Eternal Inflation


Book Description

In this book, I discuss the long-standing technical and conceptual problems arising within the statistical framework describing models of cosmological inflation, known collectively as the "measure problem" in multiverse cosmology. After reviewing various existing approaches and mathematical techniques developed in the past two decades for studying these issues, I describe a new proposal for a measure in the multiverse, called the reheating-volume (RV) measure. The RV measure is based on approximating an infinite multiverse by a family of progressively larger but finite multiverses. I give a detailed description of the new measure and its applications to generic models of eternal inflation of random-walk type and to landscape scenarios. The RV prescription is formulated differently for scenarios with eternal inflation of the random walk type and for landscape scenarios. I derive analytic formulas for RV-regulated probability distributions that is suitable for numerical computations.




Topics in Inflation and Eternal Inflation


Book Description

This thesis is divided to three parts. In Chapter 1 we study observational signatures of chaotic inflation with nonminimal coupling to gravity. In the next two chapters we focus on the eternal nature of inflation and the measure problem. In Chapter 2 we compare predictions of several measures in eternal versus non-eternal inflation. Finally in Chapter 3 we study the Boltzmann brain problem for the scale factor cutoff measure of eternal inflation.




Inflationary Cosmology


Book Description

Some 25 years after the birth of inflationary cosmology, this volume sets out to provide both an authoritative and pedagogical introduction and review of the current state of the field. Readers learn about the arguments supporting the many different scenarios of cosmic inflation. Articles are written by eminent scientists, many of whom have made pioneering contributions to the field of inflationary cosmology.




Particle Physics and Inflationary Cosmology


Book Description

A monograph on inflationary cosmology and cosmological phase transitions, investigating modern cosmology's relationship to elementary particle physics. This work also includes a non-technical discussion of inflationary cosmology for those unfamiliar with the theory.




An Infinity of Worlds


Book Description

What happened before the primordial fire of the Big Bang: a theory about the ultimate origin of the universe. In the beginning was the Big Bang: an unimaginably hot fire almost fourteen billion years ago in which the first elements were forged. The physical theory of the hot nascent universe—the Big Bang—was one of the most consequential developments in twentieth-century science. And yet it leaves many questions unanswered: Why is the universe so big? Why is it so old? What is the origin of structure in the cosmos? In An Infinity of Worlds, physicist Will Kinney explains a more recent theory that may hold the answers to these questions and even explain the ultimate origins of the universe: cosmic inflation, before the primordial fire of the Big Bang. Kinney argues that cosmic inflation is a transformational idea in cosmology, changing our picture of the basic structure of the cosmos and raising unavoidable questions about what we mean by a scientific theory. He explains that inflation is a remarkable unification of inner space and outer space, in which the physics of the very large (the cosmos) meets the physics of the very small (elementary particles and fields), closing in a full circle at the first moment of time. With quantum uncertainty its fundamental feature, this new picture of cosmic origins introduces the possibility that the origin of the universe was of a quantum nature. Kinney considers the consequences of eternal cosmic inflation. Can we come to terms with the possibility that our entire observable universe is one of infinitely many, forever hidden from our view?




String Theory For Dummies


Book Description

A clear, plain-English guide to this complex scientific theory String theory is the hottest topic in physics right now, with books on the subject (pro and con) flying out of the stores. String Theory For Dummies offers an accessible introduction to this highly mathematical "theory of everything," which posits ten or more dimensions in an attempt to explain the basic nature of matter and energy. Written for both students and people interested in science, this guide explains concepts, discusses the string theory's hypotheses and predictions, and presents the math in an approachable manner. It features in-depth examples and an easy-to-understand style so that readers can understand this controversial, cutting-edge theory.




Many Worlds in One


Book Description

A Leading Figure in the Development of the New Cosmology Explains What It All Means Among his peers, Alex Vilenkin is regarded as one of the most imaginative and creative cosmologists of our time. His contributions to our current understanding of the universe include a number of novel ideas, two of which—eternal cosmic inflation and the quantum creation of the universe from nothing—have provided a scientific foundation for the possible existence of multiple universes. With this book—his first for the general reader—Vilenkin joins another select group: the handful of first-rank scientists who are equally adept at explaining their work to nonspecialists. With engaging, well-paced storytelling, a droll sense of humor, and a generous sprinkling of helpful cartoons, he conjures up a bizarre and fascinating new worldview that—to paraphrase Niels Bohr—just might be crazy enough to be true.




The Inflationary Universe


Book Description

This is the compelling, first-hand account of Alan Guth's paradigm-breaking discovery of the origins of the universe—and of his dramatic rise from young researcher to physics superstar. Guth's startling theory—widely regarded as one of the most important contributions to science during the twentieth century—states that the big bang was set into motion by a period of hyper-rapid “inflation,” lasting only a billion-trillion-billionth of a second. The Inflationary Universe is the passionate story of one leading scientist's effort to look behind the cosmic veil and explain how the universe began.




Introduction to Cosmic Inflation and Dark Energy


Book Description

Cosmic inflation and dark energy hold the key to the origin and the eventual fate of the Universe. Despite the increasing prominence of these subjects in research and teaching over the past decade or more, no introductory textbook dedicated to these topics has been previously published. Dr. Konstantinos Dimopoulos is a highly regarded expert in the field, and an experienced communicator of the subject to students. In this book, he provides advanced undergraduate and early graduate students with an accessible introduction and equips them with the tools they need to understand the cosmology of cosmic inflation and dark energy. Features: Provides a concise, pedagogical "crash course" in big bang cosmology, focusing on the dynamics and the history of the Universe, with an emphasis on the role of dark energy Chapters contain questions and problems for readers to test their understanding The first book to make cosmic inflation and dark energy accessible to students




The Nature of Nature


Book Description

The intellectual and cultural battles now raging over theism and atheism, conservatism and secular progressivism, dualism and monism, realism and antirealism, and transcendent reality versus material reality extend even into the scientific disciplines. This stunning new volume captures this titanic clash of worldviews among those who have thought most deeply about the nature of science and of the universe itself. Unmatched in its breadth and scope, The Nature of Nature brings together some of the most influential scientists, scholars, and public intellectuals—including three Nobel laureates—across a wide spectrum of disciplines and schools of thought. Here they grapple with a perennial question that has been made all the more pressing by recent advances in the natural sciences: Is the fundamental explanatory principle of the universe, life, and self-conscious awareness to be found in inanimate matter or immaterial mind? The answers found in this book have profound implications for what it means to do science, what it means to be human, and what the future holds for all of us.