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 add free, plus hours of bonus content,

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

It's great to occasionally get away from it all, but what if some people really, really, really needed to get completely away from absolutely all?

Yeah. So a pair of conversations that have come up on our show often are how you hide spaceships or civilizations and how civilizations would look if they were principally fleet-based.

We explored both in detail in our episodes nomadic

space-based fleets and the Fermi paradox hidden civilizations, but we never really discussed

this combined notion, a civilization on the run trying to stay quiet and escape pursuit.

This is much akin to what we see from the Battlestar Galactica franchise, original or reboot,

and the Corens from Mass Effect, but I wanted to bring some more realism into the concept.

That's where we get our title for today, escaping the galaxy, because as we'll see as we examine

the issue, that almost has to be your long-term solution.

It's also a good excuse for us to discuss the logistics

of launching across the inter-collactic void, with no intent of returning but surviving to arrive

elsewhere. As usual, we'll stick to inside known science for today's discussion, which means

no FTR or magic cloaking drives. The former release least is not a disadvantage for flight either.

After all, if someone kicked your butt so decisively you're willing to flee for centuries

at a minimum, odds are they have the same or better technology as you, especially when you're

in flight and not really a position to be building lots of labs and research facilities.

Outside of science fiction, while stress and necessity can

often lead to breakthroughs and innovation, very little new science gets done during chaos

...