Einstein and the Quantum reveals for the first time the full significance of Albert Einstein's contributions to quantum theory. Einstein famously rejected quantum mechanics, observing that God does not play dice. But, in fact, he thought more about the nature of atoms, molecules, and the emission and absorption of light -- the core of what we now know as quantum theory -- than he did about relativity.Max Planck proposed a quantum theory of light in 1900, and Einstein proposed to extend it by saying that light was fundamentally composed of particle. Stone says that Planck and Lorentz argued with that, saying that Einstein had gone too far.
A compelling blend of physics, biography, and the history of science, Einstein and the Quantum shares the untold story of how Einstein--not Max Planck or Niels Bohr--was the driving force behind early quantum theory. It paints a vivid portrait of the iconic physicist as he grappled with the apparently contradictory nature of the atomic world, in which its invisible constituents defy the categories of classical physics, behaving simultaneously as both particle and wave. And it demonstrates how Einstein's later work on the emission and absorption of light, and on atomic gases, led directly to Erwin Schrödinger's breakthrough to the modern form of quantum mechanics. The book sheds light on why Einstein ultimately renounced his own brilliant work on quantum theory, due to his deep belief in science as something objective and eternal.
Stone is wrong where he says that Einstein's view of light was ultimately proved correct 20 years later. It was not. Planck's view is closer to the modern view that light is quantized when absorbed or emitted (ie, observed), but has wave properties otherwise.
There are modern textbooks that say that light is composed of particles, but then they say that they are a very funny kind of particle that can be in two places at once, obey probabilistic laws for existence, and show interference patterns like a wave. To me this is like saying that a dog is a cat, if you suitably redefine dog and cat. Light is not composed of particles, as the words were understood in Einstein's day.
People like to credit Einstein, but the fact is that he stubbornly refused to accept quantum mechanics his whole life. An essential part of the theory is that light and matter have wave properties that are quantized when observed. Planck brilliantly stumbled on that idea in 1900, and Einstein always rejected it.
Why is Einstein’s role in quantum theory important and interesting?No relativity was not individual genius. Nearly all of the good ideas came from Lorentz, Poincare, Grossmann, and others. And Einstein contributed very little to quantum mechanics.
It is important because a careful examination of the historical record shows that Einstein was responsible for more of the fundamental new concepts of the theory than any other single scientist. This is arguably his greatest scientific legacy, despite his fame for Relativity Theory. He himself said, “I have thought a hundred times more about the quantum problems than I have about Relativity Theory”. It is interesting because he ultimately refused to accept quantum theory as the ultimate truth about Nature, because it violated his core philosophical principles.
So you are saying that Einstein is famous for the wrong theory?
In a certain sense, yes. All physicists agree that the theory of relativity, particularly general relativity, is a work of staggering individual genius.
Update: Stone says:
I was absolutely staggered to discover that the most famous scientist in human history actually wasn't getting as much credit as he deserved.This is crazy. Einstein did recognize discoveries by Planck and Bose, but did not add much.