Journal of High Energy Physics (Mar 2022)

Bootstrapping boundary-localized interactions II. Minimal models at the boundary

  • Connor Behan,
  • Lorenzo Di Pietro,
  • Edoardo Lauria,
  • Balt C. van Rees

DOI
https://doi.org/10.1007/JHEP03(2022)146
Journal volume & issue
Vol. 2022, no. 3
pp. 1 – 40

Abstract

Read online

Abstract We provide evidence for the existence of non-trivial unitary conformal boundary conditions for a three-dimensional free scalar field, which can be obtained via a coupling to the m’th unitary diagonal minimal model. For large m we can demonstrate the existence of the fixed point perturbatively, and for smaller values we use the numerical conformal bootstrap to obtain a sharp kink that smoothly matches onto the perturbative predictions. The wider numerical analysis also yields universal bounds for the spectrum of any other boundary condition for the free scalar field. A second kink in these bounds hints at a second class of non-standard boundary conditions, as yet unidentified.

Keywords