Picture sitting at a baseball park, leisurely watching a game. Your mind wanders, torn between a box of Cracker Jack and the conversation drifting down from the row behind you. Suddenly the crack of a bat snaps you to attention, and you scan the field for the ball. Physicist Alan Nathan would say your attention is piqued because well-hit balls make a different noise than weak pop-ups do.
Log in
Subscribers, enter your e-mail address for full access to the Science News archives and digital editions.