Unified field theory

In physics, unified field theory is an attempt to unify all the fundamental forces and the interactions between elementary particles into a single theoretical framework. The term was coined by Einstein who attempted to reconcile the general theory of relativity with electromagnetism in a single field theory. His quest proved elusive and a unified field theory, sometimes grandiosely referred to as the Theory of Everything (TOE, for short), has remained the holy grail for physicists, the long-sought theory which would explain the nature and behavior of all matter.

Related Topics:
Physics - Elementary particle - Einstein - Electromagnetism - Field theory - Theory of Everything

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In physics, the forces between objects can be described as mediated by fields. Current theory says that at subatomic distances, these fields are replaced by quantum fields interacting according to the laws of quantum mechanics. Alternatively, using the particle-wave duality of quantum mechanics, fields can be described in terms of exchange particles that transfer momentum and energy between objects. Crudely speaking, objects interact as they emit and absorb exchanged particles, in effect playing a subatomic game of "catch". The essential belief of a unified field theory is that the four fundamental forces (see below) as well as all matter are simply different manifestations of a single fundamental field.

Related Topics:
Subatomic - Quantum mechanic - Exchange particle

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A unified field theory aims to reconcile the four fundamental forces (or fields) of nature, namely:

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• Strong force: Force responsible for holding quarks together to form neutrons and protons, and holding neutrons and protons together to form nuclei. The exchange particles that mediate this force are gluons.
• Electromagnetic force: It is the familiar force that acts on electrically charged particle. The photon is the exchange particle for this force.
• Weak force: Responsible for radioactivity, it is a repulsive short-range interaction that acts on electrons, neutrinos and quarks. It is governed by the W boson.
• Gravitational force: A long-range attractive force that acts on all particles. The exchange particles have been postulated and named gravitons.
 
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