Fermat's principle
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Wikidata facts
- Instance of
- variational principle
- Named after
- Pierre de Fermat
Show 3 more facts
- name in kana
- フェルマーのげんり
- inception
- 1662-01-01
- described by source
- Armenian Soviet Encyclopedia
Sources (1)
via Wikidata · CC0
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Encyclopedic overview
Fig. 1: Fermat's principle in the case of refraction of light at a flat surface between (say) air and water. Given an object-point A in the air, and an observation point B in the water, the refraction point P is that which minimizes the time taken by the light to travel the path APB. Seeking the required value of x shows that the angles α and β satisfy Snell's law.
Fermat's principle, also known as the principle of least time, is the link between ray optics and wave optics. Fermat's principle states that the path taken by a ray between two given points is the path that can be traveled in the least time.
Excerpted from Wikipedia’s “Fermat's principle” article, available under the CC BY-SA 4.0 licence.