- It is proposed that cold dark matter is condensed into a liquid or solid after sufficient adiabatic expansion. If it constitutes present-day dark matter, the rupture that results from overextension of the dark matter can cause large-scale structure. Luminous matter could sit in nonspherical potentials and experience flattening without rotating. Nonspherical dark matter distributions could possibly be revealed via weak lensing by galactic halos. © 1996. The American Astronomical Society. All rights reserved.