File:Topological space examples.svg

Summary

Description
English: Examples and non-examples of topological spaces, based roughly on Figures 12.1 and 12.2 from Munkres' Introduction to Topology. The 6 examples are subsets of the power set of {1,2,3}, with the small circle in the upper left of each denoting the empty set, and in reading order they are:
  • {{}, {1,2,3}} (the trivial topology)
  • {{}, {1}, {1,2,3}}
  • {{}, {1}, {2}, {1,2}, {1,2,3}}
  • {{}, {2}, {1,2}, {2,3}, {1,2,3}}
  • {{}, {2}, {3}, {1,2,3}} (not a topology, because {2} and {3} are in the topology but their union {2,3} is not)
  • {{}, {1,2}, {2,3}, {1,2,3}} (not a topology, because {1,2} and {2,3} are in the topology but their intersection {2} is not)
Deutsch: Beispiele und Gegenspiele zu topologischen Räumen, die grob den Abbildungen 12.1 und 12.2 aus dem Buch Introduction to Topology von Munkres entsprechen. Die sech Beispiele sind Teilmenge der Potenzmenge von {1,2,3}. Der kleine Kreis in den Beispielen oben links bezeichnet die leere Menge. Im Detail lauten die Beispiele dann:
  • {{}, {1,2,3}} (triviale Topologie)
  • {{}, {1}, {1,2,3}}
  • {{}, {1}, {2}, {1,2}, {1,2,3}}
  • {{}, {2}, {1,2}, {2,3}, {1,2,3}}
  • {{}, {2}, {3}, {1,2,3}} (kein topologischer Raum, da die Mengen {2} und {3} zur Topologie gehören, aber ihre Vereinigung {2,3} nicht)
  • {{}, {1,2}, {2,3}, {1,2,3}} (kein topologischer Raum, da die Mengen {1,2} und {2,3} zur Topologie gehören, aber der Schnitt {2} der beiden nicht)
Español: Ejemplos y contraejemplos de espacios topológicos basados, fundamentalmente, en las Figuras 12.1 y 12.2 del libro "Introduction to Topology" de Munkres. Los seis ejemplos son subconjuntos del conjunto potencia {1,2,3}, donde el círculo pequeño en la esquina superior izquierda de cada figura representa el conjunto vacío, y que en orden de lectura son
  • {{}, {1,2,3}} (topología trivial)
  • {{}, {1}, {1,2,3}}
  • {{}, {1}, {2}, {1,2}, {1,2,3}}
  • {{}, {2}, {1,2}, {2,3}, {1,2,3}}
  • {{}, {2}, {3}, {1,2,3}} (no es topológico porque {2} y {3} se encuentran en la topología, pero su unión {2,3} no)
  • {{}, {1,2}, {2,3}, {1,2,3}} (no es topológico porque {1,2} y {2,3} se encuentran en la topología, pero su intersección {2} no)
Date
Source Own work
Author Dcoetzee

Licensing

Public domain I, the copyright holder of this work, release this work into the public domain. This applies worldwide.
In some countries this may not be legally possible; if so:
I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.
Category:Self-published work#Topological%20space%20examples.svgCategory:PD-self#Topological%20space%20examples.svg Category:Topology
Category:PD-self Category:Self-published work Category:Topology