Concept

Completeness of the real numbers

Completeness is a property of the real numbers that, intuitively, implies that there are no "gaps" (in Dedekind's terminology) or "missing points" in the real number line. This contrasts with the rational numbers, whose corresponding number line has a "gap" at each irrational value. In the decimal number system, completeness is equivalent to the statement that any infinite string of decimal digits is actually a decimal representation for some real number. Depending on the construction of the real numbers used, completeness may take the form of an axiom (the completeness axiom), or may be a theorem proven from the construction. There are many equivalent forms of completeness, the most prominent being Dedekind completeness and Cauchy completeness (completeness as a metric space). The real numbers can be defined synthetically as an ordered field satisfying some version of the completeness axiom. Different versions of this axiom are all equivalent in the sense that any ordered field that satisfies one form of completeness satisfies all of them, apart from Cauchy completeness and nested intervals theorem, which are strictly weaker in that there are non Archimedean fields that are ordered and Cauchy complete. When the real numbers are instead constructed using a model, completeness becomes a theorem or collection of theorems. Least-upper-bound property The least-upper-bound property states that every nonempty subset of real numbers having an upper bound must have a least upper bound (or supremum) in the set of real numbers. The rational number line Q does not have the least upper bound property. An example is the subset of rational numbers This set has an upper bound. However, this set has no least upper bound in Q: the least upper bound as a subset of the reals would be √2, but it does not exist in Q. For any upper bound x ∈ Q, there is another upper bound y ∈ Q with y < x. For instance, take x = 1.5, then x is certainly an upper bound of S, since x is positive and x^2 = 2.25 ≥ 2; that is, no element of S is larger than x.

Source officielle

https://en.wikipedia.org/wiki/Completeness_of_the_real_numbers

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Cours associés (18)

CS-101: Advanced information, computation, communication I

Discrete mathematics is a discipline with applications to almost all areas of study. It provides a set of indispensable tools to computer science in particular. This course reviews (familiar) topics as diverse as mathematical reasoning, combinatorics, disc ...

MSE-305: Introduction to atomic-scale modeling

This course provides an introduction to the modeling of matter at the atomic scale, using interactive Jupyter notebooks to see several of the core concepts of materials science in action. ...

PHYS-100: Physique avancée I (mécanique)

La Physique Générale I (avancée) couvre la mécanique du point et du solide indéformable. Apprendre la mécanique, c'est apprendre à mettre sous forme mathématique un phénomène physique, en modélisant la situation et appliquant les lois de la physique. ...

Afficher plus

Séances de cours associées (32)

Propriétés des nombres réels

Explique les propriétés des sous-ensembles de nombres réels, y compris Supremum, Infimum, intervalles, ensembles ouverts et ensembles fermés.

Valeur absolue et intervalles

Introduit la valeur absolue, les intervalles, l'inégalité des triangles et les nombres complets dans le plan complexe.

Introduction aux nombres réels

Présente les propriétés et la structure des nombres réels, en mettant l'accent sur l'exhaustivité et la propriété archimédienne.

Afficher plus

Publications associées (3)

Models of Random Spanning Trees

There are numerous randomized algorithms to generate spanning trees in a given ambient graph; several target the uniform distribution on trees (UST), while in practice the fastest and most frequently used draw random weights on the edges and then employ a greedy algorithm to choose the minimum‐weight spanning tree (MST). Though MST is a workhorse in applications, the mathematical properties of random MST are far less explored than those of UST. In this paper we develop tools for the quantitative study of ra

Wiley2026

The integration theory of curved absolute L∞-algebras

In this article, we introduce the notion of a curved absolute -algebra, a structure that behaves like a curved -algebra where all infinite sums of operations are well-defined by definition. We develop their integration theory by introducing two new methods ...

Elsevier BV2024

Curved operadic calculus

Curved algebras are a generalization of differential graded algebras which have found numerous applications recently. The goal of this foundational arti cle is to introduce the notion of a curved operad, and to develop the operadic calculus at this new lev ...

Societe Mathematique de France2024

Graph Chat

Chattez avec Graph Search

Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.

AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.

Source officielle

https://en.wikipedia.org/wiki/Completeness_of_the_real_numbers

À propos de ce résultat

Cours associés (18)

CS-101: Advanced information, computation, communication I

MSE-305: Introduction to atomic-scale modeling

This course provides an introduction to the modeling of matter at the atomic scale, using interactive Jupyter notebooks to see several of the core concepts of materials science in action. ...

PHYS-100: Physique avancée I (mécanique)

Afficher plus

Séances de cours associées (32)

Propriétés des nombres réels

Explique les propriétés des sous-ensembles de nombres réels, y compris Supremum, Infimum, intervalles, ensembles ouverts et ensembles fermés.

Valeur absolue et intervalles

Introduit la valeur absolue, les intervalles, l'inégalité des triangles et les nombres complets dans le plan complexe.

Introduction aux nombres réels

Présente les propriétés et la structure des nombres réels, en mettant l'accent sur l'exhaustivité et la propriété archimédienne.

Afficher plus

Publications associées (3)

Models of Random Spanning Trees

Wiley2026

The integration theory of curved absolute L∞-algebras

Elsevier BV2024

Curved operadic calculus

Societe Mathematique de France2024

Personnes associées (10)

Viktor Kuncak

Viktor Kunčak joined EPFL in 2007, after receiving a PhD degree from MIT. Since then has been leading the Laboratory for Automated Reasoning and Analysis and supervised at least 12 completed PhD theses. His works on languages, algorithms and systems for verification and automated reasoning. He served as an initiator and one of the coordinators of a European network (COST action) in the area of automated reasoning, verification, and synthesis. In 2012 he received a 5-year single-investigator European Research Council (ERC) grant of 1.5M EUR. His invited talks include those at Lambda Days, Scala Days, NFM, LOPSTR, SYNT, ICALP, CSL, RV, VMCAI, and SMT. A paper on test generation he co-authored received an ACM SIGSOFT distinguished paper award at ICSE. A PLDI paper he co-authored was published in the Communications of the ACM as a Research Highlight article. His Google Scholar profile reports an over-approximate H-index of 38. He was an associate editor of ACM Transactions on Programming Languages and Systems (TOPLAS) and served as a co-chair of conferences on Computer-Aided Verification (CAV), Formal Methods in Computer Aided Design (FMCAD), Workshop on Synthesis (SYNT), and Verification, Model Checking, and Abstract Interpretation (VMCAI). At EPFL he teaches courses on functional and parallel programming, compilers, and verification. He has co-taught the MOOC "Parallel Programming" that was visited by over 100'000 learners and completed by thousands of students from all over the world.

Bruno Marchand

Enseignement et PhD A dirigé les thèses EPFL de Ali Aziza, Philippe Mivelaz, Habib Sayah, Nicolas Bassand, Frédéric Frank, Antigoni Katsakou, Olga Moatsou, Joana Gouveia Alves, Marta Meira Brandão, Jean-Claude Girard, Sonia Curnier, Jean-Denis Thiry

Michael Christoph Gastpar

Michael Gastpar is a (full) Professor at EPFL. From 2003 to 2011, he was a professor at the University of California at Berkeley, earning his tenure in 2008. He received his Dipl. El.-Ing. degree from ETH Zürich, Switzerland, in 1997 and his MS degree from the University of Illinois at Urbana-Champaign, IL, USA, in 1999. He defended his doctoral thesis at EPFL on Santa Claus day, 2002. He was also a (full) Professor at Delft University of Technology, The Netherlands. His research interests are in network information theory and related coding and signal processing techniques, with applications to sensor networks and neuroscience. He is a Fellow of the IEEE. He is the co-recipient of the 2013 Communications Society & Information Theory Society Joint Paper Award. He was an Information Theory Society Distinguished Lecturer (2009-2011). He won an ERC Starting Grant in 2010, an Okawa Foundation Research Grant in 2008, an NSF CAREER award in 2004, and the 2002 EPFL Best Thesis Award. He has served as an Associate Editor for Shannon Theory for the IEEE Transactions on Information Theory (2008-11), and as Technical Program Committee Co-Chair for the 2010 International Symposium on Information Theory, Austin, TX.

Friedrich Eisenbrand

Enseignement et PhD Doctorant·es actuel·les Ruben Manuel Skorupinski, Neta Singer, Lukas Vogl, Jiaye Wei A dirigé les thèses EPFL de Thomas Rothvoss, Nicolai Hähnle, Martin Niemeier, Adrian Aloysius Bock, Carsten Moldenhauer, Alfonso Bolívar Cevallos Manzano, Manuel Francesco Aprile, Igor Malinovic, Christoph Hunkenschröder, Moritz Andreas Venzin, Jana Tabea Cslovjecsek A co-dirigé les thèses EPFL de Puck van Gerwen Cours Algèbre linéaire avancée II - diagonalisation MATH-115(a) L'objectif

Barbara Jobstmann

Expertise Automatic synthesis and repair of reactive programsQuantitative analysis and synthesisFormal verification and modelling of systems (e.g., hardware designs, transactional memories, biological systems, business processes,...) About me I am a lecturer for the school of computer and communication sciences and I organise different outreach activities (for more details visit our IC Declic Summer School Webpage). In addition, I work for Cadence Design Systems.My research focused on the development of rel

Francesco Mondada

Voir la page en anglais

Philippe Müllhaupt

Expertise Commande non linéaireThéorie de la commandeMécanique généraleSystèmes dynamiquesStatistique Mission Offrir une formation technique et scientifique rigoureuse en commande non linéaire, en mécanique classique et en théorie statistique Travail en cours Chercheur et enseignant dans les domaines de l'automatique, la statistique, les systèmes dyanmiques et la mécanique classique. E MSc. et BSc. en génie électrique (EPFL, 1993) DEA en Automatique et Traitement du Signal (Paris VI, 1994) PhD en Automa

Thomas Mountford

D'origine britannique, né en 1961. Il a reçu la bourse présidentielle des jeunes investisseurs (Presidential Young Investigator Grant) en 1990 et le prix de la Fraternité Sloan (Sloan Fellowship) en 1991. Son travail montre que les valeurs critiques d'une classe large de de systèmes de particules proches sont égales à 1, et que, suite à plusieurs travaux sur la trajectoire du mouvement brownien, incluant une simulation numérique, le nombre d'îlots browniens en 2 dimensions tend vers l'infini quand leurs tailles tendent vers 0. Il reçoit le prix Rosenbaum en 1993 lui ouvrant ainsi les portes du Isaac Newton Institute à Cambridge. Il est également décoré par le prix Rollo Davidson en 1995 et nommé membre honoraire de l'Institute of Mathematical Statistics en 2001. Assistant Profeseur de Mathematique a UCLA 1987- 1991 Associate Professeur de Mathematique a UCLA 1991-1993 Professeur de Mathematique a UCLA 1993-2001 Professeur Departement de mathématiques, EPFL dès 2001

Emre Telatar

Enseignement et PhD Doctorant·es actuel·les Serhat Emre Coban, Adway Girish, Ryan Yuanqing Song A dirigé les thèses EPFL de Aslan Tchamkerten, Stéphane Musy, Sibi Raj Bhaskaran Pillai, Robert Konsbruck, Dinkar Vasudevan, Eren Sasoglu, Mohammad Karzand, Alla Merzakreeva, Mine Alsan, Marc Desgroseilliers, Mani Bastani Parizi, Rajai Nasser, Serj Haddad, Elie Najm, Yunus Inan, Reka Inovan, Pierre Quinton A co-dirigé les thèses EPFL de Prasenjit Dey, Etienne Perron, Ayfer Özgür Aydin Cours Information theory

Volkan Cevher

Volkan Cevher received the B.Sc. (valedictorian) in electrical engineering from Bilkent University in Ankara, Turkey, in 1999 and the Ph.D. in electrical and computer engineering from the Georgia Institute of Technology in Atlanta, GA in 2005. He was a Research Scientist with the University of Maryland, College Park from 2006-2007 and also with Rice University in Houston, TX, from 2008-2009. Currently, he is an Associate Professor at the Swiss Federal Institute of Technology Lausanne and a Faculty Fellow in the Electrical and Computer Engineering Department at Rice University. His research interests include machine learning, signal processing theory, optimization theory and methods, and information theory. Dr. Cevher is an ELLIS fellow and was the recipient of the Google Faculty Research award in 2018, the IEEE Signal Processing Society Best Paper Award in 2016, a Best Paper Award at CAMSAP in 2015, a Best Paper Award at SPARS in 2009, and an ERC CG in 2016 as well as an ERC StG in 2011.

Concepts associés (5)

Linear continuum

In the mathematical field of order theory, a continuum or linear continuum is a generalization of the real line. Formally, a linear continuum is a linearly ordered set S of more than one element that is densely ordered, i.e., between any two distinct elements there is another (and hence infinitely many others), and complete, i.e., which "lacks gaps" in the sense that every nonempty subset with an upper bound has a least upper bound.

Propriété de la borne supérieure

En mathématiques, un ensemble ordonné est dit posséder la propriété de la borne supérieure si tous ses sous-ensembles non vides et majorés possèdent une borne supérieure. De même, un ensemble ordonné possède la propriété de la borne inférieure si tous ses sous-ensembles non vides et minorés possèdent une borne inférieure. Il s'avère que ces deux propriétés sont équivalentes. On dit aussi parfois qu'un ensemble possédant la propriété de la borne supérieure est Dedekind complet. Soit un ensemble ordonné (partiellement ou totalement).

Théorème des valeurs intermédiaires

vignette|Illustration du théorème des valeurs intermédiaires : si f est une fonction continue sur l'intervalle [a ; b], alors elle prend toutes les valeurs comprises entre f(a) et f(b) au moins une fois. Ici la valeur s est prise trois fois. En mathématiques, le théorème des valeurs intermédiaires (abrégé en TVI), parfois appelé théorème de Bolzano, est un résultat important en analyse et concerne des fonctions continues sur un intervalle.

Afficher plus

MOOCs associés (1)

Information, Calcul, Communication: Introduction à la pensée informatique

Dans une première partie, nous étudierons d’abord comment résoudre de manière très concrète un problème au moyen d’un algorithme, ce qui nous amènera dans un second temps à une des grandes questions de l’informatique théorique moderne. La seconde partie du cours sera quant à elle consacrée à l’information est la communication : nous passerons en revue plusieurs sujets, comme la représentation de l'information, le traitement des signaux, la compression de données, la communication et la cryptographie.

Notebooks associés (1)

Understanding and Plotting the Discrete Fourier Transform (DFT)

Plotting the DFT[1]¶

                                      [2]Paolo Prandoni, [3]LCAV, EPFL

In this notebook we will look at the practical issues associated to plotting the DFT and in particular the DFT of real-world signals. We will examine how to map the DFT coefficients to real-world frequencies and we will investigate the frequency resolution of the DFT and the effects of zero padding. In [1]:

first our usual bookkeeping

%matplotlib inline import matplotlib import matplotlib.p

Personnes associées (10)

Viktor Kuncak

Bruno Marchand

Michael Christoph Gastpar

Friedrich Eisenbrand

Barbara Jobstmann

Francesco Mondada

Voir la page en anglais