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There are probably 10,000 stars for every grain of sand on Earth, in the observable universe.

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We know that there are maybe trillions of planets.

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So where are all the aliens?

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This is the Fermi Paradox

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If you want to know more about it, watch part one.

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Here we look to the possible solutions to the Fermi Paradox.

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So will we be destroyed or does a glorious future await us?

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Space travel is hard. Although possible, it's an enormous challenge to travel to other stars.

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Massive amounts of materials have to be put into orbit and assembled.

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A journey of maybe thousands of years needs to be survived by population big enough to start from a scratch.

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And the planet might be not as hospitable as it seems from afar.

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It was already extremely hard to set up a spaceship that could survive the trip.

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And interstellar invasion might be impossible to pull off.

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Also consider time, the universe is very old.

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On Earth there's been life for at least 3.6 billion years.

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Intelligent human life for about 250,000 years.

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But only for about a century have we had the technology to communicate over great distances.

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There might have been grand alien empires that stretched across thousands of systems and existed for millions of years,

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and we might just have missed them.

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There might be grandiose ruins washing away on distant worlds.

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99% of all species on Earth have died out.

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It's easy to argue that this will be our fate sooner or later.

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Intelligent life may develop, spread over a few systems and die off over and over again.

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But galactic civilizations might never meet.

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So maybe it's a unifying experience for life in the universe to look at the stars and wonder "Where is everyone?"

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But there is no reason to assume aliens are like us

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or that our logic applies to them

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It might just be that our means of communications are extremely primitive and outdated.

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Imagine sitting in a house with a Morse code transmitter, you keep sending messages but no people answer

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and you would feel pretty lonely, maybe we're still undetectable for intelligent species

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and we'll remain so until we learn to communicate properly.

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And even if we met aliens we might be too different to be able to communicate with them in a meaningful way.

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Imagine the smartest squirrel you can,

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no matter how hard you try, you won't be able to explain our society to it

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After all from the squirrel's perspective a tree is all that sophisticated intelligence like itself needs to survive.

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So she learns cutting down whole forest is madness but we don't destroy forest because we hate squirrels.

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We just want the resources

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The squirrel's wishes and the squirrel's survival are no concern to us.

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A type three civilization in need of resources might threat us in a similar way.

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They might just evaporate our oceans to make collecting whatever they need easier.

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One of the aliens might think for second "Ughh tiny little aches, they built really cute concrete structures, oh well now they're dead."

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before activating warp speed.

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But if there is a civilization out there that wants to eliminate other species,

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it far more likely that it will be motivated by culture rather than by economics.

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And anyway it will be more effective to automate the process by constructing the perfect weapon,

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a self replicating space probes made from nano-machines.

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They operate on molecular level incredibly fast and deadly,

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with the power to attack and dismantle anything in an instant.

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You only need to give them four instructions.

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One, find planet with life.

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Two, disassemble everything on this planet into its component parts.

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Three, use the resources to build new space probes.

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Four, repeat.

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A doomsday machine like this could render a galaxy sterile in a few million years,

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but why would you flight light years to get the resources or commit genocide.

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The speed of light is actually not very fast.

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If someone could travel at the speed of light, it will still take 100,000 years to cross the milky way once

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and you'll probably travel way slower.

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There might be way more enjoyable things than destroying civilizations and building empires.

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An interesting concept is the Matrioshka Brain.

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A mega-structure surrounding a star,

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a computer of such computing power that an entire species could upload their consciousness and exist in a simulated universe.

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Potentially, one could experience an eternity of pure ecstasies without ever being bored or sad, a perfect life.

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If built around the red dwarfs, this computer could be powered for about ten trillions years.

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Who would want to conquer the galaxy or make contact with other life forms if this were an option.

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All these solutions to the Fermi Paradox have one problem.

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We don't know where the borders of technology are.

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We could be close to the limit or nowhere near it.

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And super technology awaits us,

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granting us immortality, transporting us to other galaxies, elevating us to the level of gods.

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One thing we do have to acknowledge is that we really don't know anything.

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Humans have spent more than ninety percent of their existence as hunters-gatherers.

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500 years ago we thought we were the center of the universe.

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200 years ago we stopped using human labors as the main source of the energy.

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30 years ago we had apocalyptic weapons pointed at each other because of political disagreement.

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In the galactic time scale we are embryos,

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we've come far but still have a long way to go.

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The mindset that we really are the center of the universe is still strong in humans,

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so it's easy to make arrogant assumptions about life in the universe.

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But in the end, there's only one way to find out right?

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Hey everybody, we finally have our own subreddit.

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Come by for surveys, discussions about future videos, FAQs and stuff like that.

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This video was made possible by your support on Patreon.

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