Quantum_ Einstein, Bohr and the Great Debate About the Nature of Reality - Manjit Kumar [26]
'I will be grateful to Haller for as long as I live', Einstein had written to Mileva soon after moving to Bern in the expectation that a job at the Patent Office would sooner or later be his.48 And he was. But it was only much later that he recognised the extent of the influence that Haller and the Patent Office exerted on him: 'I might not have died, but I would have been intellectually stunted.'49 Haller demanded that every patent application be evaluated rigorously enough to withstand any legal challenge. 'When you pick up an application, think that anything the inventor says is wrong,' he advised Einstein, or else 'you will follow the inventor's way of thinking, and that will prejudice you. You have to remain critically vigilant.'50 Accidentally, Einstein had found a job that suited his temperament and honed his abilities. The critical vigilance he exercised in assessing an inventor's hopes and dreams, often on the basis of unreliable drawings and inadequate technical specifications, Einstein brought to bear on the physics that occupied him. The 'many-sided thinking' his job entailed he described as a 'veritable blessing'.51
'He had the gift of seeing a meaning behind inconspicuous, well-known facts which had escaped everyone else', recalled Einstein's friend and fellow theoretical physicist Max Born. 'It was this uncanny insight into the working of nature which distinguished him from all of us, not his mathematical skill.'52 Einstein knew that his mathematical intuition was not strong enough to differentiate what was really basic 'from the rest of the more or less dispensable erudition'.53 But when it came to physics, his nose was second to none. Einstein said he 'learned to scent out that which was able to lead to fundamentals and to turn aside from everything else, from the multitude of things which clutter up the mind and divert it from the essential'.54
His years at the Patent Office only heightened his sense of smell. As with the patents that inventors submitted, Einstein looked for subtle flaws and inconsistencies in the blueprints of the workings of nature put forward by physicists. When he found such a contradiction in a theory, Einstein probed it ceaselessly until it yielded a new insight resulting in its elimination or an alternative where none had existed before. His 'heuristic' principle that light behaved in certain instances as if it was made up of a stream of particles, light-quanta, was Einstein's solution to a contradiction at the very heart of physics.
Einstein had long accepted that everything was composed of atoms and that these discrete, discontinuous bits of matter possessed energy. The energy of a gas, for example, was the sum total of the energies of the individual atoms of which it was made up. The situation was entirely different when it came to light. According to Maxwell's theory of electromagnetism, or any wave theory, the energy of a light ray continuously spreads out over an ever-increasing volume like the waves radiating outwards from the point where a stone hits the surface of a pond. Einstein called it a 'profound formal difference' and it made him uneasy while stimulating his 'many-sided thinking'.55 He realised that the dichotomy between the discontinuity of matter and the continuity of electromagnetic waves would dissolve if light was also discontinuous, made up of quanta.56
The quantum of light emerged out of Einstein's review of Planck's derivation of the blackbody radiation law. He accepted that Planck's formula was correct, but his analysis revealed what Einstein had always suspected. Planck should have arrived at an entirely different formula. However, since he knew the equation he was looking for, Planck fashioned his derivation to get it. Einstein worked out exactly where Planck had gone astray. In his desperation to justify his equation that he knew to be in perfect agreement with experiments,