From left: Chuma Gault and Jason Delane in "Hymn" at Odyssey Theatre (Photo by Cooper Bates) One of the great powers of theatre is that it can evoke entire worlds and lives on a simple wooden stage, and with only a couple of immersed actors. Such is the case with “Hymn” at the Odyssey Theatre, co-produced with Lower Depth Theatre and written by Lolita Chakrabarti — who also adapted the novel “Life of Pi” for the stage — portraying two English brothers forever changed after fi