Projective fixed points for non-Fermi liquids: A case study of the Ising-nematic quantum critical metal

Fixed points of the renormalization group flow play a crucial role in classifying phases of matter. In metals, these fixed points are defined only projectively due to the indefinitely increasing Fermi momentum under scale transformations. Here, the authors study the physical implications of the projective nature of metallic fixed points and chart the space of projective fixed points for Ising-nematic quantum critical metals. Their universality classes are characterized by a nontunable universal forward interaction and intrinsic superconducting fluctuations.