classical field theory
negare-ye klâsik-e meydân
Fr.: théorie classique des champs
The theory that studies distributions of → energy, → matter, and other physical quantities under circumstances where their discrete nature is unimportant. Classical field theory traditionally includes → Newtonian mechanics, Maxwell's → electromagnetic theory, and Einstein's theory of → general relativity. The main scope of classical field theory is to construct the mathematical description of → dynamical systems with an infinite number of degrees of freedom. The word "classical" is used in contrast to those field theories that incorporate → quantum mechanics (→ quantum field theory). Classical field theories are usually categorized as → non-relativistic and → relativistic.
Fr.: théorie des champs
1) A theory which uses the concept of → field
to describe physical phenomena. It consists of two types:
→ classical field theory
and → quantum field theory.
negare-ye meydân-e gerâneši (#)
Fr.: théorie de champ gravitationnel
A theory that treats gravity as a field rather than a force acting at a distance.
quantum field theory
negare-ye kuântomi-ye meydân
Fr.: théorie quantique des champs
The quantum mechanical theory based on the assumption that the interactions between particles and fields are mediated by messenger particles. Accordingly, particles are → quanta of a field, just s photons are quanta of light. All fields display a granular structure in interaction. QFT is the framework in which quantum mechanics and → special relativity are successfully reconciled (→ Dirac equation). It forms the basis of today's particle physics.