Quantum_ Einstein, Bohr and the Great Debate About the Nature of Reality - Manjit Kumar [62]
Work had only just begun when a letter arrived that unsettled Bohr. It was from Rutherford, who was offering him a permanent professorship in theoretical physics back in Manchester. 'I think the two of us could try and make physics boom', wrote Rutherford.55 It was tempting, but Bohr could not leave Denmark just as he was about to be given everything that he wanted. Maybe if he had gone, Rutherford would not have left Manchester in 1919 to take over from J.J. Thomson as the director of the Cavendish Laboratory at Cambridge.
Always known as the Bohr Institute, the Universitetets Institut for Teoretisk Fysik was formally opened on 3 March 1921.56 The Bohrs had already moved into the seven-room flat on the first floor with their growing family. Following the upheavals of war and the hardship of the years that followed in its wake, the institute was soon the creative haven Bohr hoped it would be. It quickly became a magnet for many of the world's brightest physicists, but the most talented of them all would always remain an outsider.
Chapter 5
WHEN EINSTEIN MET BOHR
'Those are the madmen who do not occupy themselves with quantum theory', Einstein told a colleague as they looked out of the window of his office in the Institute of Theoretical Physics at the German University in Prague.1 After his arrival from Zurich in April 1911, he had been puzzled as to why only women used the grounds in the mornings and only men in the afternoons. As he struggled with his own demon he discovered that the beautiful garden next door belonged to a lunatic asylum. Einstein was finding it difficult to live with the quantum and the dual nature of light. 'I wish to assure you in advance that I am not the orthodox light-quantizer for whom you take me', he told Hendrik Lorentz.2 It was a faulty impression that arose, he claimed, 'from my imprecise way of expressing myself in my papers'.3 Soon he gave up even asking if 'quanta really exist'.4 By the time he returned from the first Solvay conference in November 1911 on 'The Theory of Radiation and the Quanta', Einstein had decided that enough was enough and pushed the lunacy of the quantum to one side. Over the next four years, as Bohr and his atom took centre stage, Einstein effectively abandoned the quantum to concentrate on extending his theory of relativity to encompass gravity.
Founded in the mid-fourteenth century, Prague University was divided in 1882 along lines of nationality and language into two separate universities, one Czech and the other German. It was a division that reflected a society where Czechs and Germans harboured a deep-seated suspicion and mistrust of each other. After the easy-going, tolerant atmosphere of Switzerland and the cosmopolitan mix of Zurich, Einstein was ill at ease in spite of the full professorship and the salary that enabled him to live in some comfort. It provided just a quantum of solace against the creeping sense of isolation.
By the end of 1911, as Bohr contemplated his move from Cambridge to Manchester, Einstein desperately wanted to return to Switzerland, and it was then that an old friend came to his rescue. Recently appointed as the dean of the mathematics and physics section of the Swiss Federal Technical University (ETH), Marcel Grossmann offered Einstein a professorship in Zurich at the renamed former Polytechnic. Although the job was his, there were formalities that Grossmann had to observe. High on the list was seeking the advice of eminent physicists about Einstein's possible appointment. One of those asked was France's premier theorist, Henri Poincaré, who described Einstein as 'one of the most original minds' he knew.5 The Frenchman admired the ease with which he adapted to new concepts, his ability to see beyond classical principles, and when 'faced with a physics problem, [he] promptly envisages all possibilities'.6 Where Einstein had once failed to get a job as an assistant, in