Ever since astronomers reached a consensus in the 1980s that
most of the mass in the universe is invisible — that “dark matter”
must glue galaxies together and gravitationally sculpt the cosmos
as a whole — experimentalists have hunted for the...
For 80 years, scientists have puzzled over the way galaxies and
other cosmic structures appear to gravitate toward something they
cannot see. This hypothetical “dark matter” seems to outweigh all
visible matter by a startling ratio of five to one...
