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Atom in Modern Science
SECTION III
NEW PHYSICS
23
DUAL NATURE OF MATTER
As stated above, the planetary model showed that atoms, instead of being hard, indestructible and indivisible particles, consisted of vast regions of empty space, in which extremely small particles-electrons - moved around the nucleus, bound to it by electromagnetic forces. But, later development in Quantum physics established that even these particles were not solid objects of classical physics. They appear sometimes as particles, and sometimes as waves.
QUANTUM PHYSICS
The Quantum physics forced itself upon the scientific world at the beginning of this century with a discovery made in 1900 by Max Planck. He was trying to solve a specific problem, dealing with energy radiation. He wanted to know why objects glow bright and change colour when the temperature is increased (or decreased). Classical physics failed to give explanation to this simple phenomenon. Planck discovered that energy is not radiated (or absorbed) smoothly and continuously, but in spurts of specific amount or quanta1 (discrete packets). It was difficult to accept the concepts of the new theory, even after its precise and consistent mathematical formulation, because their implications were practically unbelievable.
In 1905, at the age of 26, Albert Einstein exploded upon the field of science with a force seldom exerted by a single scientist. He constructed the 'Theory of Relativity' in its complete form, entirely by himself. In the same year, he also declared a new way of studying the electromagnetic radiations which was to become the basis of Quantum Physics. It took several years' work by a
1. Planck himself was very unhappy with the implications of his discovery as he had no intention to destroy the foundation of the Newtonian Physics.
