Roger Penrose - The Road to Reality 

Roger Penrose: The Road to Reality: A Complete Guide to the Laws of the Universe, Pub: Jonathon Cape, 29 July 2004 (UK)/Knopf, Feb 2005 (US), 1094 pages

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"Professional scientists cannot accuse Mr. Penrose of dumbing-down the science, and the author's prose is so lucid the reader can grasp his point even when the mathematics fly overhead." - Michael Shermer, NY Sun review

The Road to Reality by Roger Penrose is 1094 pages long, and provides a comprehensive account of our present understanding of the physical universe, and its underlying mathematical theory.

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Claim to Fame

Roger Penrose has worked in many areas of mathematical physics and cosmology, but is perhaps most famous for his collaboration with Stephen Hawking. Together, they proved that, in the mathematical model of general relativity, our universe was originally contained within a sphere of zero radius. That is, all space and matter was contained within a point called a singularity. They also proved that space, time and matter had a beginning in what is called the big bang.

Penrose holds the most respected chair in mathematics at Oxford, just as Hawking holds the most respected chair at Cambridge. Stephen Hawking's A Brief History of Time and The Universe in a Nutshell introduced mathematical physics without using equations, and kept things simple. If you want equations, and more depth, then The Road to Reality by Roger Penrose is a must buy.


This book provides the mathematical background needed for understanding physical theories through the same equations that theoretical physicists use in their everyday work. The aim is to convey a detailed overall understanding - a feeling for the deep beauty and philosophical connotations of the subject, as well as of its intricate logical interconnections. 

It's a challenging read, but there is enough descriptive material to carry the less mathematically inclined reader through, as well as some 450-500, mostly hand-drawn, figures. The book provides a feeling for all the key issues and deep current controversies, and counters the common complaint that the details of cutting-edge science are fundamentally inaccessible. 

The topics covered include: the roles of different kinds of numbers and geometry in physics; the ideas - and magic - of calculus; notions of infinity; the physics and mathematics of relativity theory; the foundations and controversies of quantum mechanics; the standard model of particle physics; cosmology; the big bang; black holes; the profound challenge of the second law of thermodynamics; string and M theory; loop quantum gravity; twistors; fashions in science; and new directions.

escher circle limit 1, Roger Penrose: Road to Reality

Escher's Circle Limit 1 represents the conformal hyperbolic plane, and is used by Roger Penrose to illustrate his favourite mathematical model of the universe. It's just one of 450-500 pictures in the book.

Quote from the book

Knowing where to find things is as important as knowing things. Here's a quote on this idea worth the price of the book:

"There is one major breakthrough in 20th century physics that I have yet to touch upon, but which is nevertheless among the most important of them all! This is the introduction of, an online repository where physicists and mathematicians, biologists and computer scientists can publish preprints (or 'e-prints') of their work before (or even instead of!) submitting to journals."

Quote from the Scotsman review

"Is [The Road to Reality] the most important science book of the century? We had better wait until 2099 to find out - but I am sure Roger Penrose would be the first to say no. His greatest hope is that there is some young person out there...who will do for our century what Einstein did for the last, and who will clear up the mysteries that Penrose, Hawking, Witten and so many others have been unable to solve.

The Road To Reality ends with such a vision; and if it comes to fruition then this book will one day seem little more than a historical curiosity. In that case it will have succeeded - so let’s hope it goes on library shelves everywhere and finds its way into the hands of the next Einstein, wherever he or she may be."
- Andrew Crumey