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Some of the brightest minds currently working in the field of cosmology discuss the two most important questions about time: What is it? and, If time can be seen as a kind of ´arrow´, then why do the cosmic and thermodynamic ´arrows´ of time agree?

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The concept of time has fascinated humanity throughout recorded history, and it remains one of the biggest mysteries in science and philosophy. Time is clearly one of the fundamental building blocks of the universe and thus a deeper understanding of nature at a fundamental level also demands a comprehension of time. Furthermore, the origins of the universe are closely intertwined with the puzzle of time: Did time emerge at the Big Bang? Why does the arrow of time ´conspire´ with the order of the initial state of the universe?

This book addresses many of the most important questions about time: What is time, and is it fundamental or emergent? Why is there such an arrow of time, closely related to the initial state of the universe, and why do the cosmic, thermodynamic and other arrows agree? These issues are discussed here by leading experts, and each offers a new perspective on the debate. Their contributions delve into the most difficult research topic in physics, also describing the latest cutting edge research on the subject. The book also offers readers a comparison between the different outlooks of philosophy, physics and cosmology on the puzzle of time.

This volume is intended to be useful for research purposes, but most chapters are also accessible to a more general audience of scientifically educated readers looking for deeper insights.

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Introduction.- Time after Time; R. Vaas.- Fundamental Loss of Quantum Coherence from Quantum Gravity; R. Gambini et al.- The Clock Ambiguity: Implications and New Developments; A. Albrecht, A. Iglesias.- Holographic Cosmology and the Arrow of Time; T. Banks.- The Emergent Nature of Time and the Complex Numbers in Quantum Cosmology; G.W. Gibbons.- The Phantom Bounce: A New Proposal for an Oscillating Cosmology; K. Freese et al.- Notes on Time´s Enigma; L. Mersini-Houghton.- A Momentous Arrow of Time; M. Bojowald.- Can the Arrow of Time be understood from Quantum Cosmology?; C. Kiefer.- Open Questions regarding the Arrow of Time; H.D. Zeh.

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From the reviews:
"This excellent book presents several papers discussing the question of arrow of time from physics and philosophical point of view. If you are a philosopher or physicist I strongly recommend this book for you. ... all papers are very accessible and captivate the reader´s attention at first look. So I promise you that you will get passionate about questions of time when you check this book. It is a really a masterpiece!" (Philosophy, Religion and Science Book Reviews, bookinspections.wordpress.com, December, 2013)

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