Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Properties of RG interfaces for 2D boundary flows   We consider RG interfaces for boundary RG flows in two-dimensional QFTs. Such
interfaces are particular boundary condition changing operators linking the UV
and IR conformal boundary conditions. We refer to them as RG operators. In this
paper we study their general properties putting forward a number of
conjectures. We conjecture that an RG operator is always a conformal primary
such that the OPE of this operator with its conjugate must contain the
perturbing UV operator when taken in one order and the leading irrelevant
operator (when it exists) along which the flow enters the IR fixed point, when
taken in the other order. We support our conjectures by perturbative
calculations for flows between nearby fixed points, by a non-perturbative
variational method inspired by the variational method proposed by J.~Cardy for
massive RG flows, and by numerical results obtained using boundary TCSA. The
variational method has a merit of its own as it can be used as a first
approximation in charting the global structure of the space of boundary RG
flows. We also discuss the role of the RG operators in the transport of states
and local operators. Some of our considerations can be generalised to
two-dimensional bulk flows, clarifying some conceptual issues related to the RG
interface put forward by D.~Gaiotto for bulk $\phi_{1,3}$ flows.

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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg
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The categories of this paper are: ao-sci
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The categories of this paper are: stat
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
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The categories of this paper are: physics
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The categories of this paper are: funct-an
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
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The categories of this paper are: alg-geom