Introduction
What If? Why Us? Why Now?
by Jesse Emspak

Section 1: Undiscovered Worlds

1.1   Parallel Universes
        by Max Tegmark

1.2   Extraordinary Claims
        by George F. R. Ellis

1.3   The Great Cosmic Roller-Coaster Ride
        by Cliff Burgess and Fernando Quevedo

Section 2: Explorations

2.1   Cracking Open a Window
        by George Musser

2.2   Out of the Darkness
        by Georgi Divali

Section 3: Multiple Dimensions

3.1   Looking for Life in the Multiverse
        by Alejandro Jenkins and Gilad Perez

3.2   Quantum Gravity in Flatland
        by Steven Carlip

3.3   The Universe’s Unseen Dimensions
        by Nima Arkani-Hamed, Savas Dimopolous and Georgi Divali

Section 4: Time and Time Again

4.1   Quantum Physics of Time Travel
        by David Deutsch and Michael Lockwood

4.2   The Myth of the Beginning of Time
        by Gabriele Veneziano

4.3   Been There, Done That
        by George Musser

Section 5: Why We Live Now

5.1   The String Theory Landscape
        by Raphael Bousso and Joseph Polchinski

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

5.3   The Inflation Debate
        by Paul J. Steinhardt