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Related papers: The geodesic X-ray transform with fold caustics

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Let $(M,g)$ be a simple Riemannian manifold. Under the assumption that the metric $g$ is real-analytic, it is shown that if the geodesic ray transform of a function $f\in L^{2}(M)$ vanishes on an appropriate open set of geodesics, then…

Differential Geometry · Mathematics 2008-03-29 V. Krishnan

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 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…

General Relativity and Quantum Cosmology · Physics 2019-06-05 N. Dimakis , Petros A. Terzis , T. Christodoulakis

We show that the existence of a function in $L^{1}$ with constant geodesic X-ray transform imposes geometrical restrictions on the manifold. The boundary of the manifold has to be umbilical and in the case of a strictly convex Euclidean…

Differential Geometry · Mathematics 2019-09-04 Joonas Ilmavirta , Gabriel P. Paternain

We consider a gauge-invariant, mass-independent prescription for renormalizing composite operators, regularized on the lattice, in the spirit of the coordinate space (X-space) renormalization scheme. The prescription involves only Green's…

High Energy Physics - Lattice · Physics 2021-05-19 M. Costa , I. Karpasitis , G. Panagopoulos , H. Panagopoulos , T. Pafitis , A. Skouroupathis , G. Spanoudes

We exhibit the form of the ``radiation field,'' describing the large-scale, long-time behavior of solutions to the wave equation on a manifold with no trapped rays, as a Fourier integral operator. We work in two different geometric…

Analysis of PDEs · Mathematics 2007-05-23 Antonio Sa Barreto , Jared Wunsch

A general classification of linear differential and finite-difference operators possessing a finite-dimensional invariant subspace with a polynomial basis is given. The main result is that any operator with the above property must have a…

High Energy Physics - Theory · Physics 2008-02-03 Alexander Turbiner

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

We consider the third order operator with periodic coefficients on the real line. This operator is used in the integration of the non-linear evolution Boussinesq equation. For the minimal smoothness of the coefficients we prove that: 1) the…

Mathematical Physics · Physics 2011-12-21 A. Badanin , E. Korotyaev

We prove a uniform generalized gaussian bound for the powers of a discrete convolution operator in one space dimension. Our bound is derived under the assumption that the Fourier transform of the coefficients of the convolution operator is…

Numerical Analysis · Mathematics 2021-11-23 Jean-François Coulombel , Grégory Faye

Let a differential 4D-manifold with a smooth coframe field be given. Consider the operators on it that are linear in the second order derivatives or quadratic in the first order derivatives of the coframe, both with coefficients that depend…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Yakov Itin , Shmuel Kaniel

In this paper we consider the solvability of pseudodifferential operators in the case when the principal symbol vanishes of order $k \ge 2 $ at a nonradial involutive manifold $\Sigma_2$. We shall assume that the operator is of subprincipal…

Analysis of PDEs · Mathematics 2018-01-24 Nils Dencker

In this article, we develop a pseudodifferential calculus on a general filtered manifold M . The symbols are fields of operators $\sigma$(x, $\pi$) parametrised by x $\in$ M and the unitary dual G x M of the osculating Lie group G x M . We…

Functional Analysis · Mathematics 2026-04-16 Clotilde Fermanian Kammerer , Véronique Fischer , Steven Flynn

The iteration procedure of supersymmetric transformations for the two-dimensional Schroedinger operator is implemented by means of the matrix form of factorization in terms of matrix 2x2 supercharges. Two different types of iterations are…

High Energy Physics - Theory · Physics 2011-07-28 F. Cannata , M. V. Ioffe , A. I. Neelov , D. N. Nishnianidze

Let V be a simple vertex operator algebra and G a finite automorphism group. Then there is a natural right G-action on the set of all inequivalent irreducible V-modules. Let S be a finite set of inequivalent irreducible V-modules which is…

Quantum Algebra · Mathematics 2007-05-23 C. Dong , G. Yamskulna

Families of conformal field theories are naturally endowed with a Riemannian geometry which is locally encoded by correlation functions of exactly marginal operators. We show that the curvature of such conformal manifolds can be computed…

High Energy Physics - Theory · Physics 2023-08-09 Bruno Balthazar , Clay Cordova

For the light ray transform on globally hyperbolic Lorentzian manifolds of dimension $n+1 \geq 3$ acting on compactly supported distributions, we show that the Schwartz kernel of the normal operator is a paired Lagrangian distribution with…

Analysis of PDEs · Mathematics 2021-04-20 Yiran Wang

Most of the known non-invertible symmetries of quantum field theories in three and four spacetime dimensions act invertibly on local operators. An exception is coset symmetries, which can be constructed from gauging a non-normal subgroup of…

High Energy Physics - Theory · Physics 2026-03-05 Pavel Putrov , Rajath Radhakrishnan

We consider a class of pseudodifferential operators with a doubly characteristic point, where the quadratic part of the symbol fails to be elliptic but obeys an averaging assumption. Under suitable additional assumptions, semiclassical…

Analysis of PDEs · Mathematics 2016-07-14 Joe Viola
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