Rovelli - Reality Is Not What It Seems

Carlo Rovelli

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REALITY IS NOT WHAT IT SEEMS

The Journey to Quantum Gravity

Translated by
Simon Carnell and Erica Segre

PART ONE
Roots

PART TWO
The Beginning of the Revolution

PART THREE
Quantum Space and Relational Time

PART FOUR
Beyond Space and Time

Carlo Rovelli is a theoretical physicist who has made significant contributions to the physics of space and time. He has worked in Italy and the US, and is currently directing the quantum gravity research group of the Centre de physique thorique in Marseille, France. His Seven Brief Lessons on Physics is an international bestseller translated into forty-one languages.

The worlds most inspirational physics teacher Daily Telegraph

The new book by Carlo Rovelli is an utter joy Adam Rutherford, author of A Brief History of Everyone Who Ever Lived

Be prepared for your intellectual foundations to be vaporised Carlo Rovelli will melt your synapses with this exploration of physical reality and what the universe is formed of at the very deepest level Quantum gravity is so new that there arent many popular books about it. You couldnt be in better hands than Rovelli, a world expert Tara Shears, The Times Higher Education

A hugely engaging book, which leaves the head spinning From evaporating black holes to quantum fields, Rovelli is a charming, thought-provoking tour guide Manjit Kumar, Prospect

Theoretical physicist Carlo Rovelli plumbs this cosmic mystery [gravity] with the historical awareness and flair one might expect from the author of Seven Brief Lessons on Physics Andrew Robinson, Daily Telegraph, Books of the Year

Covering much of the same ground as his Seven Brief Lessons on Physics, this explains with style and charm how general relativity may yet be integrated with quantum theory Daily Telegraph, Books of the Year

Carlo Rovellis Reality is Not What it Seems did not disappoint. Bearing in mind the giddy expectations his surprise 2015 smash hit Seven Brief Lessons on Physics gave rise to, thats quite a feat The Big Issue, Best Books of 2016

A global superstar Professor Rovelli is making the grammar of the universe accessible to a new generation Channel 4 News

A top-flight theoretical physicist with a rock star reputation BBC Radio 4 World at One

Its not a scientific treatise. Its a paean to the wonder of the natural world I scraped a C in my Physics O-level and havent been near a physics textbook since. If I can understand and even enjoy Rovellis book, then anyone can beautiful William Cook, Spectator

Rovelli writes with elegance, clarity and charm A joy to read, as well as being an intellectual feast Michael Brooks, New Statesman

Rovelli offers a soaring vision Tom Whipple, The Times

A comprehensive guide to the bewitching adventure of physics Lewis Jones, Daily Telegraph

Carlo Rovelli is the man behind the gigantic triumph of scientific popular writing, Seven Brief Lessons on Physics His new book sets out to explore and explain some of the more difficult notions of theoretical physics. Space and time, the nature of reality, black holes, quantum theory there doesnt seem to be much that Rovelli wont attempt to explain to us nonscientists, and Reality Is Not What It Seems has more of those answers to offer Cultured Vultures

During my entire research life, friends and curious people have asked me to explain what was going on in quantum gravity research. How was it possible to study new ways of thinking about space and time? Over and over again I have been asked to write a popular account of this research. While books on cosmology or string theory abound, a book describing the research on the quantum nature of space and time, and on loop quantum gravity in particular, did not yet exist. I have long hesitated, because I wanted to concentrate on research. Some years ago, after completing my technical book on the subject, I felt that the collective work of many scientists had moved the topic to a stage mature enough for a popular book. The landscape we are exploring is enchanting: why keep it hidden?

But I still delayed the project, because I could not see the book in my head. How to explain a world without space and time? One night in 2012, during a long solitary drive from Italy to France, I realized that the only way to explain in a comprehensible manner the ongoing modifications of the notions of space and time was to tell the story from the beginning: starting from Democritus, all the way through to the quanta of space. After all, this is how I understand the story. I began to design the entire book in my mind while driving, and got increasingly excited, until I heard a police cars sirens telling me to pull over: I was driving far above the speed limit. The Italian policemen asked me politely if I was crazy to drive at that speed. I explained that I had just found the idea Id been seeking for so long; the policeman let me go without a ticket, and wished me good luck with the book. This is the book.

This book was written and first published in Italian at the beginning of 2014. Shortly afterwards, I wrote a few articles on fundamental physics for an Italian newspaper. A prestigious Italian publisher, Adelphi, asked me for an extended version of these articles, to appear as a small booklet. This is the origin of the short book Seven Brief Lessons on Physics, which to my immense surprise has become an international bestseller and has opened a beautiful channel of communication between me and so many wonderful readers all over the world. The Seven Lessons were thus written after this book, and to some extent they are a synthesis of some of the topics you find here. If you have read Seven Brief Lessons on Physics and want to know more, to journey deeper into the strange world that book sketched, here you can find more.

While the account of established physics I give here is presented from the peculiar perspective in which I understand it, it is largely uncontroversial. However, the part of this book that describes current research in quantum gravity is my own personal understanding of the state of the art. This is the region at the boundary between what we have understood and what we do not yet understand, and is still far from achieving consensus. Some of my physicist colleagues will agree with what I write here; others wont. This is true for all presentations of ongoing research at the frontiers of knowledge, but I prefer to state it upfront and clearly. This is not a book about certainties: it is a book about the adventure of moving towards the unknown.

As a whole, this is a travel book describing one of the most spectacular journeys that humanity has taken: a journey out of our limited and parochial views of reality, towards an increasingly vast understanding of the structure of things. A magical journey out of our common-sense view of things, far from complete.

Marseille, 4 May 2016

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