Hart–Tipler, Kipping, and the Rare-Intelligence Resolution to the Fermi Paradox: A Cosmological Perspective on Intergalactic Probes
To the point
David Kipping’s three-parameter model shows that if intelligent life can spontaneously arise at rate λ, spread at rate u, and start at time t, then self-replicating probes could colonize galaxies well before now, implying we should have observed them unless such civilizations are extraordinarily rare or blocked by a strong filter.
