Unified field theory

In physics, a Unified Field Theory (UFT) or “Theory of Everything” is a type of field theory that allows all fundamental forces of nature, including gravity, and all elementary particles to be written in terms of a single physical field.^[1][2] According to quantum field theory, particles are themselves the quanta of fields. Different fields in physics include vector fields such as the electromagnetic field, spinor fields whose quanta are fermionic particles such as electrons, and tensor fields such as the metric tensor field that describes the shape of spacetime and gives rise to gravitation in general relativity. Unified field theories attempt to organize these fields into a single mathematical structure.

For over a century, the unified field theory has remained an open line of research. The term was coined by Albert Einstein, who attempted to unify his general theory of relativity with electromagnetism.^[3] Einstein attempted to create a classical unified field theory. Among other difficulties, this required a new explanation of particles as singularities or solitons instead of field quanta. Later attempts to unify general relativity with other forces incorporate quantum mechanics. The concept of a "Theory of Everything"^[4] or Grand Unified Theory^[5] are closely related to unified field theory. A theory of everything attempts to create a complete picture of all events in nature. Grand Unified Theories do not attempt to include the gravitational force and can therefore operate entirely within quantum field theory. The goal of a unified field theory has led to significant progress in theoretical physics.^[6]