Sierens, T. (2017). Quantum critical responses via holographic models and conformal perturbation theory. Perimeter Institute. https://pirsa.org/17060018

MLA

Sierens, Todd. Quantum critical responses via holographic models and conformal perturbation theory. Perimeter Institute, Jun. 01, 2017, https://pirsa.org/17060018

BibTex

@misc{ pirsa_PIRSA:17060018,
doi = {10.48660/17060018},
url = {https://pirsa.org/17060018},
author = {Sierens, Todd},
keywords = {Other},
language = {en},
title = {Quantum critical responses via holographic models and conformal perturbation theory},
publisher = {Perimeter Institute},
year = {2017},
month = {jun},
note = {PIRSA:17060018 see, \url{https://pirsa.org}}
}

We investigate response functions near quantum critical points, allowing for finite temperature and a mild deformation by a relevant scalar. When the quantum critical point is described by a conformal field theory, we use conformal perturbation theory and holography to determine the two leading corrections to the scalar two-point function and to the conductivity. We build a bridge between the couplings fixed by conformal symmetry with the interaction couplings in the gravity theory. We construct a minimal holographic model that allows us to numerically obtain the response functions at all frequencies, independently confirming the corrections to the high-frequency response functions. In addition to probing the physics of the ultraviolet, the holographic model probes the physics of the infrared giving us qualitative insight into new physics scalings.