2,272 research outputs found
Chiral Scale and Conformal Invariance in 2D Quantum Field Theory
It is well known that a local, unitary Poincare-invariant 2D QFT with a
global scaling symmetry and a discrete non-negative spectrum of scaling
dimensions necessarily has both a left and a right local conformal symmetry. In
this paper we consider a chiral situation beginning with only a left global
scaling symmetry and do not assume Lorentz invariance. We find that a left
conformal symmetry is still implied, while right translations are enhanced
either to a right conformal symmetry or a left U(1) Kac-Moody symmetry.Comment: 6 pages, no figures. v2: reference added, minor typos correcte
Einstein gravity from ANEC correlators
We study correlation functions with multiple averaged null energy (ANEC)
operators in conformal field theories. For large CFTs with a large gap to
higher spin operators, we show that the OPE between a local operator and the
ANEC can be recast as a particularly simple differential operator acting on the
local operator. This operator is simple enough that we can resum it and obtain
the finite distance OPE. Under the large - large gap assumptions, the
vanishing of the commutator of ANEC operators tightly constrains the OPE
coefficients of the theory. An important example of this phenomenon is the
conclusion that in . This implies that the bulk dual of such a CFT
is semi-classical Einstein-gravity with minimally coupled matter.Comment: 32 pages + appendices, 6 figures; v2:typos corrected and a comment
added in introductio
Warped Weyl fermion partition functions
Warped conformal field theories (WCFTs) are a novel class of non-relativistic
theories. A simple, yet non-trivial, example of such theory is a massive Weyl
fermion in -dimensions, which we study in detail. We derive general
properties of the spectrum and modular properties of partition functions of
WCFTs. The periodic (Ramond) sector of this fermionic system is non-trivial,
and we build two novel partition functions for this sector which have no
counterpart in a CFT. The thermodynamical properties of WCFTs are revisited
in the canonical and micro-canonical ensemble.Comment: 41 page
Generalized Lifshitz-Kosevich scaling at quantum criticality from the holographic correspondence
We characterize quantum oscillations in the magnetic susceptibility of a
quantum critical non-Fermi liquid. The computation is performed in a strongly
interacting regime using the nonperturbative holographic correspondence. The
temperature dependence of the amplitude of the oscillations is shown to depend
on a critical exponent nu. For general nu the temperature scaling is distinct
from the textbook Lifshitz-Kosevich formula. At the `marginal' value nu = 1/2,
the Lifshitz-Kosevich formula is recovered despite strong interactions. As a
by-product of our analysis we present a formalism for computing the amplitude
of quantum oscillations for general fermionic theories very efficiently.Comment: 18 pages, pdftex, 1 figure. v2: figure and few comments adde
De Sitter Horizons & Holographic Liquids
We explore asymptotically AdS solutions of a particular two-dimensional
dilaton-gravity theory. In the deep interior, these solutions flow to the
cosmological horizon of dS. We calculate various matter perturbations at
the linearised and non-linear level. We consider both Euclidean and Lorentzian
perturbations. The results can be used to characterise the features of a
putative dual quantum mechanics. The chaotic nature of the de Sitter horizon is
assessed through the soft mode action at the AdS boundary, as well as the
behaviour of shockwave type solutions.Comment: 37 pages, 7 figures; v2: minor corrections; v3: updated references,
new Penrose diagram and minor comments added to match published version; v4:
Acknowledgement adde
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