Subleading soft photons and large gauge transformations
Resumen:
Lysov, Pasterski and Strominger have shown how Low’s subleading soft photon theorem can be understood as Ward identities of new symmetries of massless QED. In this paper we offer a different perspective and show that there exists a class of large U(1) gauge transformations such that (i) the associated (electric and magnetic) charges can be computed from first principles, (ii) their Ward identities are equivalent to Low’s theorem. Our framework paves the way to analyze the sub-subleading theorem in gravity in terms of Ward identities associated to large diffeomorphisms.
2016 | |
Gauge symmetry Global symmetries Scattering amplitudes |
|
Inglés | |
Universidad de la República | |
COLIBRI | |
https://hdl.handle.net/20.500.12008/22036 | |
Acceso abierto | |
Licencia Creative Commons Atribución (CC –BY 4.0) |
Sumario: | Lysov, Pasterski and Strominger have shown how Low’s subleading soft photon theorem can be understood as Ward identities of new symmetries of massless QED. In this paper we offer a different perspective and show that there exists a class of large U(1) gauge transformations such that (i) the associated (electric and magnetic) charges can be computed from first principles, (ii) their Ward identities are equivalent to Low’s theorem. Our framework paves the way to analyze the sub-subleading theorem in gravity in terms of Ward identities associated to large diffeomorphisms. |
---|