Maybe the only cosmic infrastructure required would be listening stations and the ability to steer big rocks to sources? The listening stations would be hard to

Maybe the only cosmic infrastructure required would be listening stations and the ability to steer big rocks to sources? The listening stations would be hard to pick out. They could run a 'reverse' fermi equation of sorts and figure out how fast you need to detect and extinguish signals to keep the universe clear. Would the extermination look anything more than unfortunate random collisions? Do we actually have enough data to calculate if collisions are above some noise floor of random happenstances?