physics
Physics is the branch of science concerned with the study of matter and energy. Physics seeks to identify and explain their many forms and relationships. Modern physics recognizes four basic forces in nature: gravitation, which was first adequately described by Isaac Newton; the electromagnetic force, codified in the 19th century by Maxwell's equations; the weak nuclear force, which is responsible for the decay of some subatomic particles; and the strong nuclear force, which binds together atomic nuclei.
Physics rests on six fundamental theories:
• Newtonian mechanics
• thermodynamics
• electromagnetism
• statistical mechanics
• relativity
• quantum mechanics
Branches of physics include
• particle physics
• geophysics
• biophysics
• astrophysics
• atomic and nuclear physics