The essays in this book look at the question of whether physics can be based on information, or – as John Wheeler phrased it – whether we can get “It from Bit”. They are based on the prize-winning essays submitted to the FQXi essay competition of the same name, which drew over 180 entries.

The eighteen contributions address topics as diverse as quantum foundations, entropy conservation, nonlinear logic and countable . Together they provide stimulating reading for all physics aficionados interested in the possible role(s) of information in the laws of nature.

The Foundational Questions Institute, FQXi, catalyzes, supports, and disseminates research on questions at the foundations of physics and cosmology, particularly new frontiers and innovative ideas integral to a deep understanding of reality, but unlikely to be supported by conventional funding sources.

Table of Contents

1 Introduction

2 "It from Bit" and the Quantum Probability Rule

3 It from Qubit

4 Drawing Quantum Contextuality with 'Dessins d'enfants'

5 The Tao of It and Bit

6 Information-Based Physics and the Influence Network

7 Relative Information at the Foundation of Physics

8 Information and the Foundations of Quantum Theory

9 An Insight into Information, Entanglement and Time

10 These from Bits

11 Self-similarity, Conservation of Ent ropy/ bits and the Black Hole Information Puzzle

12 Spacetime Weave---Bit as the Connection Between Its or the Informational Content of Spacetime

13 Now Broadcasting in Planck Definition

14 Is Spacetime Countable?

1 5 Without Cause

16 Reality, No Matter How You Slice It

17 Bit from It

18 Contextuality: Wheeler's Universal Regulating Principle

Chapter 19It from Bit from It from Bit ... Nature and Nonlinear Logic