Simmons advocates a careful approach to the subject, covering such topics as the wave equation, Gauss's hypergeometric function, the gamma function and the basic problems of the calculus of variations in an explanatory fashions - ensuring that students fully understand and appreciate the topics.

    Yet recent theories suggest that there is far more to the universe than what our instruments record--in fact, it could be infinite. Colossal flows of galaxies, large empty regions called voids, and other unexplained phenomena offer clues that our own "bubble universe" could be part of a greater realm called the multiverse. How big is the observable universe? What it is made of? What lies beyond it? Was there a time before the Big Bang? Could space have unseen dimensions? In this book, physicist and science writer Paul Halpern explains what we know--and what we hope to soon find out--about our extraordinary cosmos.Explains what we know about the Big Bang, the accelerating universe, dark energy, dark flow, and dark matter to examine some of the theories about the content of the universe and why its edge is getting farther away from us fasterExplores the idea that the observable universe could be a hologram and that everything that happens within it might be written on its edgeWritten by physicist and popular science writer Paul Halpern, whose other books include "Collider: The Search for the World's Smallest Particles," and "What's Science Ever Done For Us: What the Simpsons Can Teach Us About Physics, Robots, Life, and the Universe"

    Because it takes time for light to travel, we see more and more distant regions of the universe as they were in the successively greater past. Impey uses this concept—"look-back time"—to take us on an intergalactic tour that is simultaneously out in space and back in time. Performing a type of cosmic archaeology, Impey brilliantly describes the astronomical clues that scientists have used to solve fascinating mysteries about the origins and development of our universe.The milestones on this journey range from the nearby to the remote: we travel from the Moon, Jupiter, and the black hole at the heart of our galaxy all the way to the first star, the first ray of light, and even the strange, roiling conditions of the infant universe, an intense and volatile environment in which matter was created from pure energy. Impey gives us breathtaking visual descriptions and also explains what each landmark can reveal about the universe and its history. His lucid, wonderfully engaging scientific discussions bring us to the brink of modern cosmology and physics, illuminating such mind-bending concepts as invisible dimensions, timelessness, and multiple universes.A dynamic and unforgettable portrait of the cosmos, How It Began will reward its readers with a deeper understanding of the universe we inhabit as well as a renewed sense of wonder at its beauty and mystery.

    Confident America has been conquered, Satan prepares to initiate the final stage of his master plan, but it requires a willing partner—will she say yes?Convinced his demon general Lord Nefarious has successfully conquered America, Satan himself now decides it’s time for him to step out of the shadows and complete his master plan. But for it to succeed, he must find a willing partner… On the run, frightened, and alone, Rae is cornered one fateful night in a rundown motel room by the devil himself. He has a once-in-eternity offer for her—the chance to change the world forever. But to convince her to freely accept it, Satan needs to connect with Rae’s past, present, and future to prove to her he can be trusted after all. A showdown for the ages is officially on, and humanity hangs in the balance.