Princeton University High Energy Theory Seminar

Abstract: We introduce an effective field theory (EFT) for conformal impurities, constructed from pairs of transversely displaced defects. This EFT captures the universal signature of an impurity on heavy local operators. In the case of conformal boundaries, we show that it leads to universal formulas for boundary structure constants at large scaling dimensions. We also show how the familiar thermal EFT appears as a special case of this EFT with distinguished conformal boundaries. For general conformal defects, we further derive non-positivity and convexity-like constraints on the Casimir energy, which controls the leading EFT coefficient.