# Theoretical physics Reference Libraries

Classical and Quantum Gravity is a peer-reviewed journal published by IOP Science. As of May 2012, the editor-in-chief is Clifford M Will (Washington University, St. Louis). The journal covers all aspects of gravitational physics and the theory of space-time. It scope includes: Classical general relativity, Applications of relativity, Experimental gravitation, Cosmology and the early...

Physics is the scientific study of matter and its motion through space/time and its derivitives, including energy and force. It is generally the analysis of nature and is conducted to help us understand how the universe behaves. Physics comes from the Greek word physis, meaning "nature". It is among the oldest academic disciplines, and perhaps the oldest pertaining to astronomy. Physics has...

String Theory -- A string theory is a physical model whose fundamental building blocks are extended objects (strings, membranes and higher-dimensional objects) rather than points. String theories are able to avoid problems, such as infinite energy density, associated with the presence of mathematical points in a physical theory. The term 'string theory' properly refers to both the 26...

Spacetime -- In special relativity and general relativity, time and three-dimensional space are treated together as a single four-dimensional manifold called spacetime (alternatively, space-time; see below). A point in spacetime may be referred to as an event. Each event has four coordinates (t, x, y, z). Just as the x, y, z coordinates of a point depend on the axes one is using, so...

- A person in a secondary role, specifically the second most important character (after the protagonist).