final breath, and vanishes into oblivion. The universe is too beautiful not to be experienced by someone. This video was made possible by your support. It takes at least 200 hours to make one of our videos, and thanks to your contributions on Patreon, we are slowly able to do more and more of them. If you want to help us out, and get your own personal bird for example, check out the Patreon page.

Comments 91

  • There's brand new stuff in the Kurzgesagt Merch Shop. Check it out here:

  • What if the light we see from other galaxies is just taking so long to travel that by the time they get to earth a civilization there has already started

  • The only life in an infinite universe and we kill each other over petty bullshit everyday.

  • We are the aliens

  • I mean if there's a civilization on the edge of the universe, what are the odds we as humanity could survive 45 billion years, long enough for their radio signals to reach us, and not go straight through a planet on the way over here?

  • I am loving the Stellaris endless space like music

  • Hold up all I see is a blue black hole hold on…

    Wait is that a bad thing?

  • Don't hug me I'm scared reference at beginning

  • About aliens outside the local group and our inability to meet or learn about them
    1. They may already by hyper advanced and on their way here at light speed, it wont take billions of years it could happen tomorrow
    2. If we find a way to travel at light speed we can reach very far away galaxies before they recede; not the farthest but at least midway
    3. They may start doing something like blowing up dozens of stars or coating them in dyson spheres, even a billions years away we will notice that (the fact we cant seem to see that now is either another mystery of the paradox or we lack the technology or equipment to look that far away)
    4. Possoible wormholes (long shot but maybe not impossible)
    5. It may turn out that the increasing rate of expansion of the universe isnt as fast, or may turn around in the distant future or, long shot, a hyper race may be able to do something about it

    Generally speaking we might not have a chance of getting to the edge of the universe and realistically might not even get close but aliens from many distant galaxies have a good shot of being able to contact us increasing the base numbers of the fermi paradox by millions if not billions of galaxies

  • 0:25 magnemite

  • Being completely alone is actually terrifying and kinda proves god if you think about it?

  • Das für ein deutschen youtuber

  • Did Kurzgesagt really just assume there are only 40 million grains of sand on Earth? (1:13)

  • 💚💚💚👎👎😅😅😅😅🛋

  • School in the future: Hey! Where are you from?
    I'm from mercury! Im guessing you're from pluto

  • Maybe there tons of intelligent life and the just dont like us. I'm one of us and legit I cant stand us……..

  • its obvious. Its the prime directive. Aliens won't contact us until we are able to contact them

  • Lol Magnemite alien

  • One thing I have always wondered is why scientist limit looking for life on habitable planets. Is it guaranteed that just because we couldn't live on an unearth-like planet no life can't? Are we certain that our definition of life is the only definition there is? Perhaps there exists life out there that doesn't need water or anything of things that we need.

  • sidonia spaceship reference!

  • what if we're the most advanced so far?

  • I thought it is better give it the World if give it some holes 🙄

  • 0:22 A little Don’t Hug Me I’m Scared reference

  • i believe the great filter is behind us because allready we have technology to move to different planets and live there. but its expensive so thats why we arent doing it. but if necessary we would be able to do so. We could be the leading race on the galaxy at the moment and we could become like gods to other races. maybe we have gotten lucky and no meteorites have destroyed our planet or something like that.

  • our civilization could one day live on so many other planets that humans on those planets would look different. and hundreds of races would have started with us humans.

  • Motivating rather than scary

  • Watch this when your high

  • So we're the 'not like other girls' part of the universe huh

  • Uh… the Annunaki?

  • curiosity killed the humans 🙂

  • 0:25 top right is Zogg from Betelgeuse!
    The reason we haven't found any aliens is because "Squids are stupid" and we are outside the galactic bureaucracy, thus they haven't send a planetary bio-administrator of class 14 or higher yet.

  • Meanwhile on planet Skixetiza (just made that up lol):
    “Human Paradox: Where are all the humans?”

  • I don’t know, but, you say living things so, bacteria of some type is on other planets, so there is other living things off the earth

  • Galactaaduck is a dick.

  • Ol' one eye

  • I had posted this earlier

    I had asked them..


    They did reply…..



  • 00:02 is that galactus over there???

  • Realizing that ''exist'' it's just a term we invented to things we can see, touch, hear, smell, detect, taste, etc just to prove we are alone or not, but what if there are things in this whole universe that overpass the term ''exist''? That are more than just a ''living'' being with intelligence, this is just awesome

  • Another obvious one which I think is probably true: Space is just too big, we are too remote, and communication too difficult or impossible. Perhaps it is not really possible to reach type 3. It seems to me that filters will be at different places depending on the type of development. For some planets, they might have nuked each other into oblivion. For others, perhaps an interplanetary war might have exterminated them. For others, an asteroid collision might have done it. Remember in our history, there have been mass extinctions that almost lead to the complete annihilation of all life on Earth. So it is quite possible.

  • 5:18
    execuse me
    we recieve messages but we are unable to decode them!
    recently chinas giant radio telescope recieved timed radio waves,
    besides that a martian lander also discovered the same thing.
    possibly ,may or may not :
    * aliens exist *
    ** trying to find other aliens **

  • Greed is the main reason for our suffering. Bad greed that is.

  • Amoooo este canal!!! Gracias YouTube.

  • Or mayby this is 3 level civilation but they are ant-size civilization and we can't see them because they are too small

  • Didn't know Pokemon was just based on a foreign planet 🤷‍♂️ 0:27

  • Hey the aliens in the thumbnail look like…ahh, well, never mind.

  • Type 3 civilizations = the reapers from MASS EFFECT

  • What if all the stuff we leave behind gets found one day by another civilization?

  • if we colonize the milky way in 2 million years, we still have 1 billion years left

  • I seen the Sidonia reference.

  • …and the universe uttered:
    let there be the "arrogantly-stupid" so that the "humbly-sensible" can cherish their awareness
    …and as a result the politicians were borne out of… stupidity arrogance.

  • I think I've figured out what the Great Filter is for us…

    Flat Earthers

  • 4:52 getting mass effect vibes..

  • If were alone then does that mean we are collectable?

  • 0:24 A planet full of magnemites and Zora's?

  • What if the universe if a simulation, or like on giant computer program. The superclusters are information, inside are galaxies and within those are stars that each hold varied amounts of information. Black holes are viruses, created from the destruction of that information.

  • 1:01 is that a sodina reference?

  • If aliens existed, and knew about other aliens why would they contact beings like us? We havent even figured out whats on the bottom of our oceans or if aliens even exist. We are not that big of a civilization yet and is currently being killed by ourselves in the form of global warming. Why us, when there possibly are other more important civilizations to contact.

  • Don’t think I didn’t notice the DHMIS Computer

  • 1:00 Is that Sidonia?

  • I like how Merman from the t.v. series He-Man made an appearance. Also, a ship from the game Master of Orion, the original Sid Meier game, also made an appearance.

  • This is completely illogical. Because the moment we do meet alien life the equation gets flipped because that means that they made it through their filter so the whole equation has to be rewritten, in fact this is junk science. Debunked.

  • That last part was very human of you.
    Good job.

  • 5:01 The Doctor : HOW??!! I'VE DEFEATED YOU TIME AFTER TIME!!!

  • What if aliens are aware of our existence but choose not to visit cause of the dumb things we do?

  • So allah is type 3

  • The Large Hadron Collider the search for the god particle they find it a press the button and then all life is wiped out the final filter

  • Towards the end of the video rant about 5 minutes 25 seconds it gets really bleak lol

  • I personally think there are alians out there like us but we are just so far apart say like millions of light years that we just haven't come in range yet like or they are out there but they just don't think it's time to show them selfs to us yet

  • They are all in Area 51

  • maybe that there could be a barier that divide all different kinds of lifeform.

  • but aliens cant invent wifi lol

  • Did gactuaduck eat us

  • “The universe is too beautiful not to be experienced by someone.”

  • A doomsday machine you say? The last words uttered by a human will be: Watch this!

  • We just not gonna talk about the Magnemite in the video?

  • "We would have noticed by now". Which we already have. Problem is that people refuse to believe in things despite the overwhelming evidence. They are just like flat earthers.

  • Mungkin kita bener" mahluk hidup sendirian di bumi

  • “The Milky Way … consists of up to 400 billion stars … roughly 10 thousand for every grain of sand on earth”

    I think that figure was supposed to refer to the number of stars in the Universe

  • the real answer we actuality don't know if life in universe even exist

  • my only desire remains is to know that there are other sentient life forms around the galaxy..

  • 4:52 are u talking about reapers?

  • "If even one of these planets had developed into a space faring civilisation, we would have noticed by now…" BASED ON WHAT EXACTLY?? The furtherest reach of our radio signals, barely extends over a 100 light years and our galaxy is over a THOUSAND times that size. Based on that, and the fact we don't know what kind of interstellar communications would be used across such massive distances, how can we possibly say we should have noticed other civilisations, when we've barely been looking, ourselves!

  • 4:48 monnolith?

  • I don't agree with the last message… to me, consciousness seems like it's just a chain reaction process. This means that the only reason we think what we call "life" might be the most important thing in the universe, is the fact that we are life ourselves. We link in with consciousness, and its particularity is that it is "aware" of itself.
    This means we see life as the only way to "see" and "appreciate" the universe, only because we are a part of the life ourselves.

    But as you said later in "The egg", there just might be a form of "consciousness" we have yet to see, and because we don't know anything about it, it means there are infinite possibilities of new forms of life we couldn't even think of if we tried, and to an infinite number, the number of what we know is nothing.

    Conclusion : other forms of life exist in the universe, but there is no chance that we could ever discover it if we don't become omniscient before we disappear.
    We'll mathematically just let it slide without even realizing it exists.

  • Sidonia no kishi reference

  • Scariest fact about dimensions is that
    there is a dimension our planet dies in 1000000000000000000000… ways

  • Kurzgesagt – In a Nutshell 0:27 it's a magnemite wow Pokemon exists ?!!!?!?!???!?!!!!

  • Chances are there is life on other planets, but not the type of life most people think of when they think of aliens.

  • 5:25 I'm pretty we're at the center of the visible universe due to the fact we can only as far back as to the light coming off at the big bang, and it doesn't matter if we're in the real center(is there?) of the universe, we can only ever evenly see the red fiery boomness all around us.
    or something like that.

  • I find unreasonable that we don't think about the possibility that we're just not capable of percieving advanced life forms. It has been proven lately that animals are conscious, but their counsciousness is less complex than ours. So… how would an ant percieve us? An ant wouldn't think: "oh, look at that advanced life form", it would just get alarmed by feeling our footsteps, it would only percieve a threat. So what if alien life forms, once they become level three civilizations, don't depend in physical forms? (or at least not our level of physicallity). Is it so difficult to believe that life can occur in more ways than we're able to concieve. I think we're being super naive and anthropocentric.

  • 10,000 stars in our galaxy for every grain of sand on Earth? Um, I feel like that number is probably flipped. Did he mean in the whole universe?

  • You said that Milky Way contains up to 400,000,000,000 stars. You also said that it's approximately 10,000 stars for each grain of sand on Earth. Are you saying that there are only 40,000,000 grains of sand on Earth? There are approximately (and this is a very rough approximation) seven quintillion grains of sand on Earth.

Leave a Reply

Your email address will not be published. Required fields are marked *