Low’s soft-photon theorem
E1015933
Low’s soft-photon theorem is a fundamental result in quantum electrodynamics that precisely characterizes how amplitudes behave when low-energy (soft) photons are emitted in particle interactions.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Low’s soft-photon theorem canonical | 1 |
Statements (45)
| Predicate | Object |
|---|---|
| instanceOf |
soft-theorem
ⓘ
theorem in quantum electrodynamics ⓘ |
| appliesIn | perturbative QED ⓘ |
| appliesTo |
emission of low-energy photons
ⓘ
processes with external charged particles ⓘ scattering amplitudes ⓘ |
| assumes |
on-shell external particles
ⓘ
photon mass equal to zero ⓘ |
| basedOn |
Lorentz invariance
ⓘ
analyticity of scattering amplitudes ⓘ gauge invariance ⓘ |
| characterizes |
factorization of soft-photon emission from hard scattering
ⓘ
universal infrared behavior of amplitudes ⓘ |
| concerns |
emission of arbitrarily many soft photons at leading order in energy
ⓘ
soft-photon limit of QED amplitudes ⓘ |
| describes | behavior of scattering amplitudes with soft-photon emission ⓘ |
| domain |
high-energy physics
ⓘ
particle physics ⓘ |
| ensures | model-independent structure of leading infrared behavior in QED ⓘ |
| field |
quantum electrodynamics
ⓘ
quantum field theory ⓘ |
| framework | S-matrix theory NERFINISHED ⓘ |
| hasConsequence |
cancellation patterns between real and virtual infrared divergences
ⓘ
constraints on radiative corrections in QED processes ⓘ |
| implies |
leading soft-photon factor depends only on external charged particle momenta and charges
ⓘ
subleading soft-photon terms are constrained by gauge invariance and kinematics ⓘ |
| influenced |
development of modern soft-theorem program
ⓘ
infrared-safe observable construction in gauge theories ⓘ |
| involvesLimit | photon energy going to zero ⓘ |
| predicts |
subleading corrections in photon energy expansion
ⓘ
universal leading 1/ω behavior of soft-photon emission amplitude ⓘ |
| relatedTo |
Bloch–Nordsieck mechanism
NERFINISHED
ⓘ
Ward identities NERFINISHED ⓘ Weinberg’s soft-graviton theorem NERFINISHED ⓘ infrared divergences ⓘ soft-collinear factorization ⓘ |
| relates | amplitudes with and without an additional soft photon ⓘ |
| softObject | photon ⓘ |
| states | soft-photon emission amplitude factorizes into universal soft factor times hard amplitude ⓘ |
| typeOfSoftTheorem |
leading soft-photon theorem
ⓘ
subleading soft-photon theorem ONNER ⓘ |
| usedFor |
precision calculations in scattering processes involving photons
ⓘ
soft-photon resummation techniques ⓘ systematic treatment of infrared divergences in QED ⓘ |
| validIn | low-photon-energy regime ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.