ENCORE Time passes like an arrow, but what if it flew like a boomerang? Scientists are learning how to reverse time’s most relentless march: aging. But before we rewind time, let’s try to define it, because there’s plenty of debate about just what time is – a fundamental component of the universe or a construct of our consciousness? Find out why, even though pondering the future may cause heartburn, mental time travel has an evolutionary survival advantage. Plus, your brain as a clock; why “brain age” may be more accurate than chronological age in determining lifespan. And while a million-dollar monetary prize hopes to inspire researchers to crack the aging code, one group claims they already have. By reprogramming special genes, they’ve reversed the biological clocks in mice. Find out when human trials begin.  Guests: Dean Buonomano– Neurobiologist and psychologist at UCLA and author of “Your Brain is a Time Machine” James Cole– Postdoc studying neuroanatomy, Imperial College London  Joon Yun– Radiologist, head of Palo Alto Investors and creator and sponsor of the Palo Alto Longevity prize Pradeep Reddy– Research Scientist at the Salk Institute in La Jolla, California Learn more about your ad choices. Visit megaphone.fm/adchoices