on 9 June 2009
The development of quantum physics through the 20th century is one of the great adventures of science, and here at last is a book aimed at the layperson which clearly explains its key concepts, while situating the scientific development in its broader setting. The result is a challenging and enthralling read.
Quantum is appropriately sub-titled, Einstein, Bohr and the Great Debate about the Nature of Reality. The long theoretical duel between these two giants of modern physics is a recurring theme of the book, but the story starts before them with the build-up to the discovery of Planck's constant at the turn of the century, and continues beyond their deaths (in 1955 and 1962 respectively) to take in Bell's Theorem and Everett's "many worlds" interpretation. Along the way we meet other great physicists such as Rutherford, Heisenberg, Pauli, Schrödinger, Dirac and Bohm.
One might suspect that a book of such scope would be in danger of being overcrowded with theories and theorists, yet Kumar rises to the challenge, displaying a novelist's sense of pacing allied with an impressive scientific clarity and succinctness. Clearly he has taken to heart the famous injunction attributed to Einstein to "make it as simple as possible, but no simpler!" He also strikes a judicious balance between scientific explanation and human context. This provided for me a welcome alternation between the physics and the lives of the physicists, with each stimulating an interest in the other.
What is so powerful and inspiring about this book is the way it conveys the passion for truth of those great pioneers. No doubt ego played its part as well, they would hardly have been human otherwise, but it is always secondary to the great quest to fathom the nature of sub-atomic reality. Characteristic of this passion is the anecdote of Bohr and Einstein on their first meeting in Copenhagen, straightaway so engrossed in debate that they repeatedly miss their bus-stop. Kumar evidently resonates to this passion, and conveys it vividly in his narrative. Here is an extract from his account of Bohr's first meeting with Schrödinger, one of Einstein's key allies in the great debate:
"After the exchange of pleasantries, battle began almost at once, and according to Heisenberg, `continued daily from early morning until late at night'... During one discussion Schrödinger called `the whole idea of quantum jumps a sheer fantasy'. `But it does not prove there are no quantum jumps,' Bohr countered. All it proved, he continued, was that `we cannot imagine them'. Emotions soon ran high... Schrödinger finally snapped. `If all this damned quantum jumping were really here to stay, I should be sorry I ever got involved with quantum theory.' `But the rest of us are extremely grateful that you did,' Bohr replied, `your wave mechanics has contributed so much to mathematical clarity and simplicity that it represents a gigantic advance over all previous forms of quantum mechanics.'
"After a few days of these relentless discussions, Schrödinger fell ill and took to his bed. Even as his wife did all she could to nurse their house-guest, Bohr sat on the edge of the bed and continued the argument. `But surely Schrödinger, you must see...' He did see, but only through the glasses he had long worn, and he was not about to change them for ones prescribed by Bohr."
This book is a brilliant and compelling account of the genesis of quantum physics, but it is more than that. In the midst of today's pervasive cynicism and disorientation, it is an inspiring reminder of what the human spirit is capable of when it devotes itself passionately to the highest aim, that of understanding the truth of our reality.
Quantum mechanics is one of the most successful scientific theories ever made. But it is utterly non-intuitive for both the scientist and non-scientist alike.
In our everyday lives, things happen for a reason - you place a fork on a table and unless someone comes along and moves it, you can be certain that it will be still there the next day. Not so in the atomic world of quantum mechanics, an electron might be here... or it might be there ... or over there. In fact it could be anywhere in the universe at any given time. Quantum mechanics predicts this behaviour in the form of a probability wave function. And it works.
But is this the true nature of reality?
This is the theme of the book. We have two great scientists - Einstein and Niels Bohr who have a fundamental difference of opinion about the nature of reality.
From Einstein's' point of view, an electron has a real set of parameters such as location, velocity, spin and so on that is independent of an observer. He admits that quantum mechanics does a good job in predicting atomic behaviour but he is convinced the theory is not complete.
On the other hand, there is Niels Bohr's vision that an electron (or any microscopic entity) has no reality until an observer chooses to measure one of its parameters. He considers quantum mechanics to be complete with no further need for revision or modification.
This argument goes on for decades. The book takes the reader through the panoply of scientists who helped put quantum theory together from its beginnings around 1900 to today. Scientists such as Max Planck, Heisenberg, Dirac, Pauli, Oppenheimer, Von Neumann and many, many others are included.
The appeal of this book is that it brings humanity to the story of quantum mechanics. It shows the egos, the fears, the ambition of these extraordinary people as the story unfolds over decades.
If you want a pure explanation of quantum mechanics then you should look to a dry text book. But if you want the human context in which quantum mechanics evolved then I recommend you read this book.
on 5 May 2010
I bought this book as a partial response to my 12 year old son's questions: "But what is infinity?" "How do we know that something is real?" He left me stumped and not a little challenged. I needed to get beyond Dr Who and thought the book might sate him.
Curiosity got the better of me and I was soon drawn into a world enriched by well drawn characters. Names that I had heard of but didn't know much about - Planck, Geiger, Rutherford, but others too, more familiar - like Hitler and GB Shaw. Others yet, I was glad to make the acquaintance of, like Wolfgang Pauli, described as a Buddha with a biting tongue. And John Stewart Bell of Belfast and Dr Bertelsmann's socks.
Quantum reads like an epic novel, with Einstein and Bohr cast as the main protagonists, with scientific truth taking the place of elusive love, an obscure object of their desires. Kumar's evocative and fluid prose describes the passion for ideas that is at the centre of the story. I didn't feel that I needed to understand it all, but understood what drove them.
But what of the science? Kumar does not shy away from the science but nor does he make it seem insurmountable to a lay reader. Boyle's law explained in a succinct paragraph is a model of elegant science writing.
There is much to commend Quantum apart from its opening up of this area of science. Kumar deftly weaves in the social and political context in which the characters are brought to life. A fundraising dinner for impoverished East European Jews hosted by Baron Rothschild in October 1930, is attended by Einstein. The septuagenarian GB Shaw toasts him: "Ptolemy made a universe which lasted 1,400 years. Newton, also, made a universe which lasted for 300 years. Einstein has made a universe, and I can't tell you how long that will last."
Einstein then speaks of moral traditions that have lasted a thousand years, and of service of life and of sacrifice. But, observes Kumar, that universe was ending `as the dark clouds of the coming Nazi storm gathered.' The previous month, the Nazis had increased their share of the vote by nearly eight times in a little over two years.
This then is a big book. A book about an icon and an iconoclast, encapsulated in one man, full of contradictions and all too human qualities. For Bohr, out of a theory came a philosophical position. For Einstein, a philosophy built on the foundations of a scientific theory was bound to be shaky.
Einstein says "..one assumes a real world existing independently from any act of perception. But this we do not know." And elsewhere "I have no better expression than `religious' for confidence in the rational nature of reality insofar as it is accessible to human reason. Wherever this feeling is absent, science degenerates into uninspired empiricism."
This reminded me a little of St Augustine's grappling with similar questions and of Pascal's Wager. There are probably a hundred other examples or more that can be cited and as many creation myths. But the ineffability of something has never stopped enquiry.
So what of quantum? Can I explain it to my son now? Well, as Kumar observes in his concluding paragraph, fifty years of `conscious brooding' had not brought Einstein any closer. I rest a little easier. In the end Einstein took solace in the words of Gotthold Lessing, a German philosopher, "The aspiration to truth is more precious than its assured possession."
For my part, I aspire to re-read this excellent book, and to yield possession of it to my son at a later date to see if he has any answers.
on 22 June 2009
I have always been fascinated by how 'it' all fits together, but struggle to find the time to concentrate on dry theoretical texts. It was therefore with great delight that I found myself engrossed in Quantum on the tube, the bus and even occasionally the walk in between. Manjit Kumar's writing eases you effortlessly into the some of the most complex ideas in physics by juxtaposing the personal stories of the authors playing out through the 20th century with the theories themselves. Sufficient detail is provided to challenge all but the most experienced reader, and a comprehensive references list encourages further exploration for those who need to dig even deeper. While having to admit to only momentary glimpses of both the elusive beauty, and the black hole enveloped by quantum theory, I felt strangely comforted that even Einstein struggled to fully embrace such a world.
on 17 October 2008
This is fascinating book written as a narrative history of those scientists who contributed to the development of Quantum Theory - one of the most important challenges to orthodox thinking in the whole history of ideas.
The book does a very good job of establishing how classical physics of the 19th Century was seen as completed and except for a few minor details that needed tidying up, the consensus was that nothing really fundamental at a theoretical level was left to discover.
Kumar explores how this certainty that physics was done and dusted came to unravel and how an idea as counter intuitive as the quantum came to be accepted by most physicists.
This manner of exploring quantum theory through its historical development allows anyone with a basic grasp of science to understand why it is so revolutionary in its implications. At the centre of this story is the struggle between Albert Einstein and Niels Bohr about what our attitude to the reality should be.
Mixing historical narrative with the scientific ideas that were in contention brings quantum theory to a much broader audience of readers than is generally possible with this sort of material.
Part social history, part popular science as well as raising questions of a philosophical nature - this makes a cracking read and comes highly recommended.
on 22 September 2011
I am a Physics teacher and recommend this book to all my A-level students. Not only is it an enjoyable read, it serves to greatly enhance their knowledge and appreciation of material we cover in class and provides them with an insight into "how science works". Unlike other books on Quantum Mechanics, this one reads like a story, making it easy for the lay person to read. It provides an in-depth account of the development of physics that completed transformed our understanding of the nature of reality, as well as a fascinating insight into the scientists at the heart of these developments. It is this compelling approach of combining biographical details of great scientists and the drama of their lives, with straightforward explanations of the science that make the book so readable. I'd recommend this book to anyone who is interested in developing their understanding of quantum mechanics and particularly to those with an interest in the history of science.
Quantum is the unfinished story of the development of quantum mechanics. Unfinished? Yes, because the question which lies at the centre of the book is not yet resolved.
The story starts in late Victorian times when classic physics seems close to completion, to being able to explain the world fully. There seem to be just a few loose ends to be tied up. However, it is those few loose ends inside the atom, explaining the nature of the electron, being able to account for light behaving both like a particle and a wave etc which lead to the unravelling (at the atomic level) of previous world views.
Through the lives of Planck, Bohr, Einstein, Schroedinger, Heisenberg, Pauli, De Broglie and others we see how diferent strands of quantum theory were hotly contested and how it developed through analysis and synthesis.
One of the most exciting things about the book to me was the rigour and power of true scientific method. Quantum physics, despite being in some ways mind blowingly ethereal is subject to the most searching challenge and detailed research. We see two of the greatest minds of the 20th century, Einstein and Bohr sitting on opposite sides of the dispute, deploying their most powerful destructive intellectual weapons in order to test the veracity of each others ideas. If ever you doudt bthe superiority of genuine science over pseudo Science (are you listening Charles Windsor), read this book.
At the centre of the dispute is the Copenhagen interpretation of Quantum mechanics, at the heart of which is the assertion that reality is not indepedent of measurement. (it would take too long to explain more, but Schrodingers famous cat is involved). Through the book we see Bohr besting Einstein, but one feels that the author is sympathetic towards Einstein and there is a sense of relief at the end of the book that the door remains open for the father of relativity.
Also fascinating is that roughly half of the book is about the major advances in the development of quantum theory in the first three decades of the 20th Century and thereafter debate switched to the interpretation, in a nutshell, is it reality or just a convenient model describing the effect of an underlying reality.
This is no dry science book however, one gets to know the people involved and the story has as its setting the major events of 20th Century history, the first world war, the rise of the nazis, the development of the atomic bomb, and the cold war.
Kumar is a clear and engaging writer, and my only two criticims would be firstly that in his efforts to be comprehensoible he maybe keeps too far away from the hard science at times. Secondly the odd summarising passage, showing briefly what the current state of play was would be helpful.
Overall, definitely recommended, it's a book for everyone, not just the scientifically minded.
on 27 May 2010
Having read the book last summer holidays, I was very impressed. A tremendous read.
The thing is, this isn't a physics book. If you want to learn quantum mechanics, go to the standard textbooks - Shankar, Sakurai, Griffiths. You're not going to get any mathematics from this, and that's not a shortcoming - that's not the point of the book.
This is about the ideas, and their evolution throughout the first three decades of the twentieth century as the quantum theory was taking shape. It's about the people who made it, and the detail about what people were wearing, what they did, their relationships is what makes this work. This book gives you flavour of what doing science is like, and is powerful in doing so. It might push you to learn more- it did for me.
I'm only starting to learn quantum mechanics, so my comments regarding the presentation might be rather limited - I intend to return to this review later to correct this - but I can already see that the topic emphasized are slightly unconventional, as other reviewer pointed out. I'm not quite sure whether that's for better or worse - but it definitely gives you a different perspective that you'll get from other sources.
The intended audience of this book? I think the layman, first and foremost, but also people like me who are about to learn quantum mechanics for real and want a little history, and a little inspiration - the book certainly succeeds in that respect.
on 17 April 2009
My wife, Audrey, nominated this book as her Guardian Readers' Book of the Year, and wrote: As a fairly innumerate non-scientist I am perversely drawn to books about maths and science and usually abandon them with my ignorance intact. However, this was so well written that I now feel an ownership of the subject, smile knowingly when I hear the word 'quantum' and feel that I've more or less got particle physics sussed. QUANTUM transcends genre - it is historical, scientific, biographical, philosophical. It is a love story of great minds living and breathing their obsessions, rivalries and divided loyalties. It is as thrilling as a whodunnit - though more of a who-might-have, who-nearly-did and who, in the end hadn't quite dunnit. I'm exhilarated by the idea of thought experiments and now practise them daily in great hopes of finding the answer which has eluded them all so far. If only I knew what a matrix was!
on 19 August 2009
This book covers the early years of the development of atomic physics. As a scientist, I am familiar with the 'names' in this field via the equations etc named after them. However, I knew little of the detailed background to their personal contributions to this field, and I found the book absolutely fascinating. Indeed, I found it difficult to put down, as the narrative was so compelling that I was keen to know 'what happened next'. It was also remarkable to read that so many of the big names were making major contributions as graduate students or young researchers. Also the wider social history was well woven into the story, from the exclusion of German scientists from major international meetings after the 1st World War, to the impact of the Nazis on German science in the 1930s.
My main quibble with the book is the title: whilst the Einstein/Bohr differences are covered, the book is about so much more than this.
I would expect interested physicists to find this a good read, but I am not so sure about the non-technical reader. For instance, the independent development of Heisenberg's matrix mechanics and Schrodinger's wave equation, and their eventual correlation, was full of interest for me, but I wonder how compelling the differences between two abstruse theories would be for the reader without a technical background.