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sale of our limited edition calendar supports what we do here at kurzgesagt and our
brand new 12,024 calendar is our most spectacular yet. Don't miss out on your chance
to own a special piece of kurzgesagt history. The universe is going to die one day. But how? Well, it turns out, our cosmic fate will
be decided by a fight between two titans. The Two Warriors Deciding the Fate of the Universe Our universe was born 14 billion years ago
in the Big Bang and has been expanding ever since. For some reason, new empty space
is being created out of nothing between galaxies. Space itself is becoming bigger.
Will it go on forever, or will it stop one day? Today we think the universe is at the mercy
of two cosmic demigods fighting for dominance. The first one is all the stuff in the universe: galaxies, gas, dark matter. While they are
very different they just want to do one thing: get together. Matter is attracted by matter,
pulled together by gravity. And gravity also pulls on the universe as a whole, slowing
the expansion that started at the Big Bang. Our second warrior is empty space. While
it seems, well, empty and powerless, empty space has an intrinsic energy. We don’t
really have an idea what this energy is or why it is there. It’s really a placeholder
that fills a blank in our understanding of reality. But it’s got a cool name: dark
energy. Dark energy pushes things apart, a sort of “anti-gravity” that
accelerates the cosmic expansion.
So we have all the matter in the universe, pulling
in, and empty space infused with dark energy, pushing out. Whoever wins will kill the
universe in fun ways. But who will win? It all depends on the mysterious dark energy: Will its strength stay the same – a
common assumption just because it keeps our models simple? Or will it get weaker,
or will it get more powerful over time? 1. Constant Dark Energy – Heat Death If the strength of dark energy stays constant, it
will win the war. Since space is growing, matter is getting more and more diluted, like sugar
in a cup being filled with more and more tea. But as the universe expands, new empty space
is created, which brings more dark energy, which pushes everything apart even
more , which creates more empty space, which makes the universe grow even faster.
A feedback loop that will make the universe expand at an exponential rate. Every 12 billion
years or so it will double in diameter – forever. But while dark energy is winning the war, matter is winning at least one
battle: At short distances, it can keep things together. Local galaxy
bubbles can overcome the push of dark energy. In a few billion years, our local group of
galaxies will merge into a gigantic ball with trillions of stars. It will soon become our last
view of the cosmos. All other galaxies will be pushed away by the expansion. For us, it will look
like the rest of the universe is rushing away, until in a few hundred billion years we won’t
see other galaxies at all. We will be alone, surrounded by a seemingly infinite, dark void. In about 100 trillion years, all the stars of
our supergalaxy will have died out. All gas that could create new stars has been consumed,
and no new gas can come in. The galaxy will be dark and filled with stellar corpses. Over
quadrillions of years, white dwarfs and neutron stars will slowly cool until becoming truly dark
– turning off the last lights of the universe. All structures, big and small,
will slowly dissolve. One by one, all dead stars and planets will leave the
supergalaxy, which slowly dissolves over sextillions of years. Every object will
end up on its own, which means that dark energy takes over again, creating more
and more empty space between everything. Objects will be so far apart that it will
be as if each had a universe for itself. Not much happens anymore, until in a googol
years, all black holes will have evaporated. In the end, entropy and dark energy won’t
stop until their job is finished. Over time spans you might as well call forever, all
remaining structures might even dissolve into single particles that will be pushed away
from each other by an ever growing empty space. Imagine a whole universe – with just a single,
lonely particle traveling through nothingness. This is the final state, the true end. The Big
Freeze, or Heat Death. A completely featureless, cold and eternally expanding universe. Nothing
will ever be able to happen again. Forever. Well that was a bummer! What else could happen? 2. Increasing Dark Energy – Big Rip What if dark energy gets stronger? In
this case empty space won’t just win over matter – it will literally rip it to pieces. In the Big Freeze scenario, matter lost
the war but won some battles. But here matter wins nothing. Dark energy is growing
stronger over time, overcoming the pull of gravity and creating new empty space at smaller
and smaller distances. In this scenario things will escalate quickly – it could start
as early as 20 billion years from now. First, dark energy will create empty space
between individual galaxies. Our galaxy will leave its local cluster and begin to drift alone
in a rapidly inflating and ever darker cosmos. Some billion years later empty space
starts to push between individual stars, dissolving the galaxy. If you live on a
planet in a star system, the night sky will start looking sad and gloomy, as other
stars are pushed too far away to be seen. A few million years after the sky turns dark, dark energy starts to create empty space
inside star systems. Your planet is pushed away from its star and all life in the universe
freezes to death. There is not much time left, as a few months later dark energy is
creating empty space inside solid objects. Stars, neutron stars, planets, asteroids,
everything solid is being ripped into pieces. If you're on a spaceship, you only have a short time
before you are ripped apart. Half an hour later, even atoms are destroyed as new space is
being created so furiously that electrons and nuclei are separated. Now the universe
has just a fraction of a second left. In this final moment, only dying black
holes remain, drained and defeated by dark energy. They are tiny, septillions
of times smaller than an atom – and they explode with the power of a trillion supernovae
in a trillionth of an octillionth of a second. Finally, the very fabric of reality is torn to its
core, obliterating spacetime itself. The Big Rip. Space and time have lost their meanings, making
it impossible to predict what will happen next. Oof. 3. Decreasing Dark Energy – Big Crunch Poor matter. But there is
one scenario where it wins: If the strength of dark energy decreases with
time, and if this reduction is strong enough, the pull of gravity will win and
all the things in existence will move towards each other – unfortunately
making the universe collapse into itself. No one knows when this might begin, but it could be as soon as a few hundred
million years. What will it look like? As the universe begins to contract, over
billions of years, galaxies and galaxy clusters approach each other until they eventually
collide. They are mostly made of empty space, so a collision is like the gentle
merger of two clouds. At any rate, first galaxies and later individual
stars get closer and closer. As the universe goes on collapsing, you might
worry about stars and planets eventually crashing against each other. This will happen, but it’s
not your worst problem. If space itself shrinks, this also concentrates all the radiation emitted
in the past by all the stars, supernovae and quasars that ever existed. Now ‘empty’ space is
filled with radiation, the dark nothing between stars is heating up, making life unpleasant and
then impossible as planets just burn. Slowly at first, then rapidly, space gets as hot as it
was after the Big Bang. Stars are pretty hot, but now the space around them is hotter
–they are literally boiled from the outside. As the universe collapses into
itself, all galaxies and all stars merge into a single ball of hot
plasma – the Big Crunch is complete. From here on there are two possibilities.
Either the universe will collapse completely into a singularity, a point of zero size and
infinite density, without space and time. The way it might have been before the Big
Bang. Or the universe could “bounce back”, restarting the cosmic expansion, creating a
new baby universe. Somewhat poetic really, everything died, but everything
is reborn. But to be clear, we have zero evidence that this has
happened before or will in the future. So What Will Happen? Most scientists think that dark energy will
stay constant, so the likely fate of the universe is Heat Death – eternal cold and utter
boredom. Which seems sad but has a huge upside: In this scenario we get to have the universe for
the longest. It gives us trillions of years to expand, jump from star to star, maybe even
from galaxy to galaxy. We might even find a way to keep consciousness around forever. We
don’t know. So we just have to wait and see, and make the most of the amazing
universe we have right now. Hey you, why don’t you stick
around for a bit longer. We want to tell you about something
that changed kurzgesagt forever. Kurzgesagt started out as a small-scale passion
project. But creating animated science videos that are free for everyone, doesn’t pay the
bills – DAMN YOU reality! In order to make ends meet we had to take on “real jobs” during
the day and create kurzgesagt videos at night. It was tough but our dream of inspiring
people all around the world kept us going. Then in 2016 everything changed.
Kurzgesagt’s founder, Philipp Dettmer had an idea. He wanted to create something
inspiring that would extend beyond the digital YouTube cosmos. Something tangible.
Something that would represent kurzgesagt’s view of the world and our belief in
humanity’s potential for greatness. His idea: the kurzgesagt Human Era Calendar.
It establishes a new year zero to include all people and cultures around the world. This
new year zero, roughly 12,000 years ago, signifies a time when humans first started
working together on a larger scale, laying the foundation for modern society
and eventually our future ahead of us. The first Human Era Calendar was a
huge success, it sold out within a few hours and inspired thousands of birbs
around the globe. Every year since then, we’ve created a new edition of the Human
Era Calendar – each one more spectacular and successful than the last. It has
enabled us to grow our team, improve our video quality and research standards, and
still release our videos for free for everyone. This year’s calendar is extra special.
Join us as we conduct a series of space experiments to see how they would affect the
development of life. What would a creature living near an orange dwarf look like?
Could life still exist after a supernova explosion? And what the hell is this?
Join us in 12,024 and find out. And of course you can also use it to plan
humanity's next steps towards greatness. To celebrate what may be our most
glorious calendar yet, we’ve prepared a few spectacular limited deals for you.
Thank you so much for being a part of our story and for coming together every year to
make all of this possible! See you in 12,024.
