The term modern physics refers to the post-Newtonian conception of physics. The term implies that classical descriptions of phenomena are lacking, and that an accurate, "modern", description of reality requires theories to incorporate elements of quantum mechanics or Einsteinian relativity, or both. In general, the term is used to refer to any branch of physics either developed in the early 20th century and onwards, or branches greatly influenced by early 20th century physics.
Modern physics often involves extreme conditions; quantum effects usually involve distances comparable to atoms (roughly 10−9 m), while relativistic effects usually involve velocities comparable to the speed of light (roughly 108 m/s). Small velocities and large distances is usually the realm of classical mechanics.
Read more about Modern Physics: Overview, Hallmarks of Modern Physics
Famous quotes containing the words modern and/or physics:
“By bourgeoisie is meant the class of modern capitalists, owners of the means of social production and employers of wage labor. By proletariat, the class of modern wage laborers who, having no means of production of their own, are reduced to selling their labor power in order to live.”
—Friedrich Engels (1820–1895)
“The fundamental laws of physics do not describe true facts about reality. Rendered as descriptions of facts, they are false; amended to be true, they lose their explanatory force.”
—Nancy Cartwright (b. 1945)