Boundary Conformal Field Theory and a Boundary Central Charge

We consider the structure of current and stress tensor two-point functions in conformal field theory with a boundary. The main result of this paper is a relation between a boundary central charge and the coefficient of a displacement operator correlation function in the boundary limit. The boundary central charge under consideration is the coefficient of the product of the extrinsic curvature and the Weyl curvature in the conformal anomaly. Along the way, we describe several auxiliary results. Three of the more notable are as follows: (1) we give the bulk and boundary conformal blocks for the current two-point function; (2) we show that the structure of these current and stress tensor two-point functions is essentially universal for all free theories; (3) we introduce a class of interacting conformal field theories with boundary degrees of freedom, where the interactions are confined to the boundary. The most interesting example we consider can be thought of as the infrared fixed point of graphene. This particular interacting conformal model in four dimensions provides a counterexample of a previously conjectured relation between a boundary central charge and a bulk central charge. The model also demonstrates that the boundary central charge can change in response to marginal deformations.Comment: 75 pages, 4 figures; v2: references added. v3: comments on anomalous dimension and references added. v4: minor corrections, published versio

Interface Conformal Anomalies

We consider two $d \geq 2$ conformal field theories (CFTs) glued together along a codimension one conformal interface. The conformal anomaly of such a system contains both bulk and interface contributions. In a curved-space setup, we compute the heat kernel coefficients and interface central charges in free theories. The results are consistent with the known boundary CFT data via the folding trick. In $d=4$, two interface invariants generally allowed as anomalies turn out to have vanishing interface charges. These missing invariants are constructed from components with odd parity with respect to flipping the orientation of the defect. We conjecture that all invariants constructed from components with odd parity may have vanishing coefficient for symmetric interfaces, even in the case of interacting interface CFT.Comment: 14 pp; v2: clarifications added, introduction expande

Now is the envy of all of the dead: an introduction to Don Hertzfeldt, the animator

This thesis is a primer on the experimental independent animator Don Hertzfeldt, whose filmography—described by one critic as “a singular universe of stick figures in crisis”—has for more than two decades been engaging some of the larger questions of post-millennial existence, particularly with regard to consciousness, temporality, and death. First, I will briefly introduce who Hertzfeldt is as an auteur (where he comes from, where his primary interests lie, and what his impact has been); second, I will provide an overview of the historical context in which his oeuvre should be placed (i.e. the history of animation and of experimental cinema); third, I will closely analyze his work, examining questions of style and narrative, starting from his student films and continuing to his more recent films; and fourth, I will explore some of the philosophical implications of recurring Hertzfeldtian motifs and themes (particularly with regard to consciousness, temporality, and death) before concluding