Into the Unknown: The Quest to Understand the Mysteries of the Cosmos

In this mind-bending inquiry, Johnson (Constellations for Kids), an astronomy professor at the University of Virginia, investigates unanswered questions about the universe. Surveying theories of “what caused the Big Bang,” Johnson explains that some scientists have proposed our universe was “created inside of a supermassive black hole formed in a parent universe,” while others, following the precepts of string theory, suggest our universe may have arisen from the collision of other universes suspended in a higher dimension. The difficulty of proving such theories means scientists must often settle for ruling out alternatives, Johnson writes, explaining that physicists no longer think neutrinos or black holes could constitute dark matter because calculations have revealed neither are abundant enough to account for dark matter’s gravitational effects. (The most likely culprits include hypothetical particles of gravitational energy capable of moving between dimensions.) Elsewhere, she discusses how debates over whether the laws of nature “could not have been otherwise” raise thorny metaphysical questions about free will. Heady ideas jump off nearly every page, and Johnson has a talent for describing them in breezy, conversational prose. This is perfect for anyone who enjoyed Astrophysics for People in a Hurry. (Oct.)