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point (Definition)

In The Elements, Euclid defines a point as that which has no part.

In a vector space, an affine space, or, more generally, an incidence geometry, a point is a zero dimensional object.

In a projective geometry, a point is a one-dimensional subspace of the vector space underlying the projective geometry.

In a topology, a point is an element of a topological space.

Note that there is also the possibility for a point-free approach to geometry in which points are not assumed as a primitive. Instead, points are defined by suitable abstraction processes. (See point-free geometry.)



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"point" is owned by Wkbj79. [ full author list (3) ]
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Cross-references: point-free geometry, primitive, geometry, topology, subspace, projective geometry, incidence geometry, affine space, vector space
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This is version 11 of point, born on 2006-07-24, modified 2007-01-16.
Object id is 8173, canonical name is Point.
Accessed 7383 times total.

Classification:
AMS MSC51-00 (Geometry :: General reference works )
 54-00 (General topology :: General reference works )
 15-00 (Linear and multilinear algebra; matrix theory :: General reference works )

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point by Wkbj79 on 2006-07-24 20:39:22
While reading Mathprof's entry "metacompact", I was surprised to notice that the word "point" had no link. I was curious enough to look at the TeX code and was surprised to find that he had not supressed a link.

After looking around on PM to be sure that "point" really was not an entry, I decided that it would be a good idea to have a definition of it. This is my humble and modest beginning. I am quite sure that the word "point" has many different definitions in many different areas of mathematics, and I would appreciate it if you would add them. Thanks.

Warren
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