The theory is that there may be civilizations, or remnants (AIs), that have a vested interest in removing possible competition for resources, or in the case of the AIs, have been instructed to snuff out signs of life for the same reason.
If you are the first one and want to make sure to prevent all future advanced civilizations from evolving, you send out von Neumann probes. You can tell them to build relativistic kill missiles and destroy all planets. No planets = no new civs, probably.
yreg|1 year ago
If you are the first one and want to make sure to prevent all future advanced civilizations from evolving, you send out von Neumann probes. You can tell them to build relativistic kill missiles and destroy all planets. No planets = no new civs, probably.
bufferoverflow|1 year ago
You don't know that. Maybe our planet once had some amazing high-energy isotope/mineral that was completely mined out.