English
Related papers

Related papers: Conformal pure radiation with parallel rays

200 papers

Given a flat vector bundle over a compact Riemannian manifold, Corlette and Donaldson proved that it admits harmonic metrics if and only if it is semi-simple. In this paper, we extend this equivalence to arbitrary vector bundles without any…

Differential Geometry · Mathematics 2023-04-24 Di Wu , Xi Zhang

In this paper we introduce, in the Riemannian setting, the notion of conformal Ricci soliton, which includes as particular cases Einstein manifolds, conformal Einstein manifolds and (generic and gradient) Ricci solitons. We provide here…

Differential Geometry · Mathematics 2016-08-09 Giovanni Catino , Paolo Mastrolia , Dario D. Monticelli , Marco Rigoli

In this paper, we study conformal submersions from Ricci solitons to Riemannian manifolds with non-trivial examples. First, we study some properties of the O'Neill tensor $A$ in the case of conformal submersion. We also find a necessary and…

Differential Geometry · Mathematics 2023-11-07 Kiran Meena , Akhilesh Yadav

The baryon-dark matter coincidence is a long-standing issue. Interestingly, the recent observations suggest the presence of dark radiation, which, if confirmed, would pose another coincidence problem of why the density of dark radiation is…

High Energy Physics - Phenomenology · Physics 2015-06-15 Tetsutaro Higaki , Kwang Sik Jeong , Fuminobu Takahashi

We introduce the concept of bi-conformal transformation, as a generalization of conformal ones, by allowing two orthogonal parts of a manifold with metric $\G$ to be scaled by different conformal factors. In particular, we study their…

Mathematical Physics · Physics 2016-08-16 Alfonso García-Parrado , José M. M. Senovilla

The difference tensor R.C-C.R of a semi-Riemannian manifold (M,g), dim M > 3, formed by its Riemannian-Christoffel curvature tensor R and the Weyl conformal curvature tensor C, under some assumptions, can be expressed as a linear…

In this paper, we have reintroduced a new approach to conformal geometry developed and presented in two previous papers, in which we show that all n-dimensional pseudo-Riemannian metrics are conformal to a flat n-dimensional manifold as…

Mathematical Physics · Physics 2012-12-20 A. C. V. V. de Siqueira

Conformally related metrics and Lagrangians are considered in the context of scalar-tensor gravity cosmology. After the discussion of the problem, we pose a lemma in which we show that the field equations of two conformally related…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Michael Tsamparlis , Andronikos Paliathanasis , Spyros Basilakos , Salvatore Capozziello

We analyze the relationship between $n$-dimensional conformal metrics and a certain class of partial differential equations (PDEs) that are in duality with the eikonal equation. In particular, we extend the Null Surface Formulation of…

General Relativity and Quantum Cosmology · Physics 2012-06-08 Emanuel Gallo

We show that a general class of singular K\"ahler metrics with Ricci curvature bounded below define K\"ahler currents. In particular the result applies to singular K\"ahler-Einstein metrics on klt pairs, and an analogous result holds for…

Differential Geometry · Mathematics 2025-02-17 Yifan Chen , Shih-Kai Chiu , Max Hallgren , Gábor Székelyhidi , Tat Dat Tô , Freid Tong

We describe all random sets that satisfy the radial conformal restriction property, therefore providing the analogue in the radial case of results of Lawler, Schramm and Werner in the chordal case.

Probability · Mathematics 2018-05-31 Hao Wu

Compact pseudo-Riemannian manifolds that have parallel Weyl tensor without being conformally flat or locally symmetric are known to exist in infinitely many dimensions greater than 4. We prove some general topological properties of such…

Differential Geometry · Mathematics 2011-06-07 Andrzej Derdzinski , Witold Roter

We investigate the physical spectrum of vector-like SU(N) gauge theories with infrared coupling close to but above the critical value for a conformal phase transition. We use dispersion relations, the momentum dependence of the dynamical…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Appelquist , F. Sannino

We determine conformal symmetry classes for the pp-wave spacetimes. This refines the isometry classification scheme given by Sippel and Goenner (1986 {\it Gen. Rel. Grav.} {\bf 18} 1229). It is shown that every conformal Killing vector for…

General Relativity and Quantum Cosmology · Physics 2013-08-09 Aidan J Keane , Brian O J Tupper

We give a classification of non-Abelian T-duals of the flat metric in D=4 dimensions with respect to the four-dimensional continuous subgroups of the Poincare group. After dualizing the flat background, we identify majority of dual models…

High Energy Physics - Theory · Physics 2017-10-31 Ladislav Hlavaty , Ivo Petr

The visualization of an exceptional point in a PT symmetric directional coupler(DC) is demonstrated. In such a system the exceptional point can be probed by varying only a single parameter. Using the Rayleigh-Schroedinger perturbation…

Quantum Physics · Physics 2008-11-26 Shachar Klaiman , Nimrod Moiseyev , Uwe Gunther

Starting from a 6-dimensional nilpotent Lie group N endowed with an invariant SU(3) structure, we construct a homogeneous conformally parallel G_2-metric on an associated solvmanifold. We classify all half-flat SU(3) structures that endow…

Differential Geometry · Mathematics 2012-06-19 Simon G. Chiossi , Anna Fino

The explicit form of conformal generators is found which provides the extension of Poincare symmetry for massless particles of arbitrary helicity. The helicity 1/2 particles are considered as the particular example. The realization of…

High Energy Physics - Theory · Physics 2020-01-08 Joanna Gonera , Piotr Kosinski , Pawel Maslanka

The main objective of the present paper is to investigate the curvature properties of generalized pp-wave metric. It is shown that generalized pp-wave spacetime is Ricci generalized pseudosymmetric, 2-quasi-Einstein and generalized…

Differential Geometry · Mathematics 2017-02-27 Absos Ali Shaikh , Tran Quoc Binh , Haradhan Kundu

A geometry with parallel skew-symmetric torsion is a Riemannian manifold carrying a metric connection with parallel skew-symmetric torsion. Besides the trivial case of the Levi-Civita connection, geometries with non-vanishing parallel…

Differential Geometry · Mathematics 2021-06-15 Richard Cleyton , Andrei Moroianu , Uwe Semmelmann