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












0












$begingroup$


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









$endgroup$








  • 2




    $begingroup$
    It a subspace different from the vector space.
    $endgroup$
    – Bernard
    Nov 30 '18 at 10:29










  • $begingroup$
    So literally it's a proper subset that is also a vector space, correct?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:30












  • $begingroup$
    Yes, absolutely.
    $endgroup$
    – Bernard
    Nov 30 '18 at 10:33
















0












$begingroup$


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









$endgroup$








  • 2




    $begingroup$
    It a subspace different from the vector space.
    $endgroup$
    – Bernard
    Nov 30 '18 at 10:29










  • $begingroup$
    So literally it's a proper subset that is also a vector space, correct?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:30












  • $begingroup$
    Yes, absolutely.
    $endgroup$
    – Bernard
    Nov 30 '18 at 10:33














0












0








0





$begingroup$


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









$endgroup$




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 '18 at 10:25









user8469759user8469759

1,3851617




1,3851617








  • 2




    $begingroup$
    It a subspace different from the vector space.
    $endgroup$
    – Bernard
    Nov 30 '18 at 10:29










  • $begingroup$
    So literally it's a proper subset that is also a vector space, correct?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:30












  • $begingroup$
    Yes, absolutely.
    $endgroup$
    – Bernard
    Nov 30 '18 at 10:33














  • 2




    $begingroup$
    It a subspace different from the vector space.
    $endgroup$
    – Bernard
    Nov 30 '18 at 10:29










  • $begingroup$
    So literally it's a proper subset that is also a vector space, correct?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:30












  • $begingroup$
    Yes, absolutely.
    $endgroup$
    – Bernard
    Nov 30 '18 at 10:33








2




2




$begingroup$
It a subspace different from the vector space.
$endgroup$
– Bernard
Nov 30 '18 at 10:29




$begingroup$
It a subspace different from the vector space.
$endgroup$
– Bernard
Nov 30 '18 at 10:29












$begingroup$
So literally it's a proper subset that is also a vector space, correct?
$endgroup$
– user8469759
Nov 30 '18 at 10:30






$begingroup$
So literally it's a proper subset that is also a vector space, correct?
$endgroup$
– user8469759
Nov 30 '18 at 10:30














$begingroup$
Yes, absolutely.
$endgroup$
– Bernard
Nov 30 '18 at 10:33




$begingroup$
Yes, absolutely.
$endgroup$
– Bernard
Nov 30 '18 at 10:33










1 Answer
1






active

oldest

votes


















2












$begingroup$

$V$ 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











$endgroup$













  • $begingroup$
    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?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:35












  • $begingroup$
    @user8469759 yes
    $endgroup$
    – supinf
    Nov 30 '18 at 10:35











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3019932%2fwhats-the-definition-of-proper-subspace-of-a-vector-space-used-in-rudins-funct%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









2












$begingroup$

$V$ 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











$endgroup$













  • $begingroup$
    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?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:35












  • $begingroup$
    @user8469759 yes
    $endgroup$
    – supinf
    Nov 30 '18 at 10:35
















2












$begingroup$

$V$ 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











$endgroup$













  • $begingroup$
    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?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:35












  • $begingroup$
    @user8469759 yes
    $endgroup$
    – supinf
    Nov 30 '18 at 10:35














2












2








2





$begingroup$

$V$ 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











$endgroup$



$V$ 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 '18 at 10:34

























answered Nov 30 '18 at 10:29









supinfsupinf

6,1241028




6,1241028












  • $begingroup$
    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?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:35












  • $begingroup$
    @user8469759 yes
    $endgroup$
    – supinf
    Nov 30 '18 at 10:35


















  • $begingroup$
    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?
    $endgroup$
    – user8469759
    Nov 30 '18 at 10:35












  • $begingroup$
    @user8469759 yes
    $endgroup$
    – supinf
    Nov 30 '18 at 10:35
















$begingroup$
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?
$endgroup$
– user8469759
Nov 30 '18 at 10:35






$begingroup$
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?
$endgroup$
– user8469759
Nov 30 '18 at 10:35














$begingroup$
@user8469759 yes
$endgroup$
– supinf
Nov 30 '18 at 10:35




$begingroup$
@user8469759 yes
$endgroup$
– supinf
Nov 30 '18 at 10:35


















draft saved

draft discarded




















































Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3019932%2fwhats-the-definition-of-proper-subspace-of-a-vector-space-used-in-rudins-funct%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Bundesstraße 106

Verónica Boquete

Ida-Boy-Ed-Garten