Aleph0

Aleph-zéro

Cet article court présente un sujet plus amplement développé ici : Aleph (nombre) et Ensemble dénombrable.

Le cardinal de l'ensemble des entiers naturels, et donc par équipotence, le cardinal de n'importe quel ensemble dénombrable, est noté \aleph_0 et se lit Aleph-zéro, c'est le premier dans la suite indexée par les ordinaux des alephs, une suite d'ordinaux définie par Georg Cantor pour représenter tous les cardinaux infinis.

  • Portail des mathématiques Portail des mathématiques
Ce document provient de « Aleph-z%C3%A9ro ».

Wikimedia Foundation. 2010.

Contenu soumis à la licence CC-BY-SA. Source : Article Aleph0 de Wikipédia en français (auteurs)

Regardez d'autres dictionnaires:

  • Hilbert's second problem — In mathematics, Hilbert s second problem was posed by David Hilbert in 1900 as one of his 23 problems. It asks for a proof that arithmetic of real numbers is consistent.In the 1930s, Kurt Gödel and Gerhard Gentzen proved results that cast new… …   Wikipedia

  • Australoid — The Australoid race is a broad racial classification. The concept s existence is based on the typological method of racial classification. [O Neil, Dennis. Biological Anthropology Terms. 2006. May 13, 2007. Palomar College. [http://anthro.palomar …   Wikipedia

  • Euclid's Elements — (Greek: polytonic|Στοιχεῖα) is a mathematical and geometric treatise consisting of 13 books written by the Greek mathematician Euclid in Alexandria circa 300 BC. It comprises a collection of definitions, postulates (axioms), propositions… …   Wikipedia

  • Ptolemy's theorem — In mathematics, Ptolemy s theorem is a relation in Euclidean geometry between the four sides and two diagonals or chords of a cyclic quadrilateral. The theorem is named after the Greek astronomer and mathematician Ptolemy (Claudius Ptolemaeus).If …   Wikipedia

  • Reaction to Darwin's theory — This article deals with Darwin s life during the period from 1859 to 1861, including immediate reactions to his publication of The Origin of Species . For events leading up to this period, see inception of Darwin s theory, development of Darwin s …   Wikipedia

  • Nordic race — Meyers Blitz Lexikon (Leipzig, 1932) shows a famous German war hero (Karl von Müller) as an example of the Nordic type. The Nordic race is one of the racial subcategories into which the Caucasian race was divided by anthropologists in the first… …   Wikipedia

  • Quadrumana — and Bimana form an obsolete division of the primates: the Quadrumana are primates with four hands (two attached to the arms and two attached to the legs), and the Bimana being those with two hands and two feet. The attempted division of… …   Wikipedia

  • Mongoloid race — The term Mongoloid is a variation of the word Mongol , meaning Mongol like . It has been coined as a racial category to describe the distinctive appearance of East Asian peoples. Today it is most used in discussions of human prehistory,… …   Wikipedia

  • Afterwissenschaft — Pseudowissenschaft (griech. ψεύδω, pseudo, „ich täusche vor“) ist ein Begriff für Behauptungen, Theorien, Praktiken und Institutionen, die sich den Anschein der Wissenschaftlichkeit geben, ohne diesen Anspruch zu erfüllen. Der Gebrauch dieses… …   Deutsch Wikipedia

  • Pseudowissenschaftlich — Pseudowissenschaft (griech. ψεύδω, pseudo, „ich täusche vor“) ist ein Begriff für Behauptungen, Theorien, Praktiken und Institutionen, die sich den Anschein der Wissenschaftlichkeit geben, ohne diesen Anspruch zu erfüllen. Der Gebrauch dieses… …   Deutsch Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”