Word.ws English Dictionary

Furry's theorem

Furry's theorem proper noun: in quantum electrodynamics, a theorem stating that if a Feynman diagram consists of a closed loop of fermion lines with an odd number of vertices, its contribution to the amplitude vanishes (and therefore a single photon cannot arise from the vacuum or be absorbed by it).

Proper noun

Furry's theorem

  1. In quantum electrodynamics, a theorem stating that if a Feynman diagram consists of a closed loop of fermion lines with an odd number of vertices, its contribution to the amplitude vanishes (and therefore a single photon cannot arise from the vacuum or be absorbed by it).

Origin of Furry's theorem

The theorem was derived by Wendell H. Furry in 1937.

Questions about Furry's theorem

What does Furry's theorem mean?
Furry's theorem means in quantum electrodynamics, a theorem stating that if a Feynman diagram consists of a closed loop of fermion lines with an odd number of vertices, its contribution to the amplitude vanishes (and therefore a single photon cannot arise from the vacuum or be absorbed by it).
What part of speech is Furry's theorem?
Furry's theorem is a proper noun.

Words near Furry's theorem in the dictionary

  1. furry lobsters
  2. furry muff
  3. furry number
  4. furry triangle
  5. furry triangles
  6. Furry's theorem
  7. furrybait
  8. furrydom
  9. furryism
  10. Furrys
  11. furrysuit

Source and license

Adapted from Wiktionary: Furry's theorem (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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