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Standard practice attempts to remove coordinate influence in physics through the use of invariant equations. Trans-coordinate physics proceeds differently by not introducing space-time coordinates in the first place. Differentials taken…

Quantum Physics · Physics 2015-03-13 Richard A. Mould

In the present work the problem of distinguishing between essential and spurious (i.e., absorbable) constants contained in a metric tensor field in a Riemannian geometry is considered. The contribution of the study is the presentation of a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. O. Papadopoulos

The scalar invariant, I, constructed from the "square" of the first covariant derivative of the curvature tensor is used to probe the local geometry of static spacetimes which are also Einstein spaces. We obtain an explicit form of this…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Manash Mukherjee , F. P. Esposito , L. C. R. Wijewardhana

We find a one-parameter family of Lagrangian descriptions for classical general relativity in terms of tetrads which are not c-numbers. Rather, they obey exotic commutation relations. These noncommutative properties drop out in the metric…

General Relativity and Quantum Cosmology · Physics 2009-10-31 G. Bimonte , R. Musto , A. Stern , P. Vitale

We analytically derive the covariant form of the Riemann (curvature) tensor for homogeneous Metric-Affine Cosmologies. That is, we present, in a Cosmological setting, the most general covariant form of the full Riemann tensor including also…

General Relativity and Quantum Cosmology · Physics 2021-10-27 Damianos Iosifidis

Riemannian geometry provides the fundamental framework for optimization on nonlinear spaces such as matrix manifolds, which arise in machine learning, signal processing, and robotics. While the underlying theory is classical, existing…

Differential Geometry · Mathematics 2026-05-05 Benyamin Ghojogh

Sparsity-based representations have recently led to notable results in various visual recognition tasks. In a separate line of research, Riemannian manifolds have been shown useful for dealing with features and models that do not lie in…

Machine Learning · Computer Science 2015-05-21 Mehrtash Harandi , Richard Hartley , Chunhua Shen , Brian Lovell , Conrad Sanderson

A covariant functor from the category of generic complex algebraic curves to a category of the AF-algebras is constructed. The construction is based on a representation of the Teichmueller space of a curve by the measured foliations due to…

Algebraic Geometry · Mathematics 2009-06-19 Igor Nikolaev

This paper builds on the theory of generalised functions begun in [1]. The Colombeau theory of generalised scalar fields on manifolds is extended to a nonlinear theory of generalised tensor fields which is diffeomorphism invariant and has…

Functional Analysis · Mathematics 2021-03-17 Eduard A. Nigsch , James A. Vickers

Non-Euclidean constraints are inherent in many kinds of data in computer vision and machine learning, typically as a result of specific invariance requirements that need to be respected during high-level inference. Often, these geometric…

Computer Vision and Pattern Recognition · Computer Science 2017-09-26 Suhas Lohit , Pavan Turaga

Using Gauss's square-roots of the metric components, the diagonal Riemann tensor components for diagonal metrics are calculated. The result is a form which makes their source in the metric directly intuitive and displays an intriguing…

General Mathematics · Mathematics 2019-02-06 Avi Rabinowitz

It is shown that the differential geometry of space-time, can be expressed in terms of the algebra of operators on a bundle of Hilbert spaces. The price for this is that the algebra of smooth functions on space-time has to be made…

Mathematical Physics · Physics 2013-01-08 Michał Eckstein , Michael Heller , Leszek Pysiak , Wiesław Sasin

Differential geomtrical methods for deriving the Dirac equation in Curved Spacetime are presented. Einstein's field equation is applied in a novel manner; in the most current standard reference, Birrell and Davies, 1994 [1], the suggestions…

Mathematical Physics · Physics 2007-05-23 Joseph Saaty

There are many functions which are continuous everywhere but not differentiable at some points, like in physical systems of ECG, EEG plots, and cracks pattern and for several other phenomena. Using classical calculus those functions cannot…

Classical Analysis and ODEs · Mathematics 2015-05-26 Uttam Ghosh , Srijan Sengupta , Susmita Sarkar , Shantanu Das

A geometric representation is found for the previously obtained path integral reduction Jacobian in Wiener-type path integral when quantizing a model mechanical system, which is used to describe the motion of two interacting scalar…

Mathematical Physics · Physics 2023-10-26 S. N. Storchak

We present a Riemannian framework for linear and quadratic discriminant classification on the tangent plane of the shape space of curves. The shape space is infinite dimensional and is constructed out of square root velocity functions of…

In the context of mathematical cosmology, the study of necessary and sufficient conditions for a semi-Riemannian manifold to be a (generalised) Robertson-Walker space-time is important. In particular, it is a requirement for the development…

Differential Geometry · Mathematics 2022-05-30 Kostas Tzanavaris , Pau Amaro Seoane

We seek for an alternative to the metric tensor $g_{\mu\nu}$ as a fundamental geometrical object in four-dimensional Riemannian manifolds. We suggest that the metric tensor $g_{\mu\nu}(P)$ at a given point $P$ of a manifold may be replaced…

General Relativity and Quantum Cosmology · Physics 2010-11-10 Jarmo Mäkelä

We propose a covariant definition of an inertia tensor on spatial hypersurfaces in general relativity, constructed via integrals of geodesic distance functions using the exponential map. In the ADM 3+1 decomposition, we consider a spacelike…

General Relativity and Quantum Cosmology · Physics 2026-01-30 Ilias Kynigalakis

In this paper, we propose a generalization of the Riemann curvature tensor on manifolds (of dimension two or higher) endowed with a Regge metric. Specifically, while all components of the metric tensor are assumed to be smooth within…

Numerical Analysis · Mathematics 2026-01-12 Jay Gopalakrishnan , Michael Neunteufel , Joachim Schöberl , Max Wardetzky