[shadowgovt]

Oh, I'm not going to care about visitable volume.

With 5 gigayears to work with I'm going to move a few star systems over, break down all the matter orbiting the star into a Dyson sphere made of computronium, and simulate visiting any world I could possibly ever want to.

[qingcharles]

This is one reason to assume we'll never meet any aliens. They're just simulating whatever all day long in their Dyson Goonspheres.