'When physics got spooky' Quantum reviewed on Salon.com

'Reading [Quantum] is a bit like lifting the hood of your mind and moving the working parts around; it's challenging and trippy -- as only the Dr. Seuss realm of the quantum can be.'

Laura Miller on Salon.com on the American edition:

'"I think I can safely say that nobody understands quantum mechanics," wrote Richard Feynman, and given that he won a Nobel Prize in physics, why should you or I want to take a shot at it? Not that you or I could plausibly claim to understand the weird, protean, paradoxical subatomic world that quantum science describes, but anyone reading Manjit Kumar's "Quantum: Einstein, Bohr and the Great Debate About the Nature of Reality" will surely feel they've gotten a bit closer. It's an exhilarating, if also disorienting, sensation.

"Quantum" orbits around the celebrated fifth Solvay conference, held in Brussels in 1927, a gathering of the greatest minds in 20th-century physics. It was at Solvay that Werner Heisenberg and Max Born presented the theory of quantum mechanics they had been working on for several years under the informal leadership of Niels Bohr. Their understanding of subatomic reality came to be called "the Copenhagen interpretation" (after the location of the Institute of Theoretical Physics, which Bohr ran), and its champions proclaimed it a "closed theory, whose fundamental physical and mathematical assumptions are no longer susceptible of any modification."

Albert Einstein, also present, disagreed, and the following decades saw a series of intense, if friendly, arguments between Einstein and Bohr -- who, as Kumar notes, had a diagram of one of Einstein's most famous thought experiments up on his office chalkboard on the day he died in 1962. That experiment, which involved the imaginary weighing of a "box filled with light" before and after a single photon is allowed to escape, is an example of the surreal mental territory that "Quantum" explores. Reading it is a bit like lifting the hood of your mind and moving the working parts around; it's challenging and trippy -- as only the Dr. Seuss realm of the quantum can be.

Kumar, a science writer in Britain (where this book was first published, two years ago), makes a point of playing up the collaborative aspects of the evolution of quantum theory, as well as the conflicts; the two can't really be separated. He begins with Max Planck's reluctant invention of the "quanta" -- an indivisible unit of energy -- in 1900. He insisted it was a mere theoretical, most likely temporary "trick," designed to get certain formulas to work properly. When, five years later, Einstein, during a period of astounding scientific creativity that included his famous paper on special relativity, suggested that light might be made up of "particle-like quanta" (later called photons), he thought of it as his most daring break with the classical physics of Newton. Light, like other forms of energy, had long been believed to flow in continuous waves, not in tiny chunks.

It was in the 1920s that quantum mechanics as we know it was born, with physicists like Heisenberg, Wolfgang Pauli, Erwin Schrödinger and Paul Dirac scrutinizing each other's proposals, seizing upon weak spots to investigate, discovering little-known laboratory data or mathematical methods that might provide a solution and writing important papers only to find that some theoretician in the hinterlands had gotten there first. It was, as Kumar puts it, "a golden age ... unparalleled since the scientific revolution in the 17th century led by Galileo and Newton." The dollops he offers of these scientists' personal lives and youths emphasize the importance of teachers, mentors and patrons, as well as those rare individuals, like Bohr, whose tact and generosity aided in keeping things collegial. (By contrast, 17th century science was impeded by the paranoia and secrecy of Newton.)

That it can be hard to wrap your brain around the principles of the subatomic world is a given. It's a strange kingdom, full of things that don't exist or exist in two opposite conditions at once until somebody looks at them, particles that influence each other instantaneously despite being separated by lightyears and electrons that move from one place to another without traveling through the space in between. Books on the subject rely on good metaphors, clearly explained, and Kumar delivers them, but "Quantum" is not for the complete novice or those timid souls who quail at the sight of an equation. (I can't claim to understand the few equations Kumar includes myself, but they don't scare me away, and I found this book is perfectly intelligible even though I can't do the math.)

Much of the debate between Einstein and Bohr revolved around Einstein's intuitive rejection of the implication of the Copenhagen interpretation -- which is that objective reality, independent of any observer, doesn't really exist. Bohr, by contrast (and sounding a lot like Wittgenstein), insisted that physics isn't concerned with what is but solely with what we can say about it. Not only were these two geniuses battling over where to draw the line between the familiar, cause-and-effect world of classical Newtonian physics and the quantum Wonderland, they were sketching, erasing and resketching the boundary between science and philosophy, debating the nature of reality itself.

Einstein was for many years regarded as a stubborn, even senile holdout against the quantum gospel, but Kumar finds that view simplistic. "Quantum" concludes by surveying developments since the deaths of Bohr and Einstein, such as Bell's Theorem and the many worlds interpretation, some of which point to critical problems that the Copenhagen interpretation left unresolved. (One is how the phenomenon of the universe came to be in the first place if there was no one to observe the Big Bang.) All of this, the author maintains, has led to "a reconsideration of the long-standing verdict against Einstein in his long-running debate with Bohr." Instead, he paints Einstein as a partisan of that most precious of scientific tools: the question. That's why he ends with one of the physicist's favorite quotations, from the German philosopher Gotthold Lessing: "The aspiration to truth is more precious than its assured possession.'


Meanwhile the book has been selling well in Calgary in Canada - see this bestseller list.

Quantum on BookClubForum

Book Club Forum contributor Andrea had this to say about Quantum recently:

'Finished Quantum last night and I have to say it was absolutely brilliant! I've never read such a riveting and enthralling science book. To be fair, it's not just science it's a narrative history of the development of qunatum physics and focuses on a debate between Einstein and his rival, Bohr. The science bits are broken up enough by the story to make it very readable. It was great to meet all those famous names as well, like Einstein, Heisenberg and Schrodinger, to meet the personalities not just the scientists. It was fascinating to discover that Einstein struggled with maths and had to receive help developing his theory of relativity. A lot of the book takes place against the backdrop of WW2 as well; there's a good deal of drama here.'

'If you're at all interested in physics, and particularly in particle physics then I'd thoroughly recommend this. It's not just science, it's history and philosophy too.'

'I still don't understand quantum physics. But I'm all the more astonished by its weirdness and I've been very inspired to read more about it.'

You can follow and add to the thread here.

Quantum - American reviews

Here are some snippets of the press Manjit Kumar's book has been getting stateside:

Library Journal:

'Science editor and writer Kumar (coauthor, Science and the Retreat from Reason) adds to the growing number of popular works on the history of quantum mechanics and to the continuing debate on the sufficiency of quantum theory as a representation of "reality." He devotes the bulk of his book to the work and the debates of the physicists who developed quantum mechanics in the first half of the 20th century. Almost inevitably, Kumar repeats many of the quotes from Bohr, Einstein, and other greats that have already been offered by authors of similar works. His greatest strength is his clear discussion (without mathematics) of the advances and debates in the discipline. The last few pages of the text carry the history of physics into the 21st century as experiments continue to support the standard theory but do not yet end the discussion.'

'VERDICT This is especially good for lay readers who would enjoy an excellent story about the long struggle of scientists to understand an important field of modern science.'

Kirkus Reviews:

'A staggering account of the scientific revolution that still challenges our notions of reality. Kumar provides a gripping narrative of the birth of atomic physics in the first half of the 20th century ... Kumar evokes the passion and excitement of the period and writes with sparkling clarity and wit. Expertly delineates complex scientific issues in nontechnical language, using telling detail to weave together personal, political and scientific elements.'

I Liked Reading:

'This is a great book. If you are interested in the weird and wonderful quantum world, then you will find this book a fantastic read that flows very well from chapter to chapter and instantly engages you. What is particularly refreshing about Quantum is how it weaves in information about the personalities who were engaged in the scientific pursuit themselves rather than focusing exclusively on the science ... even if you know nothing about quantum theory then finding out more about it may be particularly exhilarating. Read it!'

Booklist:

'Kumar keeps the main thread of his narrative accessible to the intelligent general reader, particularly clarifying how Einstein’s belief in objective reality pits him against the daringly agnostic Bohr, who leaves the mysteries of wave-particle duality veiled in statistical probabilities and abstract formulas. Intellectual exhilaration runs high as Einstein repeatedly presses Bohr—posing daunting questions about how to weigh an imaginary box of light and how to explain eerily “entangled” particles. The future of science hangs in the balance: physics becomes high drama.'

'Manjit Kumar breathes new life into this classic story through superb writing and careful research'

'Just as with the history of all other human endeavors, science has its list of “greatest hits,” dramatic stories that will be told and retold, generation after generation, ad infinitum. Of these, the birth of quantum theory seems destined to be foremost: Other narratives may rival in their sweeping scopes, scenic settings, and cast of characters, but no other area of science has raised deeper questions about the very nature of reality. In Quantum, Manjit Kumar breathes new life into this classic story through superb writing and careful research, focusing on a philosophical conflict between Niels Bohr and Albert Einstein that still resonates through physics to this day.'

The American edition of Quantum reviewed in Seed magazine.