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We investigate the use of dust-scattering rings from GRB 221009A to measure cosmic curvature. We derive the relationship between scattering angle and time delay in non-flat universes and attempt to constrain cosmological parameters by…

High Energy Astrophysical Phenomena · Physics 2024-10-24 Jun-Yi Shen , Yuan-Chuan Zou

The traditional study of plane and space algebraic curves by looking at their tangent vectors, curvatures and torsions provides geometric, but unfortunately not sufficient information about individual curves in order to be able to…

Algebraic Geometry · Mathematics 2021-03-04 Hana Melanova

The aim of these notes is to present an accessible overview of some topics in classical algebraic geometry which have applications to aspects of discrete integrable systems. Precisely, we focus on surface theory on the algebraic geometry…

Algebraic Geometry · Mathematics 2025-10-15 Gessica Alecci , Michele Graffeo , Alexander Stokes

The geometric kernel (or simply the kernel) of a polyhedron is the set of points from which the whole polyhedron is visible. Whilst the computation of the kernel for a polygon has been largely addressed in the literature, fewer methods have…

Computational Geometry · Computer Science 2022-02-15 Tommaso Sorgente , Silvia Biasotti , Michela Spagnuolo

We perform a cosmographic analysis using several cosmological observables such as the luminosity distance moduli, the volume distance, the angular diameter distance and the Hubble parameter. These quantities are determined using different…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jun-Qing Xia , Vincenzo Vitagliano , Stefano Liberati , Matteo Viel

In this paper we review a proposed geometrical formulation of quantum mechanics. We argue that this geometrization makes available mathematical methods from classical mechanics to the quantum frame work. We apply this formulation to the…

Mathematical Physics · Physics 2014-11-21 G. Marmo , G. F. Volkert

The real number system is geometrically extended to include three new anticommuting square roots of plus one, each such root representing the direction of a unit vector along the orthonormal coordinate axes of Euclidean 3-space. The…

General Physics · Physics 2015-09-09 Garret Sobczyk

We study quantum statistical inference tasks of hypothesis testing and their canonical variations, in order to review relations between their corresponding figures of merit---measures of statistical distance---and demonstrate the crucial…

Quantum Physics · Physics 2020-09-25 Marcin Jarzyna , Jan Kolodynski

The standard method for observationally confirming the existence of a predicted finite topology of the universe involves searching for the repetition of the same finite or extended source in different directions. However, serious problems…

Astrophysics · Physics 2007-05-23 Reuven Opher

This is a study of a problem in geodesy with methods from complex algebraic geometry: for a fixed number of measure points and target points at unknown position in the Euclidean plane, we study the problem of determining their relative…

Algebraic Geometry · Mathematics 2015-01-28 Josef Schicho , Matteo Gallet

This paper presents the classification of a general quadric into an axisymmetric quadric (AQ) and the solution to the problem of the proximity of a given point to an AQ. The problem of proximity in $R^3$ is reduced to the same in $R^2$,…

Robotics · Computer Science 2025-10-13 Bibekananda Patra , Aditya Mahesh Kolte , Sandipan Bandyopadhyay

This paper describes an algorithm for determining radii of convergence of power expansions for algebraic functions and the testing done to check it. Since the current methods for computing these series are iterative, standard methods for…

Algebraic Geometry · Mathematics 2013-05-07 Dominic C. Milioto

We present the CosmoBolognaLib, a large set of Open Source C++ numerical libraries for cosmological calculations. CosmoBolognaLib is a living project aimed at defining a common numerical environment for cosmological investigations of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 Federico Marulli , Alfonso Veropalumbo , Michele Moresco

The development of computational techniques in the last decade has made possible to attack some classical problems of algebraic geometry. In this survey, we briefly describe some open problems related to algebraic curves which can be…

Commutative Algebra · Mathematics 2007-05-23 Tanush Shaska

Spherometer is an instrument widely used for measuring the radius of curvature of a spherical surface. Cylindrometer is a modified spherometer, which can measure the radii of both spherical and cylindrical surfaces. Both of these…

General Physics · Physics 2013-11-15 Sameen Ahmed Khan

We investigate the possibility that the quantum theory of gravity could be constructed discretely using algebraic methods. The algebraic tools are similar to ones used in constructing topological quantum field theories.The algebraic tools…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Louis Crane

The horologia are ancient ephemerides, tables of durations of the days and nights during all months of the year. The algorithms used to compute the horologia are here presented and the results are compared with the tables computed by…

History and Philosophy of Physics · Physics 2012-11-13 Costantino Sigismondi

Orbit determination (OD) from three position vectors is one of the classical problems in astrodynamics. Early contributions to this problem were made by J. Willard Gibbs in the late 1800s and OD of this type is known today as ``Gibbs…

Algebraic Geometry · Mathematics 2024-03-15 Michela Mancini , John A. Christian

The purpose of this paper is to explore the question "to what extent could we produce formal, machine-verifiable, proofs in real algebraic geometry?" The question has been asked before but as yet the leading algorithms for answering such…

Symbolic Computation · Computer Science 2021-06-17 Erika {Á}brahám , James Davenport , Matthew England , Gereon Kremer , Zak Tonks

A great deal of experimental effort is currently being devoted to the precise measurements of the cosmic microwave background (CMB) sky in temperature and polarisation. Satellites, balloon-borne, and ground-based experiments scrutinize the…