Ask the Experts--Physics and Math

p>Scientific American's "Ask the Experts" column has been answering reader questions for nearly two decades. Now, we've combed through our archives and compiled some of the most interesting entries into a series of eBooks organized by subject. In the first of the series Physics and Math professors and researchers tackle a wide range of natural phenomena and mathematical concepts from what is antimatter to applications of game theory to what we know about tachyons.