Getting Warped

Science exhibits don't often come with a warning sign. But there's one at the entrance to a sprawling, new exhibit on Albert Einstein's life and science at the American Museum of Natural History in New York City. The sign has no words. It's a video screen whose center is dominated by a dark blob. Around the blob yawn strangely bloated, bowed, stretched, and sometimes doubled images of museum visitors. That's how they might appear if light from them were distorted by a black hole—an unimaginably dense package of matter whose existence follows from Einstein's theories (SN: 9/29/01, p. 203: Available to subscribers at Gravity's lens: Finding a dim cluster).