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Related papers: Crofton formulas in pseudo-Riemannian space forms

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The classical Crofton formula explains how intrinsic volumes of a convex body $K$ in $n$-dimensional Euclidean space can be obtained from integrating a measurement function at sections of $K$ with invariantly moved affine flats. Motivated…

Metric Geometry · Mathematics 2023-10-03 Emil Dare , Markus Kiderlen

It is shown how new integral-geometric formulae can be obtained from the existing formulae of Crofton type. In particular, for classical Crofton formulae in which the answer depends on the Riemannian volume, we obtain generalizations in…

Differential Geometry · Mathematics 2022-09-08 Dmitri Akhiezer , Boris Kazarnovskii

Generalizing Weyl's tube formula and building on Chern's work, Alesker reinterpreted the Lipschitz-Killing curvature integrals as a family of valuations (finitely-additive measures with good analytic properties), attached canonically to any…

Differential Geometry · Mathematics 2019-12-11 Dmitry Faifman

We study the $O(p,q)$-invariant valuations classified by A. Bernig and the author. Our main result is that every such valuation is given by an $O(p,q)$-invariant Crofton formula. This is achieved by first obtaining a handful of explicit…

Differential Geometry · Mathematics 2017-06-15 Dmitry Faifman , with an appendix joint with Thomas Wannerer

The tensorial curvature measures are tensor-valued generalizations of the curvature measures of convex bodies. We prove a set of Crofton formulae for such tensorial curvature measures. These formulae express the integral mean of the…

Metric Geometry · Mathematics 2016-07-15 Daniel Hug , Jan A. Weis

One constructs new operations of pull-back and push-forward on valuations on manifolds with respect to submersions and immersions. A general Radon type transform on valuations is introduced using these operations and the product on…

Metric Geometry · Mathematics 2014-08-14 Semyon Alesker

We compute the measure with multiplicity of the set of complex planes intersecting a compact domain in a complex space form. The result is given in terms of the so-called hermitian intrinsic volumes. Moreover, we obtain two different…

Differential Geometry · Mathematics 2011-07-21 Judit Abardia , Eduardo Gallego , Gil Solanes

We show how Alesker's theory of valuations on manifolds gives rise to an algebraic picture of the integral geometry of any Riemannian isotropic space. We then apply this method to give a thorough account of the integral geometry of the…

Differential Geometry · Mathematics 2015-09-24 Andreas Bernig , Joseph H. G. Fu , Gil Solanes

The recently introduced Lipschitz-Killing curvature measures on pseudo-Riemannian manifolds satisfy a Weyl principle, i.e. are invariant under isometric embeddings. We show that they are uniquely characterized by this property. We apply…

Differential Geometry · Mathematics 2022-09-14 Andreas Bernig , Dmitry Faifman , Gil Solanes

We write down Crofton formulas--expressions that compute lengths of spacelike curves in asymptotically AdS$_3$ geometries as integrals over kinematic space--which apply when the curve and/or the background spacetime is time-dependent.…

High Energy Physics - Theory · Physics 2020-12-30 Bartlomiej Czech , Yaithd D. Olivas , Zi-zhi Wang

We study curvature invariants of a sub-Riemannian manifold (i.e., a manifold with a Riemannian metric on a non-holonomic distribution) related to mutual curvature of several pairwise orthogonal subspaces of the distribution, and prove…

Differential Geometry · Mathematics 2022-12-27 Vladimir Rovenski

We construct a class of Finsler metrics in three-dimensional space such that all their geodesics are lines, but not all planes are extremal for their Hausdorff area functionals. This shows that if the Hausdorff measure is used as notion of…

Differential Geometry · Mathematics 2011-09-21 Juan Carlos Alvarez Paiva , Gautier Berck

This paper proposes an original Riemmanian geometry for low-rank structured elliptical models, i.e., when samples are elliptically distributed with a covariance matrix that has a low-rank plus identity structure. The considered geometry is…

Differential Geometry · Mathematics 2020-01-07 Florent Bouchard , Arnaud Breloy , Guillaume Ginolhac , Alexandre Renaux , Frédéric Pascal

We consider the Whitney problem for valuations: does a smooth $j$-homogeneous translation-invariant valuation on $\mathbb R^n$ exist that has given restrictions to a fixed family $S$ of linear subspaces? A necessary condition is…

Differential Geometry · Mathematics 2025-02-12 Dmitry Faifman , Georg C. Hofstätter

We obtain a Principal Kinematic Formula and a Crofton Formula for surface area measures of convex bodies, both involving linear operators on the vector space of signed measures on the unit sphere $S^{d-1}$. These formulas are related to a…

Metric Geometry · Mathematics 2015-07-14 Paul Goodey , Daniel Hug , Wolfgang Weil

We survey recent results in hermitian integral geometry, i.e. integral geometry on complex vector spaces and complex space forms. We study valuations and curvature measures on complex space forms and describe how the global and local…

Differential Geometry · Mathematics 2019-04-02 Andreas Bernig

We show the fundamental theorems of curves and surfaces in the 3-dimensional Heisenberg group and find a complete set of invariants for curves and surfaces respectively. The proofs are based on Cartan's method of moving frames and Lie group…

Differential Geometry · Mathematics 2017-12-27 Hung-Lin Chiu , Yen-Chang Huang , Sin-Hua Lai

We study sequences of conformal deformations of a smooth closed Riemannian manifold of dimension $n$, assuming uniform volume bounds and $L^{n/2}$ bounds on their scalar curvatures. Singularities may appear in the limit. Nevertheless, we…

Differential Geometry · Mathematics 2021-12-22 Clara L. Aldana , Gilles Carron , Samuel Tapie

We establish formulas that give the intrinsic volumes, or curvature measures, of sublevel sets of functions defined on Riemannian manifolds as integrals of functionals of the function and its derivatives. For instance, in the Euclidean…

Differential Geometry · Mathematics 2024-05-21 Benoît Jubin

We study collections of exact Lagrangian submanifolds respecting some uniform Riemannian bounds, which we equip with a metric naturally arising in symplectic topology (e.g. the Lagrangian Hofer metric or the spectral metric). We exhibit…

Symplectic Geometry · Mathematics 2024-07-17 Jean-Philippe Chassé
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