English
Related papers

Related papers: 3 methods to put a Riemannian metric on Shape Spac…

200 papers

We develop a geometric framework in Feynman-parameter space to determine constraints on the sequential discontinuities of Feynman integrals. Our method is based on tracking the deformation of the integration contour as external kinematics…

High Energy Physics - Theory · Physics 2026-02-24 Ruth Britto , Holmfridur S. Hannesdottir

Traditional machine learning (ML) algorithms, such as multiple regression, require human analysts to make decisions on how to treat the data. These decisions can make the model building process subjective and difficult to replicate for…

Machine Learning · Computer Science 2022-01-31 William Franz Lamberti

Many applications in 3D shape design and augmentation require the ability to make specific edits to an object's semantic parameters (e.g., the pose of a person's arm or the length of an airplane's wing) while preserving as much existing…

Computer Vision and Pattern Recognition · Computer Science 2020-11-11 Fangyin Wei , Elena Sizikova , Avneesh Sud , Szymon Rusinkiewicz , Thomas Funkhouser

A new method of metric space investigation, based on classification of its finite subspaces, is suggested. It admits to derive information on metric space properties which is encoded in metric. The method describes geometry in terms of only…

Metric Geometry · Mathematics 2007-05-23 Yuri A. Rylov

It is well known that one can parameterize 2-D Riemannian structures by conformal transformations and diffeomorphisms of fiducial constant curvature geometries; and that this construction has a natural setting in general relativity theory…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. Gegenberg , G. Kunstatter

Many procedures in science, engineering and medicine produce data in the form of geometric shapes. Mathematically, a shape can be modeled as an un-parameterized immersed sub-manifold, which is the notion of shape used here. Endowing shape…

Differential Geometry · Mathematics 2012-11-16 Philipp Harms

A semi-Riemannian metric in a n-manifold has n(n-1)/2 degrees of freedom, i.e. as many as the number of components of a differential 2-form. We prove that any semi-Riemannian metric can be obtained as a deformation of a constant curvature…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Josep Llosa , Daniel Soler

In this paper, we describe a novel shape classification method which is embedded in the Bayesian paradigm. We discuss the modelling and the resulting shape classification algorithm for two and three dimensional data shapes. We conclude by…

Methodology · Statistics 2018-03-01 Thomai Tsiftsi

A main goal in the field of statistical shape analysis is to define computable and informative metrics on spaces of immersed manifolds, such as the space of curves in a Euclidean space. The approach taken in the elastic shape analysis…

Differential Geometry · Mathematics 2022-09-21 Martin Bauer , Nicolas Charon , Eric Klassen , Sebastian Kurtek , Tom Needham , Thomas Pierron

In shape optimisation it is desirable to obtain deformations of a given mesh without negative impact on the mesh quality. We propose a new algorithm using least square formulations of the Cauchy-Riemann equations. Our method allows to…

Optimization and Control · Mathematics 2021-06-09 José A. Iglesias , Kevin Sturm , Florian Wechsung

The knowledge of receiver beam shapes is essential for accurate radio interferometric imaging. Traditionally, this information is obtained by holographic techniques or by numerical simulation. However, such methods are not feasible for an…

Instrumentation and Methods for Astrophysics · Physics 2013-07-19 Sarod Yatawatta

Shape optimization is commonly applied in engineering to optimize shapes with respect to an objective functional relying on PDE solutions. In this paper, we view shape optimization as optimization on Riemannian shape manifolds. We consider…

Optimization and Control · Mathematics 2025-04-09 Estefania Loayza-Romero , Kathrin Welker

We consider a $3$-dimensional differentiable manifold with two circulant structures -- a Riemannian metric and an additional structure, whose third power is the identity. The structure is compatible with the metric such that an isometry is…

Differential Geometry · Mathematics 2017-03-31 Georgi Dzhelepov

We give a method for modeling solid objects undergoing large spatially varying and/or anisotropic strains, and use it to reconstruct human anatomy from medical images. Our novel shape deformation method uses plastic strains and the Finite…

Graphics · Computer Science 2020-08-04 Bohan Wang , George Matcuk , Jernej Barbic

Local and global illumination were recently defined in Riemannian manifolds to visualize classical Non-Euclidean spaces. This work focuses on Riemannian metric construction in $\mathbb{R}^3$ to explore special effects like warping, mirages,…

Graphics · Computer Science 2020-05-13 Tiago Novello , Vinícius da Silva , Luiz Velho

Estimating the body shape and posture of a dressed human subject in motion represented as a sequence of (possibly incomplete) 3D meshes is important for virtual change rooms and security. To solve this problem, statistical shape spaces…

Computer Vision and Pattern Recognition · Computer Science 2015-03-30 Stefanie Wuhrer , Leonid Pishchulin , Alan Brunton , Chang Shu , Jochen Lang

We propose a measure of shape which is appropriate for the study of a complicated geometric structure, defined using the topology of neighborhoods of the structure. One aspect of this measure gives a new notion of fractal dimension. We…

Algebraic Topology · Mathematics 2010-12-20 Robert MacPherson , Benjamin Schweinhart

A novel perturbative method, proposed by Panda {\it et al.} [1] to solve the Helmholtz equation in two dimensions, is extended to three dimensions for general boundary surfaces. Although a few numerical works are available in the literature…

Mathematical Physics · Physics 2016-06-21 Subhasis Panda , S. Pratik Khastgir

This paper proposes a generalized framework with joint normalization which learns lower-dimensional subspaces with maximum discriminative power by making use of the Riemannian geometry. In particular, we model the similarity/dissimilarity…

Computer Vision and Pattern Recognition · Computer Science 2017-11-20 Tianci Liu , Zelin Shi , Yunpeng Liu

Consider the sum of the first $N$ eigenspaces for the Laplacian on a Riemannian manifold. A basis for this space determines a map to Euclidean space and for $N$ sufficiently large the map is an embedding. In analogy with a fruitful idea of…

Differential Geometry · Mathematics 2014-04-30 Eric Potash