English
Related papers

Related papers: On the microlocal analysis of the geodesic X-ray t…

200 papers

We present a numerical implementation of the geodesic ray transform and its inversion over functions and solenoidal vector fields on two-dimensional Riemannian manifolds. For each problem, inversion formulas previously derived in…

Differential Geometry · Mathematics 2014-04-17 François Monard

In this article, we study the properties of the geodesic X-ray transform for asymptotically Euclidean or conic Riemannian metrics and show injectivity under non-trapping and no conjugate point assumptions. We also define a notion of lens…

Differential Geometry · Mathematics 2021-02-09 Colin Guillarmou , Matti Lassas , Leo Tzou

We show that on a two-dimensional compact nontrapping Riemannian manifold with strictly convex boundary, a piecewise constant function can be recovered from its integrals over geodesics. We adapt the injectivity proof which uses variations…

Differential Geometry · Mathematics 2020-01-20 Vadim Lebovici

We initiate a study of the inversion of the geodesic X-ray transform $I_m$ over symmetric $m$-tensor fields on asymptotically hyperbolic surfaces. This operator has a non-trivial kernel whenever $m\ge 1$. To propose a gauge representative…

Differential Geometry · Mathematics 2025-10-07 Nikolas Eptaminitakis , François Monard , Yuzhou Joey Zou

Let $X$ be a compact Riemannian manifold with conic singularities, i.e. a Riemannian manifold whose metric has a conic degeneracy at the boundary. Let $\Delta$ be the Friedrichs extension of the Laplace-Beltrami operator on $X.$ There are…

Analysis of PDEs · Mathematics 2007-05-23 Jared Wunsch

We initiate the study of X-ray tomography on sub-Riemannian manifolds, for which the Heisenberg group exhibits the simplest nontrivial example. With the language of the group Fourier Transform, we prove an operator-valued incarnation of the…

Differential Geometry · Mathematics 2020-10-22 Steven Flynn

We study the problem of proper discretizing and sampling issues related to geodesic X-ray transforms on simple surfaces, and illustrate the theory on simple geodesic disks of constant curvature. Given a notion of band limit on a function,…

Analysis of PDEs · Mathematics 2022-12-07 François Monard , Plamen Stefanov

We consider the normal operator of the X-ray transform, weighted with Gaussian weights, in Euclidean space with dimension at least 3. We show the eigenfunctions of the normal operator are joint eigenfunctions of the harmonic oscillator and…

Analysis of PDEs · Mathematics 2026-05-05 Yuzhou Joey Zou

Consider a compact Riemannian manifold of dimension $\geq 3$ with strictly convex boundary, such that the manifold admits a strictly convex function. We show that the attenuated ray transform in the presence of an arbitrary connection and…

Differential Geometry · Mathematics 2018-06-05 Gabriel P. Paternain , Mikko Salo , Gunther Uhlmann , Hanming Zhou

We show that on a two-dimensional compact nontrapping manifold with strictly convex boundary, a piecewise constant function is determined by its integrals over geodesics. In higher dimensions, we obtain a similar result if the manifold…

Differential Geometry · Mathematics 2017-02-27 Joonas Ilmavirta , Jere Lehtonen , Mikko Salo

We give an explicit Singular Value Decomposition of the sub-Riemannian X-ray transform on the Heisenberg group with compact center. By studying the singular values, we obtain a two-radius theorem for integrals over sub-Riemannian geodesics.…

Analysis of PDEs · Mathematics 2023-05-09 Steven Flynn

The X-ray transform on the plane or on the three-dimensional Euclidean space can be considered as the measurements of CT scanners for normal human tissue. If the human body contains metal regions such as dental implants, stents in blood…

Analysis of PDEs · Mathematics 2026-02-25 Hiroyuki Chihara

In this paper, we consider the inverse problem of determining an unknown function defined in three space dimensions from its geodesic X-ray transform. The standard X-ray transform is defined on the Euclidean metric and is given by the…

Numerical Analysis · Mathematics 2018-04-27 Tak Shing Au Yeung , Eric T. Chung , Gunther Uhlmann

We prove injectivity and a support theorem for the X-ray transform on $2$-step nilpotent Lie groups with many totally geodesic $2$-dimensional flats. The result follows from a general reduction principle for manifolds with uniformly…

Differential Geometry · Mathematics 2016-01-19 Norbert Peyerimhoff , Evangelia Samiou

We consider the standard hypergeometric differential operator $D$ regarded as an operator on the complex plane $C$ and the complex conjugate operator $\overline D$. These operators formally commute and are formally adjoint one to another…

Functional Analysis · Mathematics 2021-05-25 Vladimir F. Molchanov , Yury A. Neretin

We study a one-parameter family of self-adjoint normal operators for the X-ray transform on the closed Euclidean disk ${\mathbb D}$, obtained by considering specific singularly weighted $L^2$ topologies. We first recover the well-known…

Analysis of PDEs · Mathematics 2022-12-07 Rohit Kumar Mishra , François Monard , Yuzhou Zou

We construct an explicit inversion formula for Guillarmou's normal operator on closed surfaces of constant negative curvature. This normal operator can be defined as a weak limit for an "attenuated normal operator", and we prove this…

Differential Geometry · Mathematics 2025-01-14 Sean Richardson

We give reconstruction formulas inverting the geodesic X-ray transform over functions (call it $I_0$) and solenoidal vector fields on surfaces with negative curvature and strictly convex boundary. These formulas generalize the…

Differential Geometry · Mathematics 2015-11-18 Colin Guillarmou , François Monard

In this paper we consider the geodesic X-ray transform with attenuation coefficient as a combination of smooth complex function and 1-form. We show that attenuated X-ray transform applied to the pair of tensors is injective modulo the…

Differential Geometry · Mathematics 2017-03-07 Yernat M. Assylbekov

Let $G$ denote a connected semisimple and simply connected algebraic group over an algebraically closed field $k$ of positive characteristic and let $g$ denote a regular element of $G$. Let $X$ denote any equivariant embedding of $G$. We…

Algebraic Geometry · Mathematics 2007-05-23 Jesper Funch Thomsen