Difference between revisions of "Snake-like continuum"
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− | A [[Continuum|continuum]] which, for any | + | {{TEX|done}} |
+ | A [[Continuum|continuum]] which, for any $\epsilon>0$, admits an open covering whose nerve (cf. [[Nerve of a family of sets|Nerve of a family of sets]]) is a finite linear complex. In other words, for any $\epsilon>0$ the continuum must be covered by a finite system $G_n$, $n=1,\ldots,p$, of open sets such that the diameter of each $G_n$ is less than $\epsilon$ and $G_i\cap G_j\neq\emptyset$ if and only if $|i-j|=1$ (such a system is called an $\epsilon$-chain). Every snake-like continuum is irreducible (see [[Irreducible continuum|Irreducible continuum]]) between any pair of its points. Every subcontinuum of a snake-like continuum is snake-like. Two hereditarily-indecomposable snake-like continua (see [[Indecomposable continuum|Indecomposable continuum]]) containing more than one point are homeomorphic; these are known as pseudo-arcs (cf. [[Pseudo-arc|Pseudo-arc]]). Every snake-like continuum is topologically imbeddable in the plane. Any homogeneous snake-like continuum is a pseudo-arc. Every snake-like continuum is the continuous image of a pseudo-arc and the limit of the inverse spectrum of arcs. | ||
====References==== | ====References==== |
Latest revision as of 12:29, 12 April 2014
A continuum which, for any $\epsilon>0$, admits an open covering whose nerve (cf. Nerve of a family of sets) is a finite linear complex. In other words, for any $\epsilon>0$ the continuum must be covered by a finite system $G_n$, $n=1,\ldots,p$, of open sets such that the diameter of each $G_n$ is less than $\epsilon$ and $G_i\cap G_j\neq\emptyset$ if and only if $|i-j|=1$ (such a system is called an $\epsilon$-chain). Every snake-like continuum is irreducible (see Irreducible continuum) between any pair of its points. Every subcontinuum of a snake-like continuum is snake-like. Two hereditarily-indecomposable snake-like continua (see Indecomposable continuum) containing more than one point are homeomorphic; these are known as pseudo-arcs (cf. Pseudo-arc). Every snake-like continuum is topologically imbeddable in the plane. Any homogeneous snake-like continuum is a pseudo-arc. Every snake-like continuum is the continuous image of a pseudo-arc and the limit of the inverse spectrum of arcs.
References
[1] | K. Kuratowski, "Topology" , 2 , Acad. Press (1968) (Translated from French) |
Comments
A snake-like continuum is also called a chainable continuum.
Snake-like continuum. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Snake-like_continuum&oldid=31626