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相关论文: Microlocal analysis of the X-ray transform in non-…

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Consider a Riemannian manifold in dimension $n\geq 3$ with strictly convex boundary. We prove the local invertibility, up to potential fields, of the geodesic ray transform on tensor fields of rank four near a boundary point. This problem…

微分几何 · 数学 2020-01-08 Maarten V. de Hoop , Gunther Uhlmann , Jian Zhai

In this article, we study the microlocal properties of the geodesic ray transform of symmetric $m$-tensor fields on 2-dimensional Riemannian manifolds with boundary allowing the possibility of conjugate points. As is known from an earlier…

微分几何 · 数学 2025-01-09 Sean Holman , Venkateswaran P. Krishnan

The geodesic orbit property is useful and interesting in Riemannian geometry. It implies homogeneity and has important classes of Riemannian manifolds as special cases. Those classes include weakly symmetric Riemannian manifolds and…

微分几何 · 数学 2022-08-25 Yuri Nikolayevsky , Joseph A. Wolf

The Euclidean scattering transform was introduced nearly a decade ago to improve the mathematical understanding of convolutional neural networks. Inspired by recent interest in geometric deep learning, which aims to generalize convolutional…

机器学习 · 统计学 2023-07-26 Michael Perlmutter , Feng Gao , Guy Wolf , Matthew Hirn

Let $\mathcal{M}$ be a compact, smooth, $n$-dimensional Riemannian manifold without boundary. In this paper, we generalize nonwindowed geometric scattering transforms, which we formulate as $\mathbf{L}^q(\mathcal{M})$ norms of a cascade of…

泛函分析 · 数学 2024-02-19 Albert Chua , Yang Yang

On simple geodesic disks of constant curvature, we derive new functional relations for the geodesic X-ray transform, involving a certain class of elliptic differential operators whose ellipticity degenerates normally at the boundary. We…

偏微分方程分析 · 数学 2020-07-20 François Monard

Let $g$ be a Riemannian metric for $\mathbf{R}^d$ ($d\geq 3$) which differs from the Euclidean metric only in a smooth and strictly convex bounded domain $M$. The lens rigidity problem is concerned with recovering the metric $g$ inside $M$…

微分几何 · 数学 2017-02-28 Gang Bao , Hai Zhang

Let (M,g) be an analytic, compact, Riemannian manifold with boundary, of dimension n >= 2. We study a class of generalized Radon transforms, integrating over a family of hypersurfaces embedded in M, satisfying the Bolker condition [23].…

微分几何 · 数学 2015-05-06 Andrew Homan , Hanming Zhou

We consider the nonlinear problem of determining a connection and a Higgs field from the corresponding parallel transport along geodesics on a Riemannian manifold with boundary, in any dimension. The problem can be reduced to an integral…

偏微分方程分析 · 数学 2016-10-18 Hanming Zhou

Any smooth geodesic flow is locally integrable with smooth integrals. We show that generically this fails if we require, in addition, that the integrals are polynomial (or, more generally, analytic) in momenta. Consequently we obtain that a…

微分几何 · 数学 2018-02-05 Boris Kruglikov , Vladimir S. Matveev

In this work we study the general system of geodesic equations for the case of a massive particle moving on an arbitrary curved manifold. The investigation is carried out from the symmetry perspective. By exploiting the parametrization…

广义相对论与量子宇宙学 · 物理学 2019-06-05 N. Dimakis , Petros A. Terzis , T. Christodoulakis

We analyze a variational time discretization of geodesic calculus on finite- and certain classes of infinite-dimensional Riemannian manifolds. We investigate the fundamental properties of discrete geodesics, the associated discrete…

数值分析 · 数学 2013-03-25 Martin Rumpf , Benedikt Wirth

In this paper we study the computation of both algebraic and non-algebraic tensor functions under the tensor-tensor multiplication with linear maps. In the case of algebraic tensor functions, we prove that the asymptotic exponent of both…

数值分析 · 数学 2025-10-20 Jeong-Hoon Ju , Susana Lopez-Moreno

We study the problem of recovering a function on a pseudo-Riemannian manifold from its integrals over all null geodesics in three geometries: pseudo-Riemannian products of Riemannian manifolds, Minkowski spaces and tori. We give proofs of…

微分几何 · 数学 2016-08-11 Joonas Ilmavirta

For smooth compact connected manifolds with strictly convex boundary, no conjugate points and a hyperbolic trapped set, we prove an equivalence principle concerning the injectivity of the X-ray transform $I_m$ on symmetric solenoidal…

偏微分方程分析 · 数学 2019-08-08 Thibault Lefeuvre

We prove that the isometric embedding of any metric of differentiability class C1 in E3 exists. We use simplified notation for the given metric, namely geodesic parameters, and level parameters for the embedded surface in E3. Central to our…

微分几何 · 数学 2022-10-07 Edgar Kann

We construct smooth metrics on 2-manifold with nonpositive Gauss curvature which cannot be (C^3) locally isometrically embedded in R^3. Moreover, the Gauss curvature of the metric can be made negative except for one point.

微分几何 · 数学 2007-05-23 Nikolai Nadirashvili , Yu Yuan

The present article proposes a partial answer to the explicit inversion of the tensor tomography problem in two dimensions, by proving injectivity over certain kinds of tensors and providing reconstruction formulas for them. These tensors…

偏微分方程分析 · 数学 2015-06-18 François Monard

Given a smooth polarized Riemann surface (X, L) endowed with a hyperbolic metric $\omega$ with cusp singularities along a divisor D, we show the L^2 projective embedding of (X, D) defined by L^k is asymptotically almost balanced in a…

微分几何 · 数学 2017-09-26 Jingzhou Sun , Song Sun

This note is a continuation of the author's paper \cite{Li}. We prove that if the metric $g$ of a 4-manifold has bounded Ricci curvature and the curvature has no local concentration everywhere, then it can be smoothed to a metric with…

微分几何 · 数学 2009-11-17 Ye Li