Why Does the World Exist?
An Existential Detective Story
Liveright: 310 pp., $27.95
"How old is the Universe?" Kurt Vonnegut asked in his 1973 novel "Breakfast of Champions." "It is one half-second old, but that half-second has lasted one quintillion years so far. Who created it? Nobody created it. It has always been here."
For all its breeziness, that still seems to me a pretty good cosmology, one that expresses the essential intractability of everything. And yet, if Jim Holt's deft and consuming "Why Does the World Exist?: An Existential Detective Story" has anything to tell us,...