KNOW EINSTEIN.(Albert Einstein exhibit at the American Museum of Natural History, New York, New York)(Biography)

"My dear kitten,'' Albert Einstein wrote, in 1901, to his first wife, the physicist Mileva Maric. "I just read a wonderful paper by Lenard on the generation of cathode rays by ultraviolet light." The romance didn't last. By 1914, Einstein had presented a list of "conditions" under which he could consent to remain in his sour marriage. Among them was a demand to have three meals a day delivered to his room. There was also this: "You are neither to expect intimacy nor to reproach me in any way.''

By then, Einstein was having an affair with his cousin Elsa Lowenthal, who soon became his second wife (and who, it is often said, remained his second wife by permitting him to "meet" with Betty Neumann, the niece of a friend, twice a week for nearly a decade). The divorce from Mileva was bitter, but it generated one of the more unusual legal agreements in the history of science: Einstein assumed that he would eventually win the Nobel Prize, so he instructed his lawyers to make the money part of the divorce settlement.

Visitors to the Einstein exhibit that opened last week at the American Museum of Natural History may be inclined to skip lightly over the panels dedicated to his complicated personal life, but it is strangely comforting to see that the man who created the modern world was so frequently befuddled by it. His relationships often failed. He fled one country and lived uneasily in another. He hated totalitarianism but was opposed to capitalism. He barely knew his sons.

Einstein's thoughts are often portrayed as too complex for mortals to master. That turns out to be untrue. In the exhibit, the curator, Michael Shara, explains how light travels, why time warps, what makes stars shine. Walk in the door and you are immediately greeted with a view of yourself as seen through a black hole. (It is not a pretty sight.) Shara had access to the collection of Einstein's papers at Hebrew University, and he has made exquisite use of them. "Everything you have ever thought about space and time is wrong," he says. "Absolutely wrong." Shara never cheats on the science, but, because many of us are at least a tiny bit afraid of physics, he and the graphics team, led by Stephanie Reyer, have provided a series of interactive aides to penetrate the complexity of Einstein's world. For instance, they present some amusing scenarios ...