John Gribbin - Computing with Quantum Cats: From Colossus to Qubits

This book grew out of conversations with the quantum computer group at Sussex University, in particular Winfried Hensinger, who opened my eyes to the dramatic progress now being made in the practical application of ideas that seemed esoteric even a few years ago. I already knew something about those esoteric ideas thanks to David Deutsch, of the University of Oxford, and Terry Rudolph, at London's Imperial College. Thanks also to the helpful people at Bletchley Park, Gonville and Caius College, Cambridge, and the David Bohm Archive at Birkbeck College, London; and to John Carl, Frank Carter, Terry Clark, David Darling, Artur Ekert, Lucien Hardy, Mark Hogarth, Betty Houghton, Tero Keski-Valkama, Tony Leggett, Lawrence Lerner, Irfan Siddiqi and Michelle Simmons.

The schoolboy Alan Turing in the mid-1920s.

A letter home that he wrote using a fountain pen he had made himself.

Twenty years later he was a talented long-distance runner.

Bletchley Park, Hut 3, where Turing worked on Enigma.

One of the Hut 3 teams at work.

Two Wrens working with Colossus, the world's first electronic programmable computer.

Two of the American computer pioneers, Presper Eckert (left foreground) and John Mauchly (leaning on pillar), with the Electronic Numerical Integrator and Computer (ENIAC) at the University of Pennsylvania, around 1946.

Johnny von Neumann (right) with Robert Oppenheimer in front of the Institute for Advanced Study computer, 1952.

A brochure for the Bendix G-15 computer, 1955. This machine was based on Turing's ACE design.

Astronomer Fred Hoyle with a model radio telescope used in the TV production of his play A for Andromeda, which featured Julie Christie (1961).

A version of the game of life in which squares live, die, or reproduce according to their relationship with adjacent squares.

The greatest gathering of physicists everSolvay Congress, October 1927. Delegates included quantum pioneers Albert Einstein, Max Planck, Paul Dirac, and Erwin Schrdinger.

A set of double-slit diffraction patterns for light.

Entanglement apparatus in the lab of Anton Zeilinger, Vienna.

Quantum physics at work: an MRI scanner in operation.

John Bell, who stimulated research that proved the world does not conform to local reality.

David Bohm, who challenged conventional quantum wisdom.

Hans Dehmelt, who shared the 1989 Nobel Prize in physics for his work with ion traps.

Alain Aspect, who measured the Bell inequalities.

Brian Josephson celebrates the news of his share of the Nobel Prize in 1973.

David Wineland (left) and Serge Haroche, the joint winners of the 2012 Nobel Prize in physics.

Wineland with an ion trap device.

World chess champion Gary Kasparov (right) ruminates before making his first move in a chess game against the computer Deep Blue, 1997. Deep Blue won the series 32.

Ion trap laboratory at the University of Sussex. The inset shows the chip itself, with electrodes 2 micrometers thick and 130 micrometers wide, at the heart of the experiment.

Getting from ENIAC to the iPhone took less than a human lifetimethreescore years and ten. If quantum computer technology is tamed, the next 70 years will see even greater advances.