From: Henry Baker <hbaker1@pipeline.com> "nuclear" materials made from the basic stuff of neutrons & protons... we used to think that diamonds could only be made under extreme pressure, but this has been found to be false; diamond coatings can be made with with chemical vapor deposition (CVD) under relatively low pressure... What I'm thinking of is a kind of "foam" which is a more-or-less fractal material made out of nuclear "soup" (protons-cum-neutrons). Think Sierpinski pyramids or Apollonian foams. Since the material is mostly empty space, it could be considerably less dense than the stuff of neutron stars. ...could it exist?

--First of all, it could not have net positive charge (some percent protons) and still be a "bulk material." So you'd need electrons in the soup too, or it'd have to be neutrons only. (And you might as well just drop the fig leaf and just say it is made of of quarks.) Now actually a "hot soup" made of neutrons, protons, electrons, positrons, neutrinos, and photons at MeV to GeV temperatures presumably did exist in the early universe, and things would have stayed that way forever if there had not been expansion. But I assume Baker is not satisfied with that stuff, he wants his soup cold. Now if it were just neutrons only, then everybody believes it'd be unstable to beta decay, meaning you lose. Can this instability be proven, or is it merely a good guess? Probably the latter. I don't think anybody currently can *prove* Baker's magic material (should I presume we should call it "dough"?) cannot exist. If it were neutrons, protons, and electrons all mixed, then the protons could stabilize nearby neutrons via their attractive energy, and the electrons could provide overall charge neutrality. However that only works if enough protons are enough nearby each neutron (within about 1 fm). And if you try to make some sort of stringlike or treelike or frothlike filamentary structure with neutrons and protons along the strands, then you probably are going to be unstable due to enormous surface energy (nuclear matter has high surface tension). So... this is not a proof, and probably no proof can be produced with present day mathematics... but... I feel there is good reason to believe "Baker loses" i.e. no such magic material can exist. What however might exist is a so-called "island of stability" consisting of certain nuclei like flerovium-298, unbinilium-304 and unbihexium-310. See http://en.wikipedia.org/wiki/Island_of_stability This is based partly on theoretical understanding of nuclear energies from "shell models" and partly on voodoo, but it might be that certain transuranic elements with the right magic numbers of protons & neutrons might be able to exist with remarkably long half lives. In any case, nobody has been able to synthesize the highest-voodoo isotopes so nobody has been able to find out whether this speculation is true. There are some partial experimental indications that is it true, but the whole question looks out of reach of experiment, nobody has any feasible way to synthesize these beasts. You might think, though, that if it were true, then those beasts would have gotten made, and released into the outside universe, during neutron star collisions. Since nobody has detected these atoms, presumably they all are unstable with halflives always shorter than, say, 50 MYr (since otherwise we would have detected them).