Aidan Flax-Clark speaks with author Neel Mukherjee about his new novel, "A State of Freedom" and his evolving notions of home, autonomy, migration, and ghosts. ”A ghost is someone who belonged to a particular world who had an unhappy or tragic or violent ending to that particular life and hasn’t found a resting place in another world,” Mukherjee says, “this could be a very a good working definition for who a migrant is.”