Science can explain why some people love the heart-pounding, chest- tightening, jumping-out-of-your-seat feeling of a good scare. It’s an evolutionary core emotion that causes us to react when we sense danger, real or perceived. While we can’t always control what scares us, Halloween offers opportunities to make a choice to expose ourselves to those things. That sense of control, choosing to do something scary, is what can make fear fun, said Margee Kerr, a sociologist and author of the book “Scream: Chilling Adventures in the Science of Fear.” “As soon as you take that away,” she said, “it’s …