English
Related papers

Related papers: Two-dimensional metrics admitting precisely one pr…

200 papers

This article provides a new perspective on the geometry of a projective line, which helps clarify and illuminate some classical results about projective plane. As part of the same train of ideas, the article also provides a proof of the…

General Mathematics · Mathematics 2022-05-11 Nicholas Phat Nguyen

A "2-group" is a category equipped with a multiplication satisfying laws like those of a group. Just as groups have representations on vector spaces, 2-groups have representations on "2-vector spaces", which are categories analogous to…

Quantum Algebra · Mathematics 2013-05-17 John C. Baez , Aristide Baratin , Laurent Freidel , Derek K. Wise

A finite subset $X$ of the Euclidean space is called an $m$-distance set if the number of distances between two distinct points in $X$ is equal to $m$. An $m$-distance set $X$ is said to be maximal if any vector cannot be added to $X$ while…

Combinatorics · Mathematics 2020-07-28 Hiroshi Nozaki , Masashi Shinohara

Consider a measurable space with an atomless finite vector measure. This measure defines a mapping of the $\sigma$-field into an Euclidean space. According to the Lyapunov convexity theorem, the range of this mapping is a convex compactum.…

Probability · Mathematics 2011-02-14 Peng Dai , Eugene A. Feinberg

This paper combines two classical theories, namely metric projective differential geometry and superintegrability. We study superintegrable systems on 2-dimensional geometries that share the same geodesics, viewed as unparametrized curves.…

Differential Geometry · Mathematics 2020-02-13 Andreas Vollmer

Two K\"ahler metrics on a complex manifold are called c-projectively equivalent if their $J$-planar curves coincide. These curves are defined by the property that the acceleration is complex proportional to the velocity. We give an explicit…

Differential Geometry · Mathematics 2015-10-02 Alexey V. Bolsinov , Vladimir S. Matveev , Stefan Rosemann

We give a complete solution of a problem in submanifold theory posed and partially solved by the eminent algebraic geometer Pierre Samuel in 1947. Namely, to determine all pairs of immersions of a given manifold into Euclidean space that…

Differential Geometry · Mathematics 2010-04-02 Marcos Dajczer , Ruy Tojeiro

A strictly convex real projective orbifold is equipped with a natural Finsler metric called the Hilbert metric. In the case that the projective structure is hyperbolic, the Hilbert metric and the hyperbolic metric coincide. We prove that…

Geometric Topology · Mathematics 2009-12-31 Daryl Cooper , Kelly Delp

We show that every 2nd order ODE defines a 4-parameter family of projective connections on its 2-dimensional solution space. In a special case of ODEs, for which a certain point transformation invariant vanishes, we find that this family of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ezra T Newman , Pawel Nurowski

In 1992, P. Pol\'{a}\v{c}ik\cite{P2} showed that one could linearly imbed any vector fields into a scalar semi-linear parabolic equation on $\Omega$ with Neumann boundary condition provided that there exists a smooth vector field…

Analysis of PDEs · Mathematics 2007-05-23 Fengbo Hang , Huiqiang Jiang

We present two new constructions in the usual euclidean plane. We only deal with 'Grecian Geometry', with this phrase we mean elementary geometry in the two-dimensional space R 2 . We describe and prove two propositions about 'projections'.…

Metric Geometry · Mathematics 2011-09-13 Volker Thürey

Brief proofs of classical results of Lie on finite dimensional subalgebras of vector fields in two and three variables are outlined. The results for algebras of maximal rank for vector fields in $\mathbb{C}^N$ -- $N$ arbitrary -- are also…

Representation Theory · Mathematics 2026-05-26 Hassan Azad , Indranil Biswas , Said Waqas Shah

let f be an endomorphism of a complex projective space, of degree bigger than one. Let us call an algebraic subset exceptional for f, if its inverse image is set-theoretically equal to itself. J.-Y. Briend, S. Cantat and M. Shishikura…

Algebraic Geometry · Mathematics 2007-05-23 E. Amerik , F. Campana

The equation determining whether a projective structure admits a connection in its given projective class that has skew-symmetric Ricci tensor is an overdetermined system of semi-linear partial differential equations which we call the…

Differential Geometry · Mathematics 2015-06-15 Matthew Randall

In this paper, we prove an upper bound on the second non-zero Laplacian eigenvalue on $n$-dimensional real projective space. The sharp result for 2-dimensions was shown by Nadirashvili and Penskoi and later by Karpukhin when the metric…

Spectral Theory · Mathematics 2024-01-26 Hanna N. Kim

It is understood now that all projective (and conformal) invariants of Riemannian metrics can be found by a transparent construction based on representation theory. So this article with a partial and quite cumbersome construction of…

Differential Geometry · Mathematics 2008-06-17 P. I. Katsylo

We give some remarks on geodesics in the space of K\"ahler metrics that are defined for all time. Such curves are conjecturally induced by holomorphic vector fields, and we show that this is indeed so for regular geodesics, whereas the…

Differential Geometry · Mathematics 2022-05-04 Bo Berndtsson

This is an introduction to geometric algebra, an alternative to traditional vector algebra that expands on it in two ways: 1. In addition to scalars and vectors, it defines new objects representing subspaces of any dimension. 2. It defines…

Mathematical Physics · Physics 2012-05-29 Eric Chisolm

We give a unifying description of all inequivalent vector bundles over the 2-dimensional sphere $S^2$ by constructing suitable global projectors $p$ via equivariant maps. Each projector determines the projective module of finite type of…

Mathematical Physics · Physics 2015-06-26 Giovanni Landi

There are two problems Analytical Geometry with facing anyone who studies this discipline: define the nature of the locus represented by the general equation 2do degree in two or three variables: That curve represents the plane? What…

History and Overview · Mathematics 2013-03-22 Jaime Chica , Jonathan Taborda