The main result reached by the new theory was that the classical mechanics can be made to account for the whole range of spectral phenomena, provided entirely new meanings are given to such symbols as p and q which had hitherto been taken to describe the position and motion of the electron. ...The most significant of the new properties is that the product pq is no longer the same as the product qp - in other words the order in which the two factors are multiplied together is no longer a matter of indifference. The difference between pq and qp is found to be always the same, being Plank's constant h multiplied by a numerical multiplier.

In the interior of the atom, Bohr had tried the plan of retaining the particle-electron and modifying the classical mechanics. Heisenberg took the opposite cou…

We saw that radiation cannot suitably be pictured as particles when it is traveling through space. There is a corresponding property for electrons; these shoul…

A similar situation occurred in astronomy, where the Newtonian law of gravitation had been found to predict the orbits of the outer planets with great accuracy…

Light and matter are both single entities, and the apparent duality arises in the limitations of our language. It is not surprising that our language should be…

I am acutely aware of the fact that the marriage between mathematics and physics, which was so enormously fruitful in past centuries, has recently ended in div…

Quaternions came from Hamilton after his really good work had been done, and though beautifully ingenious, have been an unmixed evil to those who have touched …