In his 1932 Nobel-prize lecture delivered on 11 December 1933, Werner Heisenberg declared that “the path so far traced by the quantum theory indicates that an understanding of those still unclarified features of atomic physics can only be acquired by foregoing visualisation and objectivisation to an extent greater than that customary hitherto”.

Philipp Lenard

He may not, of course, have foreseen that this kind of proposition – together with Einstein’s relativity – was precisely what was later defined as highly undesirable “Jewish physics” by the Nazi government in Germany. Indeed, Heisenberg was eventually investigated by SS chief Heinrich Himmler. Himmler decided that it was in the interests of the Nazi regime to leave Heisenberg alone, despite attempts by disreputable individuals such as the physicists Philipp Lenard and Johannes Stark – hypnotized as they were by Nazi obsessions – to dispose of Heisenberg, whom they saw as a “white Jew”.

Heisenberg is one of the central characters – perhaps the central character – in John Cornwell’s readable account of the history of German science, mathematics and technology during, and shortly before, the infamous Nazi era. As Cornwell observes: “Heisenberg’s pact with the [Nazi] regime was an implicit agreement to separate science from the scientist – theoretical physics from Einstein’s Jewishness. It was a shameful act, and it was done under duress.”

It would, of course, have been astonishing if a major European power such as Germany had not produced many scientists and engineers of great distinction or even genius during that period. Indeed, about one-third of all Nobel laureates in 1933 were German citizens. On the other hand, its national reputation had already been tarnished by events such as the first sinking of a civilian liner (the Lusitania) by a German U-boat in 1915 and by the introduction of poison gas as a tactical weapon during the First World War. Both episodes relied on German work in science and technology. As Cornwell asks: was this Germans behaving as Germans, or scientists in Germany behaving as scientists?

Worse was to come with the advent of the Nazi government in 1933. The “poison-gas scientists”, with their pseudo-logical excuses for the lethal consequences of their work, were followed by the even more pernicious practitioners of Nazi racial hygiene and eugenics. Disreputable voices began to emerge from the murky background, complaining about the alleged waste of resources on people who were mentally ill, which ultimately led to a programme to get rid of “life unworthy of life”. Anti-semitism – promoted by the central authorities – grew exponentially.

In physics, it is probably enough to list some of the famous names of those who were forced out of Germany in the 1930s. They included Bethe, Bloch, Born, Debye, Einstein, Franck, Gabor, Gustav Hertz, Herzberg, Hess, Hevesy, Schrödinger, Stern and Wigner, as well as the mathematicians Richard Courant, Emmy Noether and Hermann Weyl. The names will be familiar to anyone with an interest in physics or the physical sciences.

As Cornwell accurately points out: “In the lethal mix of power, fear, cruelty and dilettantism, pseudo-science began to flourish virtually unchallenged under the auspices of the SS in Hitler’s Germany. The direction of SS-sponsored ‘researches’ in time brought appalling suffering and death to their victims and degradation upon all those associated with their conduct and data.”

Perhaps those who remained (as far as was possible) outside the Nazi mainstream were later sustained by Planck’s advice to Heisenberg in 1933. “If we can guide even small groups of talented and right-minded young through these horrible times,” advised Planck, “we shall have done a great deal to ensure Germany’s resuscitation after the end.”

There are, however, profoundly irreducible difficulties with this opinion. For example, in 1943 Heisenberg visited the ancient Jagiellonian University of Krakow in Poland, to which he had been invited by the infamous governor-general Hans Frank, who was later hanged at Nuremberg after the war. There Heisenberg gave a lecture on modern physics to a lay “Germans-only” audience. As he spoke, 184 members of the professorial staff of the university were languishing in a concentration camp. They had been lured some months earlier to a meeting – supposedly to discuss the re-opening of the university – and then treacherously arrested by Frank’s henchmen.

More generally, the Polish intelligentsia was being systematically destroyed in accordance with detailed policies formulated before the Second World War. A special list was prepared in Berlin of 61,000 (sic) members of the Polish intelligentsia who were to be arrested and killed as German forces entered the country. Some 45 professors of the University of Lwow (now Lviv) – and even some members of their families – were identified by name and were executed on the first week of German occupation in 1941. Many of these people were well known to members of the German academic establishment.

Those scientists who, in effect, followed Planck’s advice and stayed in Germany must have known what was going on. Indeed, there is convincing evidence that they did know. Dubbing them “fellow travellers in the Nazi regime”, Cornwell points out that these scientists “remained on the face of it morally and politically aloof while arguing that science is an apolitical, neutral pursuit”.

Then there is the question of the bomb. Cornwell describes the famous period during 1945 when leading German scientists, including Heisenberg, were held under house arrest at Farm Hall near Cambridge by the British authorities. The author discusses the transcripts of the secret recordings that were made of their conversations, from which it seems reasonably clear that Heisenberg did not really understand the practical physics of the underlying bomb-making process. It is also clear that Walter Gerlach, who was among those detained at Farm Hall, was, in principle, willing to use Germany’s nuclear discoveries. “If Hahn has made this discovery, let us at least be the first to make use of it,” he said. Fortunately they did not succeed, and they all tried to hide behind their last refuge – patriotism.

The final 37-page section entitled “Science from the Cold War to the war on terrorism” is a kind of paternoster addressed to scientists and others. Those who have already been converted will welcome it. Those who have not will wonder how it really relates to what came before. The publishers describe this volume as an “epic and unique chronicle”. It is not quite that, but it is a useful, well presented and reasonably priced introduction to an important subject.