Wiktionary
n. (context science fiction English) programmable matter.
Wikipedia
Computronium is a material hypothesized by Norman Margolus and Tommaso Toffoli of the Massachusetts Institute of Technology to be used as " programmable matter," a substrate for computer modeling of virtually any real object.
It also refers to a theoretical arrangement of matter that is the best possible form of computing device for that amount of matter.
Usage examples of "computronium".
Then we could turn all the available dumb matter into computronium and use it for processing our thoughts.
The latest figures say something like seventy percent of the baryonic mass of the M31 galaxy was in computronium, two-point-nine million years ago, when the photons we're seeing now set out.
Limited bandwidth, not a lot of use to a mature superintelligence that has converted the free mass of its birth solar system into computronium, but sufficient to allow it to hold conversations with its neighbors.
Transcendents don't go traveling because they can't get enough bandwidth – trying to migrate through one of these wormholes would be like trying to download your mind into a fruit fly, if they are what I think they are – and the slower-than-light route is out, too, because they couldn't take enough computronium along.
Sunlight still reaches the birth world, but much of the rest of the star's output has been trapped by the growing concentric shells of computronium built from the wreckage of the innermost planets.
It's computronium, matter optimized at the atomic level to support computing, and they're all running uploads – Dad figured our own solar system could support, uh, about a hundred billion times as many inhabitants as Earth.
Am telling you from beginning, though, turning entire solar system into computronium is real bad idea, long-term.
They look like ordinary human stem cells at a distance, but instead of nuclei they have primitive pinpricks of computronium, blobs of smart matter so small they're as dumb as an ancient Pentium, reading a control tape that is nevertheless better structured than anything Mother Nature evolved.
Traditional optics are long since obsolete – tunable matter can slow photons to a stop, teleport them here to there, play ping-pong with spin and polarization – and besides, the dumb matter in the walls and floor has been replaced by low-power computronium, heat sinks dangling far below the floor of the lily-pad habitat to dispose of the scanty waste photons from reversible computation.
Conscious civilizations sooner or later convert all their available mass into computronium, powered by solar output.
They're armed and dangerous, and if they turn their drive flame on the roof and set fire to the atmosphere in here, we'll be in trouble – it would rupture our lift cells, and even computronium doesn't work too well under a couple of million atmospheres of pressurized metallic hydrogen.
Or maybe steal a Matrioshka brain that's succumbed to senile dementia and turn it back into planetary biomes with cores of diamond-phase computronium to fulfil some kind of demented pastoralist nostalgia trip.