Séminaire de Physique Théorique

Conformal Boundary Conditions, Cardy's Variational Ansatz and Phase Structure of 2D QFTs

by Anatoly Konechny (Heriot-Watt University & IHES)

Amphithéâtre Léon Motchane (IHES)

Amphithéâtre Léon Motchane


Le Bois-Marie, 35, route de Chartres 91440 Bures-sur-Yvette

We will consider perturbations of 2D CFTs by multiple relevant operators. The massive phases of such perturbations can be labeled by conformal boundary conditions. Cardy's variational ansatz approximates the vacuum state of the perturbed theory by a smeared conformal boundary state. In this talk we will discuss the limitations and propose generalisations of this ansatz using both analytic and numerical insights based on TCSA. In particular we analyse the stability of Cardy's ansatz states with respect to boundary relevant perturbations using  bulk-boundary OPE coefficients. We show that certain transitions  between the massive phases arise from a pair of boundary RG flows.  The RG flows start from the conformal boundary on the transition surface and end on those that lie on the two sides of it. As an example we work out the details of the phase diagram for the Ising field theory and for the tricritical Ising model  perturbed by the leading thermal and magnetic fields. Based on arXiv:2306.13719.


Pour être informé des prochains séminaires vous pouvez vous abonner à la liste de diffusion en écrivant un mail à sympa@listes.math.cnrs.fr avec comme sujet: "subscribe seminaire_physique PRENOM NOM"
(indiquez vos propres prénom et nom) et laissez le corps du message vide.

Organized by

Slava Rychkov