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The distribution of the cosmic convergence field is modeled using a large-deviation principle where all non-Gaussian contributions are computed from first principles. The geometry of the past light cone is accounted for by constructing the…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-22 Alexandre Barthelemy , Sandrine Codis , Cora Uhlemann , Francis Bernardeau , Raphael Gavazzi

These lectures were addressed to nonspecialists willing to learn some basic facts, approaches, tools and observational evidence which conform modern cosmology. The aim is also to try to complement the many excellent treatises that exists on…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Emilio Elizalde

Recently we solved the Einstein's field equations to obtain the exact solution of the cosmological model with the Morris-Thorne type wormhole. We found the apparent horizons and analyzed their geometric natures, including the causal…

General Relativity and Quantum Cosmology · Physics 2019-06-21 Sung-Won Kim

I review the major concordances and controversies of the meeting concerning observations. Cosmologists are nearing agreement on the global cosmological parameters of the Universe. A few parameters still have large error bars, notably…

Astrophysics · Physics 2009-09-29 S. M. Faber

Naturalness problems such as the hierarchy problem and the origin of dark energy remain significant challenges in modern cosmology. This paper develops a rigorous mathematical framework where each observer defines their own universe, and…

General Relativity and Quantum Cosmology · Physics 2025-05-13 Ruby P. Madeimy

Cosmology has come a long way from being based on a small number of observations to being a data-driven precision science. We discuss the questions "What is observable?", "What in the Universe is knowable?" and "What are the fundamental…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-28 Florent Leclercq , Alice Pisani , Benjamin D. Wandelt

In this thesis, the implications of a new cosmological model are studied, which has features similar to that of decaying vacuum cosmologies. Decaying vacuum (or cosmological constant \Lambda) models are the results of attempts to resolve…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Moncy V. John

We present a novel derivation of both the Minkowski metric and Lorentz transformations from the consistent quantification of a causally ordered set of events with respect to an embedded observer. Unlike past derivations, which have relied…

Mathematical Physics · Physics 2014-12-22 Kevin H. Knuth , Newshaw Bahreyni

Over the last decades, observations with increasing quality have revolutionized our understanding of the general properties of the Universe. Questions posed for millenia by mankind about the origin, evolution and structure of the cosmos…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 Ricardo T. Génova-Santos

We use astrophysical data to shed light on fundamental physics by constraining parametrized theoretical cosmological and gravitational models. Gravitational parameters are those constants that parametrize possible departures from Einstein's…

Astrophysics · Physics 2008-08-18 Yi Mao

In this position paper we suggest a possible metric approach to shape comparison that is based on a mathematical formalization of the concept of observer, seen as a collection of suitable operators acting on a metric space of functions.…

Computational Geometry · Computer Science 2016-03-08 Patrizio Frosini

It is believed that some numerical technique must be employed for the determination of the system parameters of a visual binary or a star with a planet because the relevant equations are not only highly nonlinear but also transcendental…

Astrophysics · Physics 2015-06-24 Hideki Asada , Toshio Akasaka , Masumi Kasai

The objective of this paper is to rectify any monocular image by computing a homography matrix that transforms it to a bird's eye (overhead) view. We make the following contributions: (i) we show that the homography matrix can be…

Computer Vision and Pattern Recognition · Computer Science 2020-09-29 Ammar Abbas , Andrew Zisserman

Finite metric spaces arise in many different contexts. Enormous bodies of data, scientific, commercial and others can often be viewed as large metric spaces. It turns out that the metric of graphs reveals a lot of interesting information.…

Combinatorics · Mathematics 2007-05-23 Nathan Linial

Extending the study of spherically symmetric metrics satisfying the dominant energy condition and exhibiting singularities of power-law type initiated in SI93, we identify two classes of peculiar interest: focusing timelike singularity…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Marie-Noelle Celerier , Peter Szekeres

Analytical computations in relativistic cosmology can be split into two sets: time evolution relating the initial conditions to the observer's light-cone and light propagation to obtain observables. Cosmological perturbation theory in the…

General Relativity and Quantum Cosmology · Physics 2021-01-18 Ermis Mitsou , Giuseppe Fanizza , Nastassia Grimm , Jaiyul Yoo

We study a fundamental issue in cosmology: Whether we can rely on a cosmological model to understand the real history of the Universe. This fundamental, still unresolved issue is often called the ``model-fitting problem (or averaging…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Masafumi Seriu

In many astronomical problems one often needs to determine the upper and/or lower boundary of a given data set. An automatic and objective approach consists in fitting the data using a generalised least-squares method, where the function to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 N. Cardiel

Multi-messenger astronomy is becoming the key to understanding the Universe from a comprehensive perspective. In most cases, the data and the technology are already in place, therefore it is important to provide an easily-accessible package…

Instrumentation and Methods for Astrophysics · Physics 2015-12-07 M. Pilia , A. Trois , A. P. Pellizzoni , M. Bachetti , G. Piano , A. Poddighe , E. Egron , M. N. Iacolina , A. Melis , R. Concu , A. Possenti , D. Perrodin

We propose a novel measure of statistical depth, the metric spatial depth, for data residing in an arbitrary metric space. The measure assigns high (low) values for points located near (far away from) the bulk of the data distribution,…

Statistics Theory · Mathematics 2023-06-19 Joni Virta