Minimal or Maximal Von Neumann algebra contained in a given $C^*$ algebra











up vote
1
down vote

favorite
1












Let $A,B subset B(H)$ be two concrete von Neumann algebra. Is $Acap B$ a von Neumann algebra, too?



What about the intrinsic analogy of this question, as follows:



Let $C$ be a $C^*$ algebra and $A,B subset C$ be two von Neumann algebras. Is their intersection, a von Neumann algebra, too?



Can one speak of a kind of minimal von Neumann algebra contained in a given $C^*$ algebra?



On the other extreme, can one think of a kind of maximal von Neumann algebra contained in a given $C^*$ algebra?



In particular what are two maximal von neumann algebras in $B(H)$ which are not isomorphic?










share|cite|improve this question




















  • 1




    For the first question the answer is yes, because intersection behaves nicely in both algebra and topology. For the rest, I prefer $C^*$-algebras over von-Neumann algebras, so wait for an expert to reply.
    – Aweygan
    10 hours ago















up vote
1
down vote

favorite
1












Let $A,B subset B(H)$ be two concrete von Neumann algebra. Is $Acap B$ a von Neumann algebra, too?



What about the intrinsic analogy of this question, as follows:



Let $C$ be a $C^*$ algebra and $A,B subset C$ be two von Neumann algebras. Is their intersection, a von Neumann algebra, too?



Can one speak of a kind of minimal von Neumann algebra contained in a given $C^*$ algebra?



On the other extreme, can one think of a kind of maximal von Neumann algebra contained in a given $C^*$ algebra?



In particular what are two maximal von neumann algebras in $B(H)$ which are not isomorphic?










share|cite|improve this question




















  • 1




    For the first question the answer is yes, because intersection behaves nicely in both algebra and topology. For the rest, I prefer $C^*$-algebras over von-Neumann algebras, so wait for an expert to reply.
    – Aweygan
    10 hours ago













up vote
1
down vote

favorite
1









up vote
1
down vote

favorite
1






1





Let $A,B subset B(H)$ be two concrete von Neumann algebra. Is $Acap B$ a von Neumann algebra, too?



What about the intrinsic analogy of this question, as follows:



Let $C$ be a $C^*$ algebra and $A,B subset C$ be two von Neumann algebras. Is their intersection, a von Neumann algebra, too?



Can one speak of a kind of minimal von Neumann algebra contained in a given $C^*$ algebra?



On the other extreme, can one think of a kind of maximal von Neumann algebra contained in a given $C^*$ algebra?



In particular what are two maximal von neumann algebras in $B(H)$ which are not isomorphic?










share|cite|improve this question















Let $A,B subset B(H)$ be two concrete von Neumann algebra. Is $Acap B$ a von Neumann algebra, too?



What about the intrinsic analogy of this question, as follows:



Let $C$ be a $C^*$ algebra and $A,B subset C$ be two von Neumann algebras. Is their intersection, a von Neumann algebra, too?



Can one speak of a kind of minimal von Neumann algebra contained in a given $C^*$ algebra?



On the other extreme, can one think of a kind of maximal von Neumann algebra contained in a given $C^*$ algebra?



In particular what are two maximal von neumann algebras in $B(H)$ which are not isomorphic?







operator-theory operator-algebras c-star-algebras von-neumann-algebras






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited 4 hours ago

























asked 11 hours ago









Ali Taghavi

199329




199329








  • 1




    For the first question the answer is yes, because intersection behaves nicely in both algebra and topology. For the rest, I prefer $C^*$-algebras over von-Neumann algebras, so wait for an expert to reply.
    – Aweygan
    10 hours ago














  • 1




    For the first question the answer is yes, because intersection behaves nicely in both algebra and topology. For the rest, I prefer $C^*$-algebras over von-Neumann algebras, so wait for an expert to reply.
    – Aweygan
    10 hours ago








1




1




For the first question the answer is yes, because intersection behaves nicely in both algebra and topology. For the rest, I prefer $C^*$-algebras over von-Neumann algebras, so wait for an expert to reply.
– Aweygan
10 hours ago




For the first question the answer is yes, because intersection behaves nicely in both algebra and topology. For the rest, I prefer $C^*$-algebras over von-Neumann algebras, so wait for an expert to reply.
– Aweygan
10 hours ago















active

oldest

votes











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',
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%2f3000879%2fminimal-or-maximal-von-neumann-algebra-contained-in-a-given-c-algebra%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown






























active

oldest

votes













active

oldest

votes









active

oldest

votes






active

oldest

votes
















 

draft saved


draft discarded



















































 


draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3000879%2fminimal-or-maximal-von-neumann-algebra-contained-in-a-given-c-algebra%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

Le Mesnil-Réaume

Ida-Boy-Ed-Garten

web3.py web3.isConnected() returns false always