Last night I had a dream. I dreamed of a great bridge that spanned two peaks shaped like the Devil's Tower. The bridge was a single beam-like structure, black in color, but reflective like volcanic glass. It spanned a distance of many miles, and in my dream I thought "There is no substance strong enough to span this distance that would not collapse under its own weight." So I asked myself, "What material would be strong enough to support this span?" The answer came into my head: "Pre-stressed carbon nanotubes in a diamond matrix." What I am asking all you engineers and scientists on Poal (stop laughing -- there may be a handful of you) is this: Is a composite composed of pre-stressed nanotubes in a diamond matrix possible? Would it yield the strength that would allow a beam miles long to span the distance between two mountain peaks? For those who have no idea what I'm talking about, we do much of our construction using pre-stressed concrete. This is concrete that contains steel rods that have been pre-stretched before the concrete is poured around them, then allowed to relax, which puts pressure on the concrete, holding it together. Pre-stressed concrete beams are much stronger than common comcrete beams would be and can support much greater loads. I was able to find [this](https://www.intechopen.com/books/diamond-and-carbon-composites-and-nanocomposites/carbon-nanotube-cnt-reinforced-metal-matrix-bulk-composites-manufacturing-and-evaluation) on carbon nanotube reinforcement of composits, but there was nothing in this chapter about a diamond matrix. Is it possible? Would it greatly increase the load-bearing strength of a beam made from it?