What's the definition of proper subspace of a vector space used in Rudin's Functional analysis












0














I'm reading through the Rudin's functional analysis, and theorem 3.5 use the term "Proper Subspace", there's a theorem in chapter 2 that uses the same terminology.



I'm reading through chapter 1 again, and through the glossary as well but I cannot find the definition used.



I guess there must be a standard definition then,



What is such definition?










share|cite|improve this question


















  • 2




    It a subspace different from the vector space.
    – Bernard
    Nov 30 at 10:29










  • So literally it's a proper subset that is also a vector space, correct?
    – user8469759
    Nov 30 at 10:30












  • Yes, absolutely.
    – Bernard
    Nov 30 at 10:33
















0














I'm reading through the Rudin's functional analysis, and theorem 3.5 use the term "Proper Subspace", there's a theorem in chapter 2 that uses the same terminology.



I'm reading through chapter 1 again, and through the glossary as well but I cannot find the definition used.



I guess there must be a standard definition then,



What is such definition?










share|cite|improve this question


















  • 2




    It a subspace different from the vector space.
    – Bernard
    Nov 30 at 10:29










  • So literally it's a proper subset that is also a vector space, correct?
    – user8469759
    Nov 30 at 10:30












  • Yes, absolutely.
    – Bernard
    Nov 30 at 10:33














0












0








0







I'm reading through the Rudin's functional analysis, and theorem 3.5 use the term "Proper Subspace", there's a theorem in chapter 2 that uses the same terminology.



I'm reading through chapter 1 again, and through the glossary as well but I cannot find the definition used.



I guess there must be a standard definition then,



What is such definition?










share|cite|improve this question













I'm reading through the Rudin's functional analysis, and theorem 3.5 use the term "Proper Subspace", there's a theorem in chapter 2 that uses the same terminology.



I'm reading through chapter 1 again, and through the glossary as well but I cannot find the definition used.



I guess there must be a standard definition then,



What is such definition?







functional-analysis vector-spaces definition topological-vector-spaces






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Nov 30 at 10:25









user8469759

1,3311616




1,3311616








  • 2




    It a subspace different from the vector space.
    – Bernard
    Nov 30 at 10:29










  • So literally it's a proper subset that is also a vector space, correct?
    – user8469759
    Nov 30 at 10:30












  • Yes, absolutely.
    – Bernard
    Nov 30 at 10:33














  • 2




    It a subspace different from the vector space.
    – Bernard
    Nov 30 at 10:29










  • So literally it's a proper subset that is also a vector space, correct?
    – user8469759
    Nov 30 at 10:30












  • Yes, absolutely.
    – Bernard
    Nov 30 at 10:33








2




2




It a subspace different from the vector space.
– Bernard
Nov 30 at 10:29




It a subspace different from the vector space.
– Bernard
Nov 30 at 10:29












So literally it's a proper subset that is also a vector space, correct?
– user8469759
Nov 30 at 10:30






So literally it's a proper subset that is also a vector space, correct?
– user8469759
Nov 30 at 10:30














Yes, absolutely.
– Bernard
Nov 30 at 10:33




Yes, absolutely.
– Bernard
Nov 30 at 10:33










1 Answer
1






active

oldest

votes


















2














$V$ is a proper subspace of $X$ if
$V$ is a subspace of $X$ and $Vsubsetneq X$.



I would guess that there is no definition of proper subspace in the book,
since a proper subspace is a subspace that is also a proper subset.






share|cite|improve this answer























  • Does this definition imply that the only proper subspace of $mathbb{R}$ is $left{ 0 right}$ and that proper subspaces of topological vector spaces have empty interiors?
    – user8469759
    Nov 30 at 10:35












  • @user8469759 yes
    – supinf
    Nov 30 at 10:35











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1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









2














$V$ is a proper subspace of $X$ if
$V$ is a subspace of $X$ and $Vsubsetneq X$.



I would guess that there is no definition of proper subspace in the book,
since a proper subspace is a subspace that is also a proper subset.






share|cite|improve this answer























  • Does this definition imply that the only proper subspace of $mathbb{R}$ is $left{ 0 right}$ and that proper subspaces of topological vector spaces have empty interiors?
    – user8469759
    Nov 30 at 10:35












  • @user8469759 yes
    – supinf
    Nov 30 at 10:35
















2














$V$ is a proper subspace of $X$ if
$V$ is a subspace of $X$ and $Vsubsetneq X$.



I would guess that there is no definition of proper subspace in the book,
since a proper subspace is a subspace that is also a proper subset.






share|cite|improve this answer























  • Does this definition imply that the only proper subspace of $mathbb{R}$ is $left{ 0 right}$ and that proper subspaces of topological vector spaces have empty interiors?
    – user8469759
    Nov 30 at 10:35












  • @user8469759 yes
    – supinf
    Nov 30 at 10:35














2












2








2






$V$ is a proper subspace of $X$ if
$V$ is a subspace of $X$ and $Vsubsetneq X$.



I would guess that there is no definition of proper subspace in the book,
since a proper subspace is a subspace that is also a proper subset.






share|cite|improve this answer














$V$ is a proper subspace of $X$ if
$V$ is a subspace of $X$ and $Vsubsetneq X$.



I would guess that there is no definition of proper subspace in the book,
since a proper subspace is a subspace that is also a proper subset.







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited Nov 30 at 10:34

























answered Nov 30 at 10:29









supinf

5,9491027




5,9491027












  • Does this definition imply that the only proper subspace of $mathbb{R}$ is $left{ 0 right}$ and that proper subspaces of topological vector spaces have empty interiors?
    – user8469759
    Nov 30 at 10:35












  • @user8469759 yes
    – supinf
    Nov 30 at 10:35


















  • Does this definition imply that the only proper subspace of $mathbb{R}$ is $left{ 0 right}$ and that proper subspaces of topological vector spaces have empty interiors?
    – user8469759
    Nov 30 at 10:35












  • @user8469759 yes
    – supinf
    Nov 30 at 10:35
















Does this definition imply that the only proper subspace of $mathbb{R}$ is $left{ 0 right}$ and that proper subspaces of topological vector spaces have empty interiors?
– user8469759
Nov 30 at 10:35






Does this definition imply that the only proper subspace of $mathbb{R}$ is $left{ 0 right}$ and that proper subspaces of topological vector spaces have empty interiors?
– user8469759
Nov 30 at 10:35














@user8469759 yes
– supinf
Nov 30 at 10:35




@user8469759 yes
– supinf
Nov 30 at 10:35


















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