Topological properties on Linear spaces

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Discussion Overview

The discussion revolves around the concept of topological properties in linear spaces, specifically whether subspaces can be considered open subsets when the linear space is treated as a topological space. The scope includes theoretical considerations of topology in vector spaces and the implications of different topological structures.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions the reasonableness of treating subspaces of a linear space as open subsets within a topological framework, noting that the linear space is derived from a known topological space.
  • Another participant argues that subspaces do not form a topology because they fail to meet the axioms of a topological space, specifically mentioning the requirement for the empty set and the union of subspaces.
  • A different participant suggests that it is possible to construct a topology on a linear space, emphasizing that every non-empty set can be made into a topological space, while acknowledging the necessity of considering the original question.
  • One participant points out that while there are many ways to equip a vector space with a topology, the specific choice of open sets proposed by the first participant would not be effective, although they acknowledge that a topology where subspaces are open sets can exist, albeit it may not be interesting.

Areas of Agreement / Disagreement

Participants express differing views on the treatment of subspaces as open sets in topological vector spaces, with no consensus reached on the validity of the initial proposition. The discussion remains unresolved regarding the implications of various topological structures on linear spaces.

Contextual Notes

Limitations include the lack of clarity on specific topological constructions and the implications of different choices of topology on the properties of linear spaces. The discussion does not resolve the mathematical steps necessary to establish a valid topology in this context.

de_brook
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Is it reasonable to work with a linear space whose subspaces are considered as open subsets of the linear space when the linear space is considered as a topological Space? Actually, this linear space is spanned by a topological space with known topology.
 
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The subspaces of a vector space do not form a topology because they do not satisfy the axioms of a topological space: The empty set is not a subspace (subspaces have to contain 0) and the union of subspaces is not a subspace in general.

You may want to read http://en.wikipedia.org/wiki/Topological_vector_space" which describes the topologies one usually considers on a vector space.

Somewhat related to your idea is the http://en.wikipedia.org/wiki/Zariski_topology" , where the closed sets are the zero sets of a system of polynomials (vector subspaces are a special case).
 
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can't we make a linear space a topological space by construction, since we know that every non empty set can be made a topological space. ofcourse a linear space can never be empty for it contain the zero vector. Please still consider my question above, because i am really working on it
 
There are many ways in which a vector space can be equiped with a topology, I was just saying that your particular choice of open sets would not work. Of course one can choose a topology where the subspaces are open sets, for example the topology of all subsets, but this is not a very interesting topology.
 

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