Hello, SFIA audio listeners. In this month's Nebula exclusive, big alien theory,

we're asking the reason alien civilizations might be rare is because most aliens are huge.

To hear it and every episode early and ad-free, plus hours of bonus content,

check out go.nebola.tv slash Isaac Arthur and use my code, Isaac Arthur.

To reach out to the stars and send spaceships across the interstellar void is a titanic task,

but so is setting up an entirely new ecosystem and civilization on the other side.

What happens if those fragile oasises fail to take root and prosper?

Yeah. if those fragile oasis fail to take root and prosper. The Fermi paradox is the big question about why the universe appears to contain billions and billions

of planets, many vastly older than our own pale blue dart, and yet seems to be absent

any huge and ancient

galactic empires. They would also be loud aliens, the kind that make a big splash

on the galactic stage, and their noise would last for a while, maybe thousands of years

or potentially even more, so they would be hard for observers like ourselves to miss. If our future is out among the stars, then surely it was for others who came before us too,

and so we ask, where are they all all?

Today we'll be discussing a new possible explanation, pan-cosmorial theory in conjunction

with Procolation Theory and the Aurora Effect, as a possible

new late filter of the Fermi paradox, to ask if maybe it's simply too difficult to find or

create environments away from Earth on which civilizations can thrive in the long term,

beginning with creating ecologies that could survive deep space missions to new solar systems.

Pancas Morio, meaning all-world limit, is a new concept and makes a strong case for the difficulty

of colonization, though in many ways it is an old argument too, indeed arguably the original

argument that solves the Fermi paradox.

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