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What Time Is It?
by the Editors


Section 1: History and Philosophy

1.1   Real Time
        by Gary Stix

1.2   That Mysterious Flow
        by Paul Davies

1.3   A Hole at the Heart of Physics
        by George Musser


Section 2: The Human Side

2.1   Times of our Lives
        by Karen Wright

2.2   Remembering When
        by Antonio Damasio

2.3   Clocking Cultures
        by the Editors


Section 3: Machines and Measures

3.1   A Chronicle of Timekeeping
        by William J. H. Andrews

3.2   Ultimate Clocks
        by W. Wayt Gibbs


Section 4: Physics

4.1   Is Time an Illusion
        by Craig Callender

4.2   What Keeps Time Moving Forward?
        by John Matson

4.3   Atoms of Space and Time
        by Lee Smolin

4.4   Inconstant Constants
        by John D. Barrow and John K. Webb


Section 5: It’s all Relative

5.1   Time and the Twin Paradox
        by Ronald C. Lasky

5.2   How Time Flies
        by John Matson


Section 6: Beyond Time

6.1   How to Build a Time Machine
        by Paul Davies


Section 7 The Alpha and the Omega

7.1   The Myth of the Beginning of Time
        by Gabriele Veneziano

7.2   Could Time End?
        by George Musser


A Question of Time

“What time is it?” That simple question is probably asked more often in contemporary society than ever before, but the answer is anything but simple. Modern scientific revelations about time make the question endlessly frustrating. Because we are bound by the speed of light and the velocity of nerve impulses, our perception of the “present” reflects the world as it occurred an instant ago - for all that human consciousness pretends otherwise, we can never catch up. Even in principle, perfect synchronicity escapes us. This eBook, A Question of Time*, summarizes what science has discovered about how time permeates and guides both our physical world and our inner selves.

*Editor's Note: Special Edition was published as A Matter of Time. The eBook adaptation contains all of the articles, but some of the artwork has been removed to optimize viewing on tablet devices. 

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