RG boundaries and interfaces in Ising field theory

Abstract

Perturbing a CFT by a relevant operator on a half space and letting the perturbation flow to the far infrared we obtain an RG interface between the UV and IR CFTs. If the IR CFT is trivial we obtain an RG boundary condition. The space of massive perturbations thus breaks up into regions labelled by conformal boundary conditions of the UV fixed point. For the 2D critical Ising model perturbed by a generic relevant operator we find the assignment of RG boundary conditions to all flows. We use some analytic results but mostly rely on TCSA and TFFSA numerical techniques. We investigate real as well as imaginary values of the magnetic field and, in particular, the RG trajectory that ends at the Yang-Lee CFT. We argue that the RG interface in the latter case does not approach a single conformal interface but rather exhibits oscillatory non-convergent behaviour.

40 pages, many pictures; v.2 one reference and two comments added; v.3 minor corrections, references added

References in corpus (6)

• Fusion of conformal interfaces
• Hamiltonian truncation approach to quenches in the Ising field theory
• Defects and Bulk Perturbations of Boundary Landau-Ginzburg Orbifolds
• The renormalisation group for the truncated conformal space approach on the cylinder
• Excited state TBA and renormalized TCSA in the scaling Potts model
• Unitary Networks from the Exact Renormalization of Wave Functionals

Cited by in corpus (13)

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• Universal entanglement signatures of interface conformal field theories
• Entanglement Action for the Real-Space Entanglement Spectra of Composite Fermion Wave Functions
• Scaling of the Formation Probabilities and Universal Boundary Entropies in the Quantum XY Spin Chain
• Critical Ising Model with Boundary Magnetic Field: RG Interface and Effective Hamiltonians
• On asymptotic behaviour in truncated conformal space approach
• TCSA and the finite volume boundary state
• Crosscap states and duality of Ising field theory in two dimensions
• Boundary Criticality of Complex Conformal Field Theory: A Case Study in the Non-Hermitian 5-State Potts Model
• Efficient Representation of Gaussian Fermionic Pure States in Non-Computational Bases