English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In the on-shell formalism (mostly used in perturbative quantum field theory)the entries of the time ordered product T are on-shell fields (i.e. the basicfields satisfy the free field equations). With that, (multi)linearity of T isincompatible with the Action Ward identity. This can be circumvented by usingthe off-shell formalism in which the entries of T are off-shell fields. Torelate on- and off-shell formalism correctly, a map sigma from on-shell fieldsto off-shell fields was introduced axiomatically by Duetsch and Fredenhagen. Inthat paper it was shown that, in the case of one real scalar field in N=4dimensional Minkowski space, these axioms have a unique solution. However, thissolution was given there only recursively. We solve this recurrence relationand give a fully explicit expression for sigma in the cases of the scalar,Dirac and gauge fields for arbitrary values of the dimension N.

Relating on-shell and off-shell formalism in perturbative quantum field theory