NORMAN — The brilliance of Albert Einstein’s theory of special relativity is considered by many to be timeless. University of Kansas professor Bruce Twarog explained how, in layman’s terms, during a presentation Thursday at the Sam Noble Oklahoma Museum of Natural History. A standing-room-only crowd filled an auditorium in the University of Oklahoma museum to hear Twarog and watch his spirited demonstrations. The theory says laws of physics remain the same whether an object is moving or is still, and that the speed of light is constant. That means time and length are not constants. They can differ between people moving at vastly different speeds through effects called length contraction and time dilation. "Please understand how bizarre this is,” Twarog said of Einstein’s discovery back in 1905. Twarog had two pairs of volunteers tossing balls to each other to explain the phenomenon. As one pair tossed a ball to each other while stationary, the other was supposedly doing the same while moving on a train. The professor measured the pairs’ tossing distances and the second one had the longer distance because, from the outside looking in, they were throwing diagonally as a result of moving with the train’s speed. Yet the pair inside the train would dispute that because they stood in front of each other the whole time. "So which one is right? They both are,” Twarog said. "Instead of there being no absolute space (as previously believed), Einstein is saying there is no absolute time.” Some in the audience seemed more intrigued with dark energy and dark space, which came up later during a question-and-answer period. Twarog said physicists believe the universe is expanding more quickly than it did 8 billion years ago because the dark energy is becoming increasingly stronger than the opposing, gravity-like force. "What would cause that?” a woman asked. "I don’t know; that is the whole question,” Twarog said. Twarog’s visit — and the telescopes aimed at Saturn and the moon afterward — were part of OU’s yearlong celebration of the International Year of Astronomy, so declared because 2009 marks the 400th anniversary of Galileo’s use of the telescope. The OU Department of Physics and Astronomy and a team of co-sponsors are presenting a public astronomy program each month. For more information, go to nhn.ou.edu/iya09.