Professor and author Elizabeth Alexander is hosting a book signing for her memoir, “The Light of the World,” at Barnes and Noble, Union Square, Thursday, April 23 at 7 p.m.

Alexander is participating in the “In Conversation With Walter Mosley” event at B&N.

The “Light of the World” reflects on Alexander’s married life, grappling with the subsequent void after the death of her husband and feeling a re-energized devotion to her two teenage sons. Her late husband, artist and chef Ficre Ghebreyesus, passed away in 2012.

A poet, essayist, playwright and teacher, Alexander composed and delivered “Praise Song for the Day” at the inauguration of President Barack Obama in 2009. She has published six books of poems, two collections of essays and a play. Her book of poems, “American Sublime” (2005), was one of three finalists for the Pulitzer Prize and was one of the American Library Association’s “Notable Books of the Year.” Alexander is the former chair of the African ‑American Studies Department at Yale University.