Defining powerset of $Omega = [0, 1]$ in measure theory context












0














I am confused about the concept of powerset in the following context.



I am reading the Bandit Algorithm book (http://banditalgs.com/) by Csaba Szepesvari. There it gives the following theorem:



Theorem 2.1: Let $Omega = [0,1]$ and $mathcal{F}$ is the powerset of $Omega$. Then there does not exist a measure $mathbb{P}$ on $(Omega, mathcal{F})$ such that $mathbb{P}([a,b]) = b-a$ for all $0leq a leq b leq 1$.



What does the powerset of $Omega$ look like since there are infinitely many real numbers in it?










share|cite|improve this question




















  • 4




    That's an odd question. The power set is the collection of all subsets.
    – Asaf Karagila
    Dec 12 '18 at 16:18










  • It seems you're just asking about the powerset of the unit interval. I understand your concern since each element of the set $S$ is drawn from a continuum, so there are uncountably many elements in it, it's doubly difficult to imagine every possible subset of $S$. But this powerset contains every single isolated point, every segment, every union of those, and every possible combination of finitely many, countably many, or uncountably many of those.
    – user334732
    Dec 12 '18 at 18:28












  • It is hard to "visualize". A version of Cantor's diagonal argument shows that there are an infinity of subsets of $[0,1]$, with this infinity being much larger than the infinite number of real numbers in the set $[0,1]$.
    – hardmath
    Dec 12 '18 at 20:04
















0














I am confused about the concept of powerset in the following context.



I am reading the Bandit Algorithm book (http://banditalgs.com/) by Csaba Szepesvari. There it gives the following theorem:



Theorem 2.1: Let $Omega = [0,1]$ and $mathcal{F}$ is the powerset of $Omega$. Then there does not exist a measure $mathbb{P}$ on $(Omega, mathcal{F})$ such that $mathbb{P}([a,b]) = b-a$ for all $0leq a leq b leq 1$.



What does the powerset of $Omega$ look like since there are infinitely many real numbers in it?










share|cite|improve this question




















  • 4




    That's an odd question. The power set is the collection of all subsets.
    – Asaf Karagila
    Dec 12 '18 at 16:18










  • It seems you're just asking about the powerset of the unit interval. I understand your concern since each element of the set $S$ is drawn from a continuum, so there are uncountably many elements in it, it's doubly difficult to imagine every possible subset of $S$. But this powerset contains every single isolated point, every segment, every union of those, and every possible combination of finitely many, countably many, or uncountably many of those.
    – user334732
    Dec 12 '18 at 18:28












  • It is hard to "visualize". A version of Cantor's diagonal argument shows that there are an infinity of subsets of $[0,1]$, with this infinity being much larger than the infinite number of real numbers in the set $[0,1]$.
    – hardmath
    Dec 12 '18 at 20:04














0












0








0







I am confused about the concept of powerset in the following context.



I am reading the Bandit Algorithm book (http://banditalgs.com/) by Csaba Szepesvari. There it gives the following theorem:



Theorem 2.1: Let $Omega = [0,1]$ and $mathcal{F}$ is the powerset of $Omega$. Then there does not exist a measure $mathbb{P}$ on $(Omega, mathcal{F})$ such that $mathbb{P}([a,b]) = b-a$ for all $0leq a leq b leq 1$.



What does the powerset of $Omega$ look like since there are infinitely many real numbers in it?










share|cite|improve this question















I am confused about the concept of powerset in the following context.



I am reading the Bandit Algorithm book (http://banditalgs.com/) by Csaba Szepesvari. There it gives the following theorem:



Theorem 2.1: Let $Omega = [0,1]$ and $mathcal{F}$ is the powerset of $Omega$. Then there does not exist a measure $mathbb{P}$ on $(Omega, mathcal{F})$ such that $mathbb{P}([a,b]) = b-a$ for all $0leq a leq b leq 1$.



What does the powerset of $Omega$ look like since there are infinitely many real numbers in it?







probability-theory measure-theory terminology






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Dec 12 '18 at 16:28









Andrés E. Caicedo

64.9k8158246




64.9k8158246










asked Dec 12 '18 at 15:55









hi15hi15

1436




1436








  • 4




    That's an odd question. The power set is the collection of all subsets.
    – Asaf Karagila
    Dec 12 '18 at 16:18










  • It seems you're just asking about the powerset of the unit interval. I understand your concern since each element of the set $S$ is drawn from a continuum, so there are uncountably many elements in it, it's doubly difficult to imagine every possible subset of $S$. But this powerset contains every single isolated point, every segment, every union of those, and every possible combination of finitely many, countably many, or uncountably many of those.
    – user334732
    Dec 12 '18 at 18:28












  • It is hard to "visualize". A version of Cantor's diagonal argument shows that there are an infinity of subsets of $[0,1]$, with this infinity being much larger than the infinite number of real numbers in the set $[0,1]$.
    – hardmath
    Dec 12 '18 at 20:04














  • 4




    That's an odd question. The power set is the collection of all subsets.
    – Asaf Karagila
    Dec 12 '18 at 16:18










  • It seems you're just asking about the powerset of the unit interval. I understand your concern since each element of the set $S$ is drawn from a continuum, so there are uncountably many elements in it, it's doubly difficult to imagine every possible subset of $S$. But this powerset contains every single isolated point, every segment, every union of those, and every possible combination of finitely many, countably many, or uncountably many of those.
    – user334732
    Dec 12 '18 at 18:28












  • It is hard to "visualize". A version of Cantor's diagonal argument shows that there are an infinity of subsets of $[0,1]$, with this infinity being much larger than the infinite number of real numbers in the set $[0,1]$.
    – hardmath
    Dec 12 '18 at 20:04








4




4




That's an odd question. The power set is the collection of all subsets.
– Asaf Karagila
Dec 12 '18 at 16:18




That's an odd question. The power set is the collection of all subsets.
– Asaf Karagila
Dec 12 '18 at 16:18












It seems you're just asking about the powerset of the unit interval. I understand your concern since each element of the set $S$ is drawn from a continuum, so there are uncountably many elements in it, it's doubly difficult to imagine every possible subset of $S$. But this powerset contains every single isolated point, every segment, every union of those, and every possible combination of finitely many, countably many, or uncountably many of those.
– user334732
Dec 12 '18 at 18:28






It seems you're just asking about the powerset of the unit interval. I understand your concern since each element of the set $S$ is drawn from a continuum, so there are uncountably many elements in it, it's doubly difficult to imagine every possible subset of $S$. But this powerset contains every single isolated point, every segment, every union of those, and every possible combination of finitely many, countably many, or uncountably many of those.
– user334732
Dec 12 '18 at 18:28














It is hard to "visualize". A version of Cantor's diagonal argument shows that there are an infinity of subsets of $[0,1]$, with this infinity being much larger than the infinite number of real numbers in the set $[0,1]$.
– hardmath
Dec 12 '18 at 20:04




It is hard to "visualize". A version of Cantor's diagonal argument shows that there are an infinity of subsets of $[0,1]$, with this infinity being much larger than the infinite number of real numbers in the set $[0,1]$.
– hardmath
Dec 12 '18 at 20:04










0






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',
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%2f3036860%2fdefining-powerset-of-omega-0-1-in-measure-theory-context%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes
















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.





Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


Please pay close attention to the following guidance:


  • 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.


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%2f3036860%2fdefining-powerset-of-omega-0-1-in-measure-theory-context%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

Bressuire

Cabo Verde

Gyllenstierna