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Related papers: Weyl Anomaly and Initial Singularity Crossing

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We discuss the cosmological evolution of the Weyl conformal geometry and its associated Weyl quadratic gravity. The Einstein gravity (with a positive cosmological constant) is recovered in the spontaneously broken phase of Weyl gravity;…

General Relativity and Quantum Cosmology · Physics 2022-06-24 D. M. Ghilencea , T. Harko

We discuss an enhancement of the Brown-Henneaux boundary conditions in three-dimensional AdS General Relativity to encompass Weyl transformations of the boundary metric. The resulting asymptotic symmetry algebra, after a field-dependent…

High Energy Physics - Theory · Physics 2021-10-13 Francesco Alessio , Glenn Barnich , Luca Ciambelli , Pujian Mao , Romain Ruzziconi

We determine the leading order fall-off behaviour of the Weyl tensor in higher dimensional Einstein spacetimes (with and without a cosmological constant) as one approaches infinity along a congruence of null geodesics. The null congruence…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Marcello Ortaggio , Alena Pravdová

We present a theory of the anomalous Hall effect in a topological Weyl superconductor with broken time reversal symmetry. Specifically, we consider a ferromagnetic Weyl metal with two Weyl nodes of opposite chirality near the Fermi energy.…

Superconductivity · Physics 2016-08-24 G. Bednik , A. A. Zyuzin , A. A. Burkov

We study homogeneous and isotropic cosmologies in a Weyl spacetime. It is shown that in Weyl integrable spacetime, the corresponding scalar field may act as a phantom field. In this circumstance the Weyl field gives rise to a late…

General Relativity and Quantum Cosmology · Physics 2015-06-12 John Miritzis

The Weyl semimetal surface is modeled by applying the Bogolyubov boundary conditions, in which the quasiparticles have an infinite Dirac mass outside the semimetal. For a Weyl semimetal shaped as a slab of finite thickness, we derive an…

Strongly Correlated Electrons · Physics 2014-09-19 E. V. Gorbar , V. A. Miransky , I. A. Shovkovy , P. O. Sukhachov

The first part of this thesis focuses on the Weyl-covariant nature of holography. We generalize the Fefferman-Graham ambient construction for conformal geometry to a corresponding construction for Weyl geometry. Through the Weyl-ambient…

High Energy Physics - Theory · Physics 2025-11-27 Weizhen Jia

We show that a class of finite quantum non-local gravitational theories is conformally invariant at classical as well as at quantum level. This is actually a range of conformal anomaly-free theories in the spontaneously broken phase of the…

High Energy Physics - Theory · Physics 2018-09-03 Leonardo Modesto , Leslaw Rachwal

The initial singularity is the most troubling feature of the standard cosmology, which quantum effects are hoped to resolve. In this paper, we study quantum cosmology with conformal (Weyl) invariant matter. We show it is natural to extend…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Steffen Gielen , Neil Turok

We discuss the generalization of the local renormalization group approach to theories in which Weyl symmetry is gauged. These theories naturally correspond to scale invariant - rather than conformal invariant - models in the flat space…

High Energy Physics - Theory · Physics 2023-12-04 Omar Zanusso

One of the more popular objections towards shape dynamics is the suspicion that anomalies in the spatial Weyl symmetry will arise upon quantization. The purpose of this short paper is to establish the tools required for an investigation of…

General Relativity and Quantum Cosmology · Physics 2013-11-28 Henrique Gomes

We predict a nonlinear Hall effect in certain Weyl semimetals with broken inversion symmetry. When the energy dispersions about pairs of Weyl nodes are skewed -- the Weyl cones are "tilted" -- the concerted actions of the anomalous velocity…

Mesoscale and Nanoscale Physics · Physics 2021-01-19 Rui-Hao Li , Olle G. Heinonen , Anton A. Burkov , Steven S. -L. Zhang

Weyl semimetals are gapless quasi-topological materials with a set of isolated nodal points forming their Fermi surface. They manifest their quasi-topological character in a series of topological electromagnetic responses including the…

Mesoscale and Nanoscale Physics · Physics 2016-02-05 Hassan Shapourian , Taylor L. Hughes

We study the particle spectrum and the unitarity of the generic n-dimensional Weyl-invariant quadratic curvature gravity theories around their (anti-)de Sitter [(A)dS] and flat vacua. Weyl symmetry is spontaneously broken in (A)dS and…

High Energy Physics - Theory · Physics 2012-03-13 M. Reza Tanhayi , Suat Dengiz , Bayram Tekin

Penrose's 1979 Weyl curvature hypothesis (WCH) \cite{WCH} assumes that the universe began at a very low gravitational entropy state, corresponding to zero Weyl curvature, namely, the FLRW universe. This is a simple assumption with…

General Relativity and Quantum Cosmology · Physics 2021-11-09 Bei-Lok Hu

The \gamma-trace anomaly of supersymmetry current in a supersymmetric gauge theory shares a superconformal anomaly multiplet with the chiral R-symmetry anomaly and the Weyl anomaly, and its holographic reproduction is a valuable test to the…

High Energy Physics - Theory · Physics 2015-06-26 M. Chaichian , W. F. Chen

Non-Hermiticity in Weyl Hamiltonian leads to the realization of Weyl exceptional rings and flat bands inside the Weyl exceptional rings. Recently, the platform of non-Hermitian physics is extended to many-body or disordered systems where…

Mesoscale and Nanoscale Physics · Physics 2019-12-18 Taiki Matsushita , Yuki Nagai , Satoshi Fujimoto

The ferromagnetic Weyl semimetals, such as Co3Sn2S2, feature pairs of Weyl points characterized by the opposite chiralities.We model this type of semimetals by the inversion symmetry protected and the time reversal symmetry broken Bloch…

Mesoscale and Nanoscale Physics · Physics 2023-09-20 Udai Prakash Tyagi , Partha Goswami

We show that Weyl semimetals exhibit a mixed axial-torsional anomaly in the presence of axial torsion, a concept exclusive of these materials with no known natural fundamental interpretation in terms of the geometry of spacetime. This…

Mesoscale and Nanoscale Physics · Physics 2019-02-13 Yago Ferreiros , Yaron Kedem , Emil J. Bergholtz , Jens H. Bardarson

Weyl semimetals are well-known for hosting topologically protected linear band crossings, serving as the analog of the relativistic Weyl Fermions in the condensed matter context. Such analogy persists deeply, allowing the existence of the…

Mesoscale and Nanoscale Physics · Physics 2024-02-15 Yang Gao