Classical mechanics has been developed continuously from the time of Newton and applied to an ever-widening range of dynamical systems, including the electromagnetic field in interaction with matter. The underlying ideas and the laws governing their application form a simple and elegant scheme, which one would be inclined to think could not be seriously modified without having all its attractive features spout. Nevertheless it has been found possible to set up a new scheme, called quantum mechanics, which is more suitable for the description of phenomena on the atomic scale and which is in some respects more elegant and satisfying than the classical scheme. This possibility is due to the changes which the new scheme involves being of a very profound character and not clashing with the features of the classical theory that make it so attractive, as a result of which all these features can be incorporated in the new scheme.
Paul DiracRelated topics
atomic character clashing classical description due field found form having interaction matter mechanics modified possibility possible quantum result set simple Laws newtonRelated quotes
The most immediate result of this unbalanced specialisation has been that to-day, when there are more "scientists" than ever, there are much less "cultured" men than, for example, about 1750. And the worst is that with these turnspits of science not even the real progress of science itself is assured. For science needs from time to time, as a necessary regulator of its own advance, a labour of reconstitution, and, as I have said, this demands an effort towards unification, which grows more and more difficult, involving, as it does, ever-vaster regions of the world of knowledge. Newton was able to found his system of physics without knowing much philosophy, but Einstein needed to saturate himself with Kant and Mach before he could reach his own keen synthesis. Kant and Mach - the names are mere symbols of the enormous mass of philosophic and psychological thought which has influenced Einstein.
José Ortega y Gasset
Not only was he ignorant, but he had not even those conditions within himself which made knowledge possible. All that there was developed of him, at present, was a fund of energy, self-esteem, hope, courage, and daring, the love of action, life, and adventure; his life was in the outward and present, not in the inward and reflective; he was a true ten-year old boy, in its healthiest and most animal perfection. What she was, the small pearl with the golden hair, with her frail and high-strung organization, her sensitive nerves, her half-spiritual fibres, her ponderings, and marvels, and dreams, her power of love, and yearning for self-devotion, our readers may, perhaps, have seen. But if ever two children, or two grown people, thus organized, are thrown into intimate relations, it follows, from the very laws of their being, that one must hurt the other, simply by being itself; one must always hunger for what the other has not to give.
Harriet Beecher Stowe
The interest of research workers has frequently been focused on the phenomenon of regularly shaped crystals suddenly forming from a liquid, e.g. a supersaturated salt solution. According to the atomic theory the forming force in this process is to a certain extent the symmetry characteristic of the solution to Schrödinger's wave equation, and to that extent crystallization is explained by the atomic theory. Nevertheless this process retains a statistical and - one might almost say - historical element which cannot be further reduced: even when the state of the liquid is completely known before crystallization, the shape of the crystal is not determined by the laws of quantum mechanics. The formation of regular shapes is just far more probable than that of a shapeless lump. But the ultimate shape owes its genesis partly to an element of chance which in principle cannot be analysed further.
Werner Heisenberg
The possibility and significance of fractional angular momentum is discussed, and some simple physical realizations of it are mentioned. This leads naturally to consideration of the possibility of fractional quantum statistics, which is seen to be a possibility inherent in the kinematics of 2+1 dimensional quantum mechanics. Both sorts of fractionalization are intimately related to theories, and the classic considerations of Aharonov and Bohm on the significance of the vector potential in quantum mechanics. The meaning and importance of discrete gauge invariance in continuum theories is pointed out. Fractional statistics is shown to have a simple dynamical realization in the dynamics of charge-flux tube composites. Fractional statistics is shown to occur very naturally in the most geometrical quantum field theories in 2+1 dimensions, that is in the nonlinear sigma model and in quantum electrodynamics.
Frank Wilczek
The Prime Minister spent a lot of time painting to you a lurid picture of what would happen under a Labour Government in pursuit of what he called a Continental conception. He has forgotten that Socialist theory was developed by Robert Owen in Britain long before Karl Marx. He has forgotten that Australia, New Zealand, whose peoples have played so great a part in the war, and the Scandinavian countries have had Socialist Governments for years, to the great benefit of their peoples, with none of those dreadful consequences...When he talks of the danger of a secret police...he forgets that these things were actually experienced in this country only under the Tory Government of Lord Liverpool in the years of repression when the British people who had saved Europe from Napoleon were suffering deep distress. He has forgotten many things, including, when he talks of the danger of Labour mismanaging finance, his own disastrous record at the Exchequer over the gold standard.
Clement Attlee