# Quantum field theory

Path integral | S Matrix | Quantum electrodynamics# Theory of relativity

Special theory of relativity | General theory of relativity

# Algebra for dummies

Algebra (from Arabic "al-jabr", literally meaning "reunion of broken parts"[1]) is one of the broad parts of mathematics, together with number theory, geometry and analysis. In its most general form, algebra is the study of mathematical symbols and the rules for manipulating these symbols;[2] it is a unifying thread of almost all of mathematics. It includes everything from elementary equation solving to the study of abstractions such as groups, rings, and fields. The more basic parts of algebra are called elementary algebra; the more abstract parts are called abstract algebra or modern algebra. Elementary algebra is generally considered to be essential for any study of mathematics, science, or engineering, as well as such applications as medicine and economics. Abstract algebra is a major area in advanced mathematics, studied primarily by professional mathematicians.

A typical algebraic equation contains variables and termsone or more v values of the variable are usually solutions to algebraic equation. Algebra was first combined with geometry by Rene Descates to study coordinate geometry. This was a revolution in mathematics and science. Coordinates are levels for points in two or more dimensional space.