The author of the Kurt Cobain biography "Heavier Than Heaven" examines the legacy of the Nirvana frontman and discusses why he still matters twenty years after his death. On April 5, 1994, 27-year-old Kurt Cobain took his own life. His desperation to kick drugs, his complicated relationship with fame, his tortured soul--all these elements came together in one terrible moment, and the landscapes of music and pop culture were forever changed. Two decades...