Schwartz (The Living Energy Universe), director of the Human Energy Systems Laboratory at the University of Arizona, proposes "working with a group of top mediums who have consistently received messages, supposedly from the dead," to investigate whether or not there is indeed life after death. Armed with consummate authority (e.g., logic, scientific research and the focus of a recent HBO documentary), the book progresses through the lab's findings. Of particular fun are the session transcripts, which include running commentary provided by lead investigators. (One sitter describes a medium's performance as "dead on.") That their data will convince readers, the authors believe, is a foregone conclusion: "[E]ven skeptics will begin to evolve as a result of these findings." Yet the story comes off like high-grade magic or a splendid infomercial. Despite the reliance on experts (such as magicians, scientists and videographers), the narrative has the suspect tone of a sideshow barker. All the same, Schwartz embraces an admirable passion for curious knowledge and adamantly resolves to uphold his survival-of-consciousness hypothesis until research proves otherwise. (Mar.)