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Fermat's principle (Topic)

Fermat's Principle

Initially conceived in optics, Fermat's principle was stated as the principle of least time for traveling light waves, that is the path or paths taken between two points by light which can be traversed in the least time; in an Euclidean space or a flat Minkowski space, this is the straight line defined by a single ray of light. This can be thought as the trajectory of an emitted photon traveling at the universal maximum speed $ c$ in vacuum. In a Riemannian or Minkowski spacetime this corresponds to the surface of a light cone.

In general relativity, however, a point particle path is a geodesic curve in a Riemannian space that can be curved, for example, by the presence of intense gravitational fields. One such effect was observed and reported by modern astrophysicists and is called gravitational lensing.

Minimum Action Principles in Electromagnetism and Quantum Theories



"Fermat's principle" is owned by bci1.
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See Also: Heron's principle

Other names:  principle of minimum action
Also defines:  gravitational lensing
Keywords:  Fermat's principle in optics and quantum theories, gravitational lensing, Euclidean space, Riemannian space

Cross-references: geodesic, spacetime, speed
There are 2 references to this object.

This is version 8 of Fermat's principle, born on 2009-02-13, modified 2009-03-03.
Object id is 520, canonical name is FermatsPrinciple.
Accessed 337 times total.

Classification:
Physics Classification00. (GENERAL)
 02. (Mathematical methods in physics)
 42.15.-i (Geometrical optics)
 02.40.Dr (Euclidean and projective geometries)
 03. (Quantum mechanics, field theories, and special relativity )
 03.65.Fd (Algebraic methods )

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