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We define a formal Riemannian metric on a given conformal class of metrics on a closed Riemann surface. We show interesting formal properties for this metric, in particular the curvature is nonpositive and the Liouville energy is…

Differential Geometry · Mathematics 2015-07-20 Matthew J. Gursky , Jeffrey Streets

We study two types of isotropic planes: weakly isotropic and strongly isotropic planes. We prove that a Riemannian manifold of indefinite metric is conformally flat if and only if its curvature tensor vanishes on all the strongly isotropic…

Differential Geometry · Mathematics 2010-08-12 Adrijan Borisov , Georgi Ganchev , Ognian Kassabov

It is known that on a closed manifold of dimension greater than one, every smooth weak Riemannian metric on the space of smooth positive densities that is invariant under the action of the diffeomorphism group, is of the form $$…

Differential Geometry · Mathematics 2019-02-06 Martins Bruveris , Peter W. Michor

In this paper, we show that small spherical soap bubbles in irreducible simply connected symmetric spaces of rank greater than one are constructed from the limits of a certain kind of modified mean curvature flows starting from small…

Differential Geometry · Mathematics 2020-04-03 Naoyuki Koike

For a $2$-dimensional non-flat spray we associate a Berwald frame and a $3$-dimensional distribution that we call the Berwald distribution. The Frobenius integrability of the Berwald distribution characterises the Finsler metrizability of…

Differential Geometry · Mathematics 2018-02-15 Ioan Bucataru , Georgeta Creţu , Ebtsam H. Taha

Two positive scalar curvature metrics $g_0$, $g_1$ on a manifold $M$ are psc-isotopic if they are homotopic through metrics of positive scalar curvature. It is well known that if two metrics $g_0$, $g_1$ of positive scalar curvature on a…

Differential Geometry · Mathematics 2013-10-15 Boris Botvinnik

The evolution equation for the shear is reobtained for a spherically symmetric anisotropic, viscous dissipative fluid distribution, which allows us to investigate conditions for the stability of the shear-free condition. The specific case…

General Relativity and Quantum Cosmology · Physics 2015-05-18 L. Herrera , A. Di Prisco , J. Ospino

We start with a recently introduced spherically symmetric geodesic fluid model (arXiv: 1601.07030) whose energy-momentum tensor in the comoving frame is dust-like with nontrivial energy flux. In the non-comoving energy frame (vanishing…

General Physics · Physics 2018-02-14 Peter C. Stichel

A stochastic method is introduced for geometric modeling aerosol surface roughness with random field and discrete differential geometry theory. Optical scattering properties are computed for randomly oriented spheroidal particles with…

Atmospheric and Oceanic Physics · Physics 2017-10-24 Jianing Zhang

See http://www.youtube.com/watch?v=izbGXdjvK_I for a YouTube video showing part of the results in this paper.We will consider surfaces whose mean curvature at a point is a linear function of the square of the distance from that point to the…

Differential Geometry · Mathematics 2014-04-14 Bennett Palmer , Oscar Perdomo

We define spherical diffraction measures for a wide class of weighted point sets in commutative spaces, i.e. proper homogeneous spaces associated with Gelfand pairs. In the case of the hyperbolic plane we can interpret the spherical…

Dynamical Systems · Mathematics 2020-02-14 Michael Björklund , Tobias Hartnick , Felix Pogorzelski

In this paper, we study self-expanding solutions to a large class of parabolic inverse curvature flows by homogeneous symmetric functions of principal curvatures in Euclidean spaces. These flows include the inverse mean curvature flow and…

Differential Geometry · Mathematics 2018-06-19 Tsz-Kiu Aaron Chow , Ka-Wing Chow , Frederick Tsz-Ho Fong

We introduce and study the flow of metrics on a foliated Riemannian manifold $(M,g)$, whose velocity along the orthogonal distribution is proportional to the mixed scalar curvature, $\Sc_{\,\rm mix}$. The flow is used to examine the…

Differential Geometry · Mathematics 2014-02-11 Vladimir Rovenski , Leonid Zelenko

This paper introduces a set of numerical methods for Riemannian shape analysis of 3D surfaces within the setting of invariant (elastic) second-order Sobolev metrics. More specifically, we address the computation of geodesics and geodesic…

Computer Vision and Pattern Recognition · Computer Science 2025-01-07 Emmanuel Hartman , Yashil Sukurdeep , Eric Klassen , Nicolas Charon , Martin Bauer

We identify the smooth metrics $\mc{M}(M)$ on a manifold $M^n$ with the smooth isometric embeddings $f_g: (M,g) \rightarrow (\mb{S}^{\tn}, \tg)$ into a standard sphere of large dimension $\tn=\tn(n)$, and their Palais isotopic deformations,…

Differential Geometry · Mathematics 2025-11-18 Santiago R. Simanca

The full set of equations governing the structure and the evolution of self--gravitating cylindrically symmetric dissipative fluids with anisotropic stresses, is written down in terms of scalar quantities obtained from the orthogonal…

General Relativity and Quantum Cosmology · Physics 2012-09-11 L. Herrera , A. Di Prisco J. Ospino

Various substances in the liquid state tend to form droplets. In this paper the shape of such droplets is investigated within the spherical model of a lattice gas. We show that in this case the droplet boundary is always diffusive, as…

Statistical Mechanics · Physics 2015-05-20 Anatoly E. Patrick

We study homogeneous curves on some classes of reductive homogeneous spaces G=H which are geodesics with respect to any G-invariant metric on G=H. These curves are called equigeodesics. The spaces we consider are certain Stiefel manifolds…

Differential Geometry · Mathematics 2021-06-04 Marina Statha

From a spray space $S$ on a manifold $M$ we construct a new geometric space $P$ of larger dimension with the following properties: 1. Geodesics in $P$ are in one-to-one correspondence with parallel Jacobi fields of $M$. 2. $P$ is complete…

Differential Geometry · Mathematics 2010-09-20 Ioan Bucataru , Matias F. Dahl

We consider real isotropic geodesics on manifolds endowed with a pseudoconformal structure and their applications to the theory of lightlike hypersurfaces on such manifolds, the geometry of four-dimensional conformal structures of…

Differential Geometry · Mathematics 2007-05-23 Maks A. Akivis , Vladislav V. Goldberg