Simon & Schuster £25 pp675

By the time of Albert Einstein’s death in 1955, the FBI had a 1,427-page dossier on him. For years, they had been trying to nail him as a dangerous subversive, but, in the event, they found nothing of substance. The dossier was remarkable only for its inaccuracies and omissions. J Edgar Hoover’s goons had even missed his affair with Margarita Konenkova, a Russian spy. Nine of his love letters became public in 1998. Even this, however, leaves him without a stain on his political character. He had no idea the lady was a Soviet spook.

The FBI pursued him partly because of his political history of pacifism, his dislike of the nation state and his dissident insistence that America should abide by the terms of its own constitution. But there was also his stardom. Einstein was a global celebrity when he arrived in America in 1933, and over the next 22 years he became even more firmly established as the image of science, of genius itself. He was bigger than Hoover, bigger than the cold war, bigger than all contemporary concerns. “Politics is for the present,” he said, “while our equations are for eternity.” Perhaps the real crime the FBI was investigating was blasphemy. Eternity? This guy had a hotline to God.

His status remains unchanged. His appearance when he was at Princeton (electrocuted hair, droopy moustache, baggy clothes, impenetrable air of distraction) still embodies, in the popular imagination, the word “genius”, a fully deserved title. His scientific achievements remain beyond all doubt. Next to the Himalayas of Newton and Einstein everyone else looks as flat as Norfolk.

Writing his biography is thus peculiarly challenging. There are more than 200 books on the man’s life. Furthermore, every part of Einstein seems to touch everything else. Either he is like Shakespeare (knowing everything while being nothing himself) or Mozart (hearing secret harmonies beyond the range of ordinary mortals). The celebrity and the politics make matters worse by turning his story into the history of his times.

But Walter Isaacson is level-headed. He also has the huge advantage of a mass of personal letters released last year. He is, by profession, a businessman (the former chief executive of CNN) and he is businesslike in his writing. He is also not a physicist, so he is obliged to work hard to translate the science into lay terms. It works. This is a readable, dramatic and revelatory book that persuasively connects character, work and context.

Thematically, the life divides into two distinct phases. The first is revolutionary. It ends in 1915 with general relativity, a theory of gravity so beautiful that it can induce aphasia in otherwise loquacious scientists. This rounded off the theory of special relativity, published in 1905, by introducing us to the great weirdness of the curvature of space-time. Newton was dead; long live Einstein.

Isaacson assiduously links this work to the character. Einstein was an outcast, impatient with what he took to be intellectual irrelevancies – a trait that was to rebound on his highly intelligent but troubled first wife, Mileva Maric. The new personal details that have emerged show a man oscillating between immense sweetness and a carelessness amounting to brutality – a daughter, Lieserl, he had with Maric was simply discarded and he had repeated, often callously conducted affairs. In the event, the lack of intellectual ambition of his second wife, Elsa, was to prove a more durable way of containing his intense self-indulgence, though the flirtations and affairs continued. He was also difficult to contain professionally. Before, during and immediately after 1905, he was incapable of securing an academic post. In fact, he didn’t need one. He was perfectly able to think while working as a patent clerk in Bern.

But physics, the nature and history of matter, always kept him on the straight and narrow. In his early work, he took a top-down approach, starting from simple thought experiments. The question that set him on the road to relativity was: what would it be like to travel on a beam of light? This took him right through to 1915 – space-time curvature can be explained in terms of a bowling ball on a trampoline.

Isaacson persuasively connects these insights to the cultural climate of the time. This was the era of modernism, a bonfire of certainties. Einstein and Picasso shared an intuitive sense that the world was ready to be reimagined.

But Isaacson has to tread carefully here. It is all too easy to misinterpret the word “relativity”. Many suggested – including, later, the Nazis – that Einstein had “relativised” everything, morals and values included. This led to relativity being much too closely identified with artistic modernism. In fact, relativity rests on very solid, deterministic grounds. There is nothing relative about the speed of light, and Einstein’s universe was as much a predetermined mechanism as Newton’s. He was a classicist, believing the universe was a system of cause and effect that could, ultimately, be deciphered by reason, by the application of high common sense. His misfortune was that he had failed to realise the extent to which his own theories threatened the very foundations of classicism.

After general relativity, Einstein was the magus celebrity, the keeper of the keys to the cosmos. One new paper of his was pasted up in the window of Selfridges in London, not so that people could read it – how could they? – but so they could look at it and wonder. But, by then, the life entered the second phase. Intellectually, this was one long crisis. Both relativity and quantum theory (another product of the annus mirabilis of 1905) had turned on their maker. The first because it predicted an unstable universe, and the second because it appeared to show that the anticlassical workings of chance lay at the heart of matter.

He was too much of a classicist to accept this. God may be elusive, but he was not a malicious dice-player. Einstein was a religious unbeliever. He was awestruck by his discoveries and never rejected the possibility of the workings of some higher force. Nevertheless, he was convinced a personal, intervening God was simple delusion.

Isaacson misses a trick here. He repeatedly portrays Einstein as a radical, out-of-the-box thinker, a rebel against authority. But, in fact, his later work shows him desperately trying to climb back into the box of classicism. In addition, his constant evocations of God are made in the manner of a man seeking rather rejecting authority. He was, in the end, a supremely conservative thinker.

The latter half of his life, until his death in 1955, was spent in a futile attempt to mould the whole gigantic structure into a unified field theory. His colleagues looked on in pity. “Einstein, Einstein, Einstein,” murmured the scientist Niels Bohr repeatedly. Einstein’s compensation was his celebrity and his increasingly complex political involvements. Isaacson sees consistency in his politics in that he fought oppression, regimentation and state power, but this, to me, says little. In reality, his politics were, although well intended, seldom well thought out.

His private life, we now know, was messier than average, though perhaps not by celebrity standards. But he was loved, fiercely, by women and the world. He died nobly, having refused a last-chance operation, scrawling his final equations and speaking his native German in the presence of an uncomprehending nurse. With prodigious effort and businesslike calm, Isaacson has given us much more than Einstein the magus, he has given us Einstein the mensch.

www.bryanappleyard.com

Einstein is available at the Books First price of £23 (including p&p) on 0870 165 8585

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