When considering the spread of post-biological intelligence we should also spend some time thinking about what the substrate on which it exists would look like.

When considering the spread of post-biological intelligence we should also spend some time thinking about what the substrate on which it exists would look like. Even just working out a likely size for such a substrate would be informative. It might turn out that we are looking for relatively small objects in orbit around stars. Would we even stand a chance of finding a single such object? Could there be one orbiting the Sun? If so, there could be an alien civilization with trillions of individuals existing in our solar system. We'd have little chance of contacting them unless they decided to speak to us or we managed to accidentally identify them through a telescope.