Reading the "endgame" section, and I feel that some serious thought ahould be given to what the replicator colony will do after it has finished dismantling Mercury.
> The shell is not merely a strength structure; it is a fixed logistics skeleton. Its purpose is to provide: dense distributed launch/capture corridors large-scale routing geometry attachment points for high-temperature radiator fields buffering volume for material and coolant traffic alignment and vibration-control structure for the mature transport system...
Pretty sure the idea predates that lecture, it appears in Charles Stross' novel Accelerando from 2005 (which is based on short stories that were published years earlier).
> The mirror fleet does not increase the total power available to the project; Mercury still intercepts only a fixed amount of sunlight.
I think I must be missing something important, because this doesn't make sense to me. If you put your mirrors in orbits where they don't block the dayside surface (sun-synchronous?), then they increase the total surface area receiving solar radiation.
Yeah, orbital mirrors essentially expand the radius of Mercury, increasing the sunlight available. Terrestrial mirrors would ensure that light makes it from the sunward side to the dark side of the planet.
Why does being so deep in the gravity well pose an issue? If you are assuming the Dyson swarm is intended to go back up the well then sure, but that isn't necessary.
Could you elaborate? Why would being deep in the gravity well be a non-starter? I thought Mercury's proximity to Sol was a huge advantage because of the ample solar power which would make planet-side manufacturing easier.
I encourage Dyson sphere enthusiasts to listen to the interesting argument that Dyson spheres they may be deliberately designed as an "sounds neat but is impossible" filter joke, ref: https://www.youtube.com/watch?v=fLzEX1TPBFM .
Sped through that, couldn't stomach the whole thing. Is there more to it than "argument by sneering dismissal"? (Basically, so far as I can tell, her point seems to be "this was intended as a joke to see if you're stupid, so if you believe it, you are, neener-neener!")
I guess it might. I wouldn't plan on it without a very detailed survey though, to say the least. Whereas solar is definitely right there. (And you still have to worry about cooling either way.)
There are other substances that can be used for reactor coolant. Molten salt reactors are actually substantially more efficient than water-cooled reactors because they have a higher operating temperature. You can also use liquid metal as coolant, such as lead or bismuth.