Dark Matter and the Dinosaurs: The Astounding Interconnectedness of the Universe

by Lisa Randall

Even in an expanding universe, stars or planets or anything else that is sufficiently tightly bound by other forces or by stronger gravitational effects won’t experience the expansion that drives galaxies apart from each other.

Toward the end of the decade, Hubble made his even more famous discovery—the redshift of galaxies—the shift in frequency of light that told scientists the Universe was expanding.

“All science is either physics or stamp collecting.” Though arrogant and a tad obnoxious, this statement does contain a kernel of truth. Science isn’t solely about listing phenomena, no matter how beautiful and remarkable they might be. It is about trying to understand them.

Both casual observers of science and scientists themselves frequently employ Occam’s Razor for guidance when evaluating scientific proposals. This oft-cited principle says that the simplest theory that explains a phenomenon is most likely to be the best one. Its sensible-sounding logic dictates that it is probably a bad idea to build complicated structures when a leaner one will do.