Geometric GSI’19 Science of Information Toulouse, 27Th - 29Th August 2019
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Riemannian Geometry and the General Theory of Relativity
University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 1967 Riemannian geometry and the general theory of relativity Marie McBride Vanisko The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Vanisko, Marie McBride, "Riemannian geometry and the general theory of relativity" (1967). Graduate Student Theses, Dissertations, & Professional Papers. 8075. https://scholarworks.umt.edu/etd/8075 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. p m TH3 OmERAl THEORY OF RELATIVITY By Marie McBride Vanisko B.A., Carroll College, 1965 Presented in partial fulfillment of the requirements for the degree of Master of Arts UNIVERSITY OF MOKT/JTA 1967 Approved by: Chairman, Board of Examiners D e a ^ Graduante school V AUG 8 1967, Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. V W Number: EP38876 All rights reserved INFORMATION TO ALL USERS The quality of this reproduotion is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missir^ pages, these will be noted. Also, if matedal had to be removed, a note will indicate the deletion. UMT Oi*MMtion neiitNna UMi EP38876 Published ProQuest LLQ (2013). -
Riemannian Geometry Learning for Disease Progression Modelling Maxime Louis, Raphäel Couronné, Igor Koval, Benjamin Charlier, Stanley Durrleman
Riemannian geometry learning for disease progression modelling Maxime Louis, Raphäel Couronné, Igor Koval, Benjamin Charlier, Stanley Durrleman To cite this version: Maxime Louis, Raphäel Couronné, Igor Koval, Benjamin Charlier, Stanley Durrleman. Riemannian geometry learning for disease progression modelling. 2019. hal-02079820v2 HAL Id: hal-02079820 https://hal.archives-ouvertes.fr/hal-02079820v2 Preprint submitted on 17 Apr 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Riemannian geometry learning for disease progression modelling Maxime Louis1;2, Rapha¨elCouronn´e1;2, Igor Koval1;2, Benjamin Charlier1;3, and Stanley Durrleman1;2 1 Sorbonne Universit´es,UPMC Univ Paris 06, Inserm, CNRS, Institut du cerveau et de la moelle (ICM) 2 Inria Paris, Aramis project-team, 75013, Paris, France 3 Institut Montpelli`erainAlexander Grothendieck, CNRS, Univ. Montpellier Abstract. The analysis of longitudinal trajectories is a longstanding problem in medical imaging which is often tackled in the context of Riemannian geometry: the set of observations is assumed to lie on an a priori known Riemannian manifold. When dealing with high-dimensional or complex data, it is in general not possible to design a Riemannian geometry of relevance. In this paper, we perform Riemannian manifold learning in association with the statistical task of longitudinal trajectory analysis. -
An Introduction to Riemannian Geometry with Applications to Mechanics and Relativity
An Introduction to Riemannian Geometry with Applications to Mechanics and Relativity Leonor Godinho and Jos´eNat´ario Lisbon, 2004 Contents Chapter 1. Differentiable Manifolds 3 1. Topological Manifolds 3 2. Differentiable Manifolds 9 3. Differentiable Maps 13 4. Tangent Space 15 5. Immersions and Embeddings 22 6. Vector Fields 26 7. Lie Groups 33 8. Orientability 45 9. Manifolds with Boundary 48 10. Notes on Chapter 1 51 Chapter 2. Differential Forms 57 1. Tensors 57 2. Tensor Fields 64 3. Differential Forms 66 4. Integration on Manifolds 72 5. Stokes Theorem 75 6. Orientation and Volume Forms 78 7. Notes on Chapter 2 80 Chapter 3. Riemannian Manifolds 87 1. Riemannian Manifolds 87 2. Affine Connections 94 3. Levi-Civita Connection 98 4. Minimizing Properties of Geodesics 104 5. Hopf-Rinow Theorem 111 6. Notes on Chapter 3 114 Chapter 4. Curvature 115 1. Curvature 115 2. Cartan’s Structure Equations 122 3. Gauss-Bonnet Theorem 131 4. Manifolds of Constant Curvature 137 5. Isometric Immersions 144 6. Notes on Chapter 4 150 1 2 CONTENTS Chapter 5. Geometric Mechanics 151 1. Mechanical Systems 151 2. Holonomic Constraints 160 3. Rigid Body 164 4. Non-Holonomic Constraints 177 5. Lagrangian Mechanics 186 6. Hamiltonian Mechanics 194 7. Completely Integrable Systems 203 8. Notes on Chapter 5 209 Chapter 6. Relativity 211 1. Galileo Spacetime 211 2. Special Relativity 213 3. The Cartan Connection 223 4. General Relativity 224 5. The Schwarzschild Solution 229 6. Cosmology 240 7. Causality 245 8. Singularity Theorem 253 9. Notes on Chapter 6 263 Bibliography 265 Index 267 CHAPTER 1 Differentiable Manifolds This chapter introduces the basic notions of differential geometry. -
Riemannian Geometry and Multilinear Tensors with Vector Fields on Manifolds Md
International Journal of Scientific & Engineering Research, Volume 5, Issue 9, September-2014 157 ISSN 2229-5518 Riemannian Geometry and Multilinear Tensors with Vector Fields on Manifolds Md. Abdul Halim Sajal Saha Md Shafiqul Islam Abstract-In the paper some aspects of Riemannian manifolds, pseudo-Riemannian manifolds, Lorentz manifolds, Riemannian metrics, affine connections, parallel transport, curvature tensors, torsion tensors, killing vector fields, conformal killing vector fields are focused. The purpose of this paper is to develop the theory of manifolds equipped with Riemannian metric. I have developed some theorems on torsion and Riemannian curvature tensors using affine connection. A Theorem 1.20 named “Fundamental Theorem of Pseudo-Riemannian Geometry” has been established on Riemannian geometry using tensors with metric. The main tools used in the theorem of pseudo Riemannian are tensors fields defined on a Riemannian manifold. Keywords: Riemannian manifolds, pseudo-Riemannian manifolds, Lorentz manifolds, Riemannian metrics, affine connections, parallel transport, curvature tensors, torsion tensors, killing vector fields, conformal killing vector fields. —————————— —————————— I. Introduction (c) { } is a family of open sets which covers , that is, 푖 = . Riemannian manifold is a pair ( , g) consisting of smooth 푈 푀 manifold and Riemannian metric g. A manifold may carry a (d) ⋃ is푈 푖푖 a homeomorphism푀 from onto an open subset of 푀 ′ further structure if it is endowed with a metric tensor, which is a 푖 . 푖 푖 휑 푈 푈 natural generation푀 of the inner product between two vectors in 푛 ℝ to an arbitrary manifold. Riemannian metrics, affine (e) Given and such that , the map = connections,푛 parallel transport, curvature tensors, torsion tensors, ( ( ) killingℝ vector fields and conformal killing vector fields play from푖 푗 ) to 푖 푗 is infinitely푖푗 −1 푈 푈 푈 ∩ 푈 ≠ ∅ 휓 important role to develop the theorem of Riemannian manifolds. -
A Hybrid Global Optimization Method: the One-Dimensional Case Peiliang Xu
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Journal of Computational and Applied Mathematics 147 (2002) 301–314 www.elsevier.com/locate/cam A hybrid global optimization method: the one-dimensional case Peiliang Xu Disaster Prevention Research Institute, Kyoto University, Uji, Kyoto 611-0011, Japan Received 20 February 2001; received in revised form 4 February 2002 Abstract We propose a hybrid global optimization method for nonlinear inverse problems. The method consists of two components: local optimizers and feasible point ÿnders. Local optimizers have been well developed in the literature and can reliably attain the local optimal solution. The feasible point ÿnder proposed here is equivalent to ÿnding the zero points of a one-dimensional function. It warrants that local optimizers either obtain a better solution in the next iteration or produce a global optimal solution. The algorithm by assembling these two components has been proved to converge globally and is able to ÿnd all the global optimal solutions. The method has been demonstrated to perform excellently with an example having more than 1 750 000 local minima over [ −106; 107].c 2002 Elsevier Science B.V. All rights reserved. Keywords: Interval analysis; Hybrid global optimization 1. Introduction Many problems in science and engineering can ultimately be formulated as an optimization (max- imization or minimization) model. In the Earth Sciences, we have tried to collect data in a best way and then to extract the information on, for example, the Earth’s velocity structures and=or its stress=strain state, from the collected data as much as possible. -
Riemann's Contribution to Differential Geometry
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Historia Mathematics 9 (1982) l-18 RIEMANN'S CONTRIBUTION TO DIFFERENTIAL GEOMETRY BY ESTHER PORTNOY UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN, URBANA, IL 61801 SUMMARIES In order to make a reasonable assessment of the significance of Riemann's role in the history of dif- ferential geometry, not unduly influenced by his rep- utation as a great mathematician, we must examine the contents of his geometric writings and consider the response of other mathematicians in the years immedi- ately following their publication. Pour juger adkquatement le role de Riemann dans le developpement de la geometric differentielle sans etre influence outre mesure par sa reputation de trks grand mathematicien, nous devons &udier le contenu de ses travaux en geometric et prendre en consideration les reactions des autres mathematiciens au tours de trois an&es qui suivirent leur publication. Urn Riemann's Einfluss auf die Entwicklung der Differentialgeometrie richtig einzuschZtzen, ohne sich von seinem Ruf als bedeutender Mathematiker iiberm;issig beeindrucken zu lassen, ist es notwendig den Inhalt seiner geometrischen Schriften und die Haltung zeitgen&sischer Mathematiker unmittelbar nach ihrer Verijffentlichung zu untersuchen. On June 10, 1854, Georg Friedrich Bernhard Riemann read his probationary lecture, "iber die Hypothesen welche der Geometrie zu Grunde liegen," before the Philosophical Faculty at Gdttingen ill. His biographer, Dedekind [1892, 5491, reported that Riemann had worked hard to make the lecture understandable to nonmathematicians in the audience, and that the result was a masterpiece of presentation, in which the ideas were set forth clearly without the aid of analytic techniques. -
Arxiv:1804.07332V1 [Math.OC] 19 Apr 2018
Juniper: An Open-Source Nonlinear Branch-and-Bound Solver in Julia Ole Kr¨oger,Carleton Coffrin, Hassan Hijazi, Harsha Nagarajan Los Alamos National Laboratory, Los Alamos, New Mexico, USA Abstract. Nonconvex mixed-integer nonlinear programs (MINLPs) rep- resent a challenging class of optimization problems that often arise in engineering and scientific applications. Because of nonconvexities, these programs are typically solved with global optimization algorithms, which have limited scalability. However, nonlinear branch-and-bound has re- cently been shown to be an effective heuristic for quickly finding high- quality solutions to large-scale nonconvex MINLPs, such as those arising in infrastructure network optimization. This work proposes Juniper, a Julia-based open-source solver for nonlinear branch-and-bound. Leverag- ing the high-level Julia programming language makes it easy to modify Juniper's algorithm and explore extensions, such as branching heuris- tics, feasibility pumps, and parallelization. Detailed numerical experi- ments demonstrate that the initial release of Juniper is comparable with other nonlinear branch-and-bound solvers, such as Bonmin, Minotaur, and Knitro, illustrating that Juniper provides a strong foundation for further exploration in utilizing nonlinear branch-and-bound algorithms as heuristics for nonconvex MINLPs. 1 Introduction Many of the optimization problems arising in engineering and scientific disci- plines combine both nonlinear equations and discrete decision variables. Notable examples include the blending/pooling problem [1,2] and the design and opera- tion of power networks [3,4,5] and natural gas networks [6]. All of these problems fall into the class of mixed-integer nonlinear programs (MINLPs), namely, minimize: f(x; y) s.t. -
A SPACETIME GEOMETRODYNAMIC MODEL (GDM) of the PHYSICAL REALITY Shlomo Barak
A SPACETIME GEOMETRODYNAMIC MODEL (GDM) OF THE PHYSICAL REALITY Shlomo Barak To cite this version: Shlomo Barak. A SPACETIME GEOMETRODYNAMIC MODEL (GDM) OF THE PHYSICAL REALITY. 2018. hal-01935260 HAL Id: hal-01935260 https://hal.archives-ouvertes.fr/hal-01935260 Preprint submitted on 14 Jan 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. A SPACETIME GEOMETRODYNAMIC MODEL (GDM) Shlomo Barak Shlomo Barak OF THE PHYSICAL REALITY Shlomo Barak II The Book of the GDM A Realization of Einstein’s Vision Dr. Shlomo Barak Editor: Roger M. Kaye A collection of 18 papers published Nov 2016 to Nov 2018. III A. Einstein (1933) …. the axiomatic basis of theoretical physics cannot be extracted from experience but must be freely invented… Copyright © 2018 Shlomo Barak The right of Shlomo Barak to be identified as the author of this work has been asserted by him. All rights reserved. No part of this book may be reproduced or copied in any form or by any means, graphic, electronic or mechanical, or otherwise, including photocopying, recording, or information retrieval systems - without written permission. ISBN 978-965-90727-1-2 IV This GDM book is a collection of 18 papers published from November 2016 to November 2018. -
Global Optimization, the Gaussian Ensemble, and Universal Ensemble Equivalence
Probability, Geometry and Integrable Systems MSRI Publications Volume 55, 2007 Global optimization, the Gaussian ensemble, and universal ensemble equivalence MARIUS COSTENIUC, RICHARD S. ELLIS, HUGO TOUCHETTE, AND BRUCE TURKINGTON With great affection this paper is dedicated to Henry McKean on the occasion of his 75th birthday. ABSTRACT. Given a constrained minimization problem, under what condi- tions does there exist a related, unconstrained problem having the same mini- mum points? This basic question in global optimization motivates this paper, which answers it from the viewpoint of statistical mechanics. In this context, it reduces to the fundamental question of the equivalence and nonequivalence of ensembles, which is analyzed using the theory of large deviations and the theory of convex functions. In a 2000 paper appearing in the Journal of Statistical Physics, we gave nec- essary and sufficient conditions for ensemble equivalence and nonequivalence in terms of support and concavity properties of the microcanonical entropy. In later research we significantly extended those results by introducing a class of Gaussian ensembles, which are obtained from the canonical ensemble by adding an exponential factor involving a quadratic function of the Hamiltonian. The present paper is an overview of our work on this topic. Our most important discovery is that even when the microcanonical and canonical ensembles are not equivalent, one can often find a Gaussian ensemble that satisfies a strong form of equivalence with the microcanonical ensemble known as universal equivalence. When translated back into optimization theory, this implies that an unconstrained minimization problem involving a Lagrange multiplier and a quadratic penalty function has the same minimum points as the original con- strained problem. -
1. Introduction
Beichler (1) Preliminary paper for Vigier IX Conference June 2014 MODERN FYSICS PHALLACIES: THE BEST WAY NOT TO UNIFY PHYSICS JAMES E. BEICHLER Research Institute for Paraphysics, Retired P.O. Box 624, Belpre, Ohio 45714 USA [email protected] Too many physicists believe the ‘phallacy’ that the quantum is more fundamental than relativity without any valid supporting evidence, so the earliest attempts to unify physics based on the continuity of relativity have been all but abandoned. This belief is probably due to the wealth of pro-quantum propaganda and general ‘phallacies in fysics’ that were spread during the second quarter of the twentieth century, although serious ‘phallacies’ exist throughout physics on both sides of the debate. Yet both approaches are basically flawed because both relativity and the quantum theory are incomplete and grossly misunderstood as they now stand. Had either side of the quantum versus relativity controversy sought common ground between the two worldviews, total unification would have been accomplished long ago. The point is, literally, that the discrete quantum, continuous relativity, basic physical geometry, theoretical mathematics and classical physics all share one common characteristic that has never been fully explored or explained – a paradoxical duality between a dimensionless point (discrete) and an extended length (continuity) in any dimension – and if the problem of unification is approached from an understanding of how this paradox relates to each paradigm, all of physics and indeed all of science could be unified under a single new theoretical paradigm. Keywords: unification, single field theory, unified field theory, quantized space-time, five-dimensional space-time, quantum, relativity, hidden variables, Einstein, Kaluza, Klein, Clifford 1. -
Riemannian Reading: Using Manifolds to Calculate and Unfold
Eastern Illinois University The Keep Masters Theses Student Theses & Publications 2017 Riemannian Reading: Using Manifolds to Calculate and Unfold Narrative Heather Lamb Eastern Illinois University This research is a product of the graduate program in English at Eastern Illinois University. Find out more about the program. Recommended Citation Lamb, Heather, "Riemannian Reading: Using Manifolds to Calculate and Unfold Narrative" (2017). Masters Theses. 2688. https://thekeep.eiu.edu/theses/2688 This is brought to you for free and open access by the Student Theses & Publications at The Keep. It has been accepted for inclusion in Masters Theses by an authorized administrator of The Keep. For more information, please contact [email protected]. The Graduate School� EA<.TEH.NILLINOIS UNJVER.SITY" Thesis Maintenance and Reproduction Certificate FOR: Graduate Candidates Completing Theses in Partial Fulfillment of the Degree Graduate Faculty Advisors Directing the Theses RE: Preservation, Reproduction, and Distribution of Thesis Research Preserving, reproducing, and distributing thesis research is an important part of Booth Library's responsibility to provide access to scholarship. In order to further this goal, Booth Library makes all graduate theses completed as part of a degree program at Eastern Illinois University available for personal study, research, and other not-for-profit educational purposes. Under 17 U.S.C. § 108, the library may reproduce and distribute a copy without infringing on copyright; however, professional courtesy dictates that permission be requested from the author before doing so. Your signatures affirm the following: • The graduate candidate is the author of this thesis. • The graduate candidate retains the copyright and intellectual property rights associated with the original research, creative activity, and intellectual or artistic content of the thesis. -
Teaching General Relativity
Teaching General Relativity Robert M. Wald Enrico Fermi Institute and Department of Physics The University of Chicago, Chicago, IL 60637, USA February 4, 2008 Abstract This Resource Letter provides some guidance on issues that arise in teaching general relativity at both the undergraduate and graduate levels. Particular emphasis is placed on strategies for presenting the mathematical material needed for the formulation of general relativity. 1 Introduction General Relativity is the theory of space, time, and gravity formulated by Einstein in 1915. It is widely regarded as a very abstruse, mathematical theory and, indeed, until recently it has not generally been regarded as a suitable subject for an undergraduate course. In actual fact, the the mathematical material (namely, differential geometry) needed to attain a deep understanding of general relativity is not particularly difficult and requires arXiv:gr-qc/0511073v1 14 Nov 2005 a background no greater than that provided by standard courses in advanced calculus and linear algebra. (By contrast, considerably more mathematical sophistication is need to provide a rigorous formulation of quantum theory.) Nevertheless, this mathematical material is unfamiliar to most physics students and its application to general relativity goes against what students have been taught since high school (or earlier): namely, that “space” has the natural structure of a vector space. Thus, the mathematical material poses a major challenge to teaching general relativity—particularly for a one-semester course. If one take the time to teach the mathematical material properly, one runs the risk of turning the course into a course on differential geometry and doing very little physics.