Journal of High Energy Physics (Feb 2023)

A dispersion relation for defect CFT

  • Julien Barrat,
  • Aleix Gimenez-Grau,
  • Pedro Liendo

DOI
https://doi.org/10.1007/JHEP02(2023)255
Journal volume & issue
Vol. 2023, no. 2
pp. 1 – 32

Abstract

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Abstract We present a dispersion relation for defect CFT that reconstructs two-point functions in the presence of a defect as an integral of a single discontinuity. The main virtue of this formula is that it streamlines explicit bootstrap calculations, bypassing the resummation of conformal blocks. As applications we reproduce known results for monodromy defects in the epsilon-expansion, and present new results for the supersymmetric Wilson line at strong coupling in N $$ \mathcal{N} $$ = 4 SYM. In particular, we derive a new analytic formula for the highest R-symmetry channel of single-trace operators of arbitrary length.

Keywords