How Far Can We Go? Limits of Humanity.

Is there a border we will never cross? Are there places we will never reach,
no matter how hard we try? Turns out there are. Even with science fiction technology,
we are trapped in our pocket of the Universe. How can that be?
And, how far can we go? We live in a quiet arm of the Milky Way;
A spiral galaxy of average size, – about 100,000 light years across – consisting of billions of stars, gas clouds,
dark matter, black holes, neutron stars, and planets, with a supermassive
black hole in the galactic centre.>From afar, our galaxy seems dense, but
in reality, it consists, mostly, of empty space. With our current technology, sending a human
to the closest star, would take thousands of years. So, our galaxy is pretty big. The Milky Way is not alone, though. Along with the Andromeda galaxy,
and more than fifty dwarf galaxies, it’s a part of “The Local Group”; a region of space about ten million light years
in diameter. It is one of the hundreds of galaxy groups in
the “Laniakea Supercluster”, which, itself is only one of millions
of superclusters, that make up the observable universe. Now, let’s assume, for a moment, that
we have a glorious future; humanity becomes a type three civilisation, does not get wiped out by aliens, and develops interstellar travel based on
our current understanding of physics. In this best case scenario,
how far could we possibly go? Well; the local group. It’s the biggest structure that humanity
will ever be a part of. While it’s certainly huge, the local group
accounts for only 0.00000000001 % of the observable universe. Let this number sink in for a moment. We are limited to a hundred billionth of
a percent of the observable universe. The simple fact that there is actually
a limit for us, and that there is so much universe that we will never
be able to touch, is kind of frightening. Why can’t we go further? Well, it all has to do with
the nature of nothing. Nothing, or empty space, isn’t empty
but has energy intrinsic to itself; so-called “quantum fluctuations”. On the smaller scale, there is
constant action, particles and antiparticles appearing and annihilating themselves. You can imagine this quantum vacuum as
a bubbling part: with denser, and less dense regions. Now, let’s go back 13.8 billion years
when the fabric of space consisted of nothing at all. Right after the big bang, in an event known
as cosmic inflation, the observable universe expanded from the size of a marble to
trillions of kilometres, in fractions of a second. This sudden stretching of the universe was
so fast and extreme, that all those quantum fluctuations were
stretched as well, and subatomic distances became
galactic distances, with dense and less dense regions. After inflation, gravity began to pull
everything back together. At the largest scale, the expansion was
too quick and powerful to overcome but in smaller scales,
gravity emerged victorious. So, over time, the denser regions,
or pockets, of the universe, grew into groups of galaxies, like the one
we live in today. Only stuff inside our pocket – The Local Group –
is bound to us gravitationally. But wait, what is the problem then? Why can’t we travel from our pocket,
to the next one? Here, dark energy makes everything complicated. About six billion years ago,
dark energy took over. It’s basically an invisible force or effect,
that causes, and speeds up the expansion of the universe. We don’t know why, or what dark energy is,
but we can observe its effect clearly. In the early universe, there were larger,
cold spots around the local group, that grew into clusters with thousands
of galaxies. We are surrounded by a lot of stuff,
but none of those structures and galaxies outside of the local group are gravitationally
bound to us. So the more the universe expands,
the larger the distance between us and other gravitational pockets becomes. Over time, dark energy will push the rest
of the universe away from us, causing all the other clusters, galaxies, and
groups to eventually become unreachable. The next galaxy group is already millions
of light years away, but all of them are moving away from us,
at speeds we can’t, ever, hope to match. We could leave the local group, and then
fly through intergalactic space, into the darkness, but we would never
arrive anywhere. While we will become more and more stranded,
the local group will become more tightly bound, and merge together to form one giant elliptical galaxy,
with the unoriginal name “Milkdromeda” in a few billion years. But it becomes even more depressing: at some point, the galaxies outside
the local group, will be so far away, that they will be too faint to detect, and the few
photons that do make it to us, will be shifted to such long wavelengths,
that they will be undetectable. Once this happens, no information outside
of the local group will be able to reach us. The universe will recede from view. It will appear to be dark and empty
in all directions, forever. A being born in the far future in
Milkdromeda, will think there is nothing but its own
galaxy in the entire universe. When they look far into empty space, they
will only see more emptiness and darkness; they won’t be able to see the
cosmic background radiation, and they won’t be able to learn about
the Big Bang. They will have no way of knowing
what we know today; the nature of the expanding universe,
where it began, and how it will end. They will think the universe is static and eternal. Milkdromeda will be an island in the darkness,
slowly getting darker and darker. But still, with its trillions of stars,
the local group is certainly large enough for humanity. After all, we still haven’t figured out
how to leave our solar system, and we have billions of years
to explore our galaxy. We have the incredible luck to exist at
the perfect moment in time to see, not only our future but also our
most distant past. As isolated and remote as the local group is,
we can perceive the entire universe, grand and spectacular as it is right now. This video was sponsored by Do you feel isolated in a humongous universe? Why not set up a website or blog
and share your thoughts with other humanoids around you? Squarespace lets you do that
with easy-to-understand tools very quickly and without any knowledge of web design. You can also use the code “NUTSHELL” to save
10 % and support Kurzgesagt in making more videoes about our place
in the universe. Thanks so much for the help with the video
to Ethan Siegel. Follow his astronomy blog here. You can support us directly at Patreon
or get Kurzgesagt merch here. It really helps. It is awesome that you watched this far,
so we have made a playlist for you about more universe stuff. Subtitles made by Sebastian Winkelmann Subtitles by the community

About the author


  1. If the big crunch theory is correct the entire human race will technically be within Planck lengths of anything in the universe

  2. what about if the big bang wasn't what we thought it was, we see it the start of the universe. but what IF the big bang happens all the time but the universe is just that big we don't detect it. like going into a massive cave with a candle, we only see a little part of the cave that our candle light – lights up. but then if we was to switch a light on to light the full cave up we would see that there are millions of people inside doing the same thing with little candles thinking they are the only ones who are in that cave, alone, at the centre of it. so just maybe, we just aren't thinking big enough.

  3. im pretty sure in billions of years we will have managed to modify our bodies so that we can travel with lightspeed and explore em all

  4. Dark energy is a theory to explain something we don't understand. You should not talk about it as though it is indisputable fact.

  5. But what if the actual universe is actually a much bigger one but had expanded so far we cant detect others outside our local group (the now observable universe)? This is depressing

  6. Converging energy could be made by small kinetic energy sources, and venting the energy, with additions of objects to concentrate the energy into manifesting into material forms, but to also create insulative or insulation matter. Insulating the installation, with tech that we already have, but it's risky and rewarding if it works. It may form a soul like material, it's really good, the infinity end game. Except the black widow demise, technically it was not him sacrificing her, no sacrifice, except gamora was made in the movies. Also time travel, not a changeable timeline, however the other stones would have changed that, instabalisation of reality and more. But I have tinkered, and considered twins/natural diverse anomalies of the physiology and physics. But only 3 order, Chaos, and spirit, and 6 or 7 possible suites for the the whole collection of ideas. World and infinity stones. although DC comics have similar references for other natural forces ideas. Death, sandman, and 1 or 2 unknowns. I'm still referencing the potentially natural world, however, it's not likely to work, but maybe. Maybe it already is, who knows. Maybe life, if something like that exists. I watched the movie on YouTube, and I had the rest, except for wasp, black panther and the new ones. But it's better to have timing. Watching it at the right time by shire luck. I kinda like it, and I'm not a collector.

  7. If the kinetic energy stabalises after, maybe it could be beneficial to build it in a remote location, with environmental distractions and distance, for the time it takes the potential soul, body and anything else to potentially form a containerment. As it !ay produce life, and it may find humanity a interesting idea to pursue.

  8. My theory was that energy was orderly and constructive, creating life and a home for life. making good, light, virtue, order and constructional. As a creative physiological orientation, having a more extensive physiology. Reality with the opposite, behaving chaotic and destructive, capitalising on all that exists, perverting and capable of transitioning things from the world, through reality. Creating a kind of natural heaven/for energy and order or light and hell/for reality and chaos or darkness. Soul being orientated to life by self sustaining life, like belief, appearing potentially like a star. But the spirit is orientated to matter, architecturing matter and structure from the whispers of potentially mother nature's indescression of effecting nature minutely.the spirit is spiritually materialistic, creating structure from its materialistic orientation, but soul is materialistically a membrane, but like beleif. Spirits have a defect though, through developing from sinister orientation, it may become very perverted and evil, as a desperate fiend. Many variables exist, leading to evil and other badness, in maybe all, but maybe not. Who knows.

  9. Kurzgesagt probably won't see this but there is still possibility of going to the other groups. We still don't know the exact limits of technology. There might be technology that pops up that we never knew about or dreamed and thought about. I know that this video is just based on what know, understand, and theorized. Also I really love your videos being informational and stuff but I'm just saying we probably don't know what the limits of humanity and what we can do in the universe or multiverse.

  10. So is that why there could have been ancient aliens long ago, but not any now anymore? Every second that goes by. Every instant of time, including the time it took you to read this far into my comment… the universe expanded more. We keep getting further and further away from everything else in the universe. So maybe the more time that goes by, there’s less of a chance we will ever encounter an alien species.

  11. I think that if we become a galactic civilization, it would probably be enough. 100.000 light years of territory sounds good too me. Not that I ain’t more ambitious then that, but the milky way is just a big deal…

  12. so black holes, big bang, dark energy and empty space you say? 😀 I liked your videos from the begining but now you are taking theories and presenting them as facts….you can say that mentioned informations are not validated by scientific experiments and are just few of many theories …

  13. What if our observable universe is a small island of light in an ocean of darkness, much like the local group in the video? Imagine what could be out there.

  14. Heaven and hell, a angel recruits a warlock boy, by bringing him to thr gates of heaven and drops him to hell, where the castle lies. I was 16. Me and somonelse had a competition to see who was a better writer, he sugested and sort of demanded it to be a sdaptation of a person goes on a tour of hell, but it may have also been heaven. I dont play by rules. He could have one, but he chose a judge which saw 2 pages, and after reading it, dae 7 ot 12+, choosing 2 but she seemed to have like it. Later the science teacher read his and liked it, and may have liked his better. Aldo pointing out my rap ing mis spelling, incorect number of p letter and a rude word is spelt. I wrote heaven and hell, based on and potentially in reference to energy and reality who if real are literally family. In a way. School was where I wrote it. College was the cause of my deep thought, something special I didn't get. However it wasn't mine to have and it's right that it wasn't. But my stories clicked on to science, but also supernaturally orientated things, like hell. God was a tyrant to the world in my story, as lucifer broke the seals that bound the cjildren of life. Heaven, hell purgatory, nutrility good, evil, light, darkness, death, life, no longer know. Maybe its purgatory, the soul/spirit, it is virus like, a insane or non insane creature able to insert it's conciousness in of the body and brain. The only issue was the power to take over, but if it was it, everything would be changed to it's specifications and taken control of. Spirits are pychologically and physiologically various. Making it a perfect comparible specimen. And purgatory is wild and disturbing. Cutting of Lucifer's wings, and stitching them back on, eating angels, and jumping from angel to angel, killing them as he did. I was 19+. I listened to my mum back then, and deleted the progress, but I still have the beginning and some more, if it is not the begining. But if it is possible to retrieve such data. It may still exist. Viruses do not necessarily have such nature's.

  15. Matter is a lifeform that could be soul/spirit/essence. Nuetrally natural materialistic format, psychologically, physiologically, literal form. Building spiritual material.

  16. No, we will cross into other universes, or we will create them if they don't currently exist.
    There is no ultimate limit to humanity, given infinite time, I deny the premise.
    Also no proof that the universe will truly die, only conjectures based on projections of poorly understood mechanisms that wont even be noticeable for tens of billions of years.
    The only thing we cannot do is surpass whoever is watching the show of this existence.
    It's measurement of us, like particles, is possibly the only thing we will not understand.

  17. What if there is a multiverse and the rapid expansion got them so far apart that it would seem like there's only one… 🤔

  18. Huh? I don't get these people who get an existencial crisis because of that. It should be the other way around. We live in a time when we're able to see and learn all these things. Aliens/Humans in the future won't be able to see any other galaxy. THAT is really depressing if u ask me. I'm grateful to be born in this time and to be able to witness all these beautiful wonders of the universe. It's like we're a chosen species.

  19. everyone: we'll never reach outside our local group
    –oil discovered outside local group–
    america: sounds like everywhere else needs some freedom

  20. Nah homie, you cant put what we can observe into a number because the universe and what exists as a whole is infinity. No matter how much we explore or how advanced we go there will always be something we dont know and that dosent factor in dimensions and alternate realities along with the weird thing called time. We exists in all points of time at the same time. Weird. And if the universe is infinite then no matter how far we go we searched nothing of the universe

  21. Hear me out – what if there is something we can never know about the origin of our universe because we are too late to see it? We might already be "staring into darkness" but in a different way.

  22. I think of the universe as an atom. That atom has many other atoms around it and keep zooming out its a cell, then it keeps going. That cell makes up another universe. That universe is part of another atom. Reverse it back to us we zoom in far enough its an atom. Zoom in farther its a whole new universe and etc.. kind of makes everything irrelevant because the universe is one consciousness that exists in everything at once so each life is pointless. Weird

  23. Life is a result of coming to be, however any life does create energy and death creates a abnormality of reality, resulting in a new addition of scientific Theory. Energy may even be a factor of the creation of life, as a environmental aberrational energy, stabalising and attempting to control the birth. Indecating it's Representation of life in regards of energy. Reality is hard to understand because death is difficult subject to conquer.

  24. How is possible observable universe is so big? How its possible we can see that far? Its milions of light years. I think it's a one big bulshit and we haven't seen further than our galaxy. Maybe even less.

  25. While sad, it actually makes me slightly happeier that a "big rip" has an alternative where everything just dousnt get seperated.

  26. What about, if instead of super massive black holes at the centre of every large galaxy… they’re in fact wormholes. 🤔

    Fast travel: Enabled

    Sorry dark energy 😐

  27. If we r imagining the limit, it is limitless. The reason is that we cannot know. 30 years ago, the idea that we might be in a matrix Universe was not very present. The creation of computers has opened new concepts. The same goes for the Wright brothers' plane, electricity, every and any invention/discovery is a building block to another building block.

  28. I was hoping for a better answer. Given we rode horses around 100 years ago and now people are actively working on warp drive physics lets assume we can warp spacetime around us and travel faster than light like 9x faster. Then where is the edge. What do we see when we get there? Since time and space began with our universe bang there must be a defined edge where it does some funky loop back around infinite time space border right?

  29. Ι think that our ''pocket'' of galaxies provides much more space, than we can possibly reach, explore and colonize. Much much more.

  30. This is very depressing. We should bloody do something- create wormholes or whatever, because all those galaxies beyond our Local Group- we gotta observe and explore them! How many aliens must be out there!

  31. Maybe once we understand how dark matter works, we can start to influence it or work with it idk and find a way to do things we consider impossible now?

  32. Kinda crazy to think that if no species in our local group had come up with telescopes this early, some crucial information would have never been accessable to the future scientists. Also crazy that all this highly valuable information is stored on tiny chips and hard disks lol

Leave a Reply

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