Lebesgue Measure equal to any translation invariant Measure on the Borel sigma Algebra











up vote
0
down vote

favorite












I have come across a question in my measure theory textbook and can pretty much figure out how to construct an answer to the second part but not the first part. Any solutions or hints would be welcomed. The question is as follows:



Suppose $mu$ is a measure on $(mathbb{R}, B(mathbb{R}))$ such that $mu((0,1])=1$ and $mu$ is translation invariant. Here let $lambda$ denote the Lebesgue measure.



(i) Show that for every interval $A = (a,b]$ with $b-ainmathbb{Q}$, we have $mu(A)=lambda(A)$.



(ii) show that $mu=lambda$



Like I said I think I can do the second part by showing the the sets in part one which the measure agree on are a $pi$ system and then using the fact the Borel sets are generated by those intervals we can deduce the measure agree on the whole space, but I do not understand how to show they agree on the sets A in part (i).
Thanks in advance!










share|cite|improve this question






















  • See this.
    – Math enthusiast
    Nov 18 at 13:02










  • I don’t see how this relates as this Questions only deals with the Lebesgue Stieltjes Measure whereas my question is for a general one
    – Dani_5040
    Nov 19 at 10:38















up vote
0
down vote

favorite












I have come across a question in my measure theory textbook and can pretty much figure out how to construct an answer to the second part but not the first part. Any solutions or hints would be welcomed. The question is as follows:



Suppose $mu$ is a measure on $(mathbb{R}, B(mathbb{R}))$ such that $mu((0,1])=1$ and $mu$ is translation invariant. Here let $lambda$ denote the Lebesgue measure.



(i) Show that for every interval $A = (a,b]$ with $b-ainmathbb{Q}$, we have $mu(A)=lambda(A)$.



(ii) show that $mu=lambda$



Like I said I think I can do the second part by showing the the sets in part one which the measure agree on are a $pi$ system and then using the fact the Borel sets are generated by those intervals we can deduce the measure agree on the whole space, but I do not understand how to show they agree on the sets A in part (i).
Thanks in advance!










share|cite|improve this question






















  • See this.
    – Math enthusiast
    Nov 18 at 13:02










  • I don’t see how this relates as this Questions only deals with the Lebesgue Stieltjes Measure whereas my question is for a general one
    – Dani_5040
    Nov 19 at 10:38













up vote
0
down vote

favorite









up vote
0
down vote

favorite











I have come across a question in my measure theory textbook and can pretty much figure out how to construct an answer to the second part but not the first part. Any solutions or hints would be welcomed. The question is as follows:



Suppose $mu$ is a measure on $(mathbb{R}, B(mathbb{R}))$ such that $mu((0,1])=1$ and $mu$ is translation invariant. Here let $lambda$ denote the Lebesgue measure.



(i) Show that for every interval $A = (a,b]$ with $b-ainmathbb{Q}$, we have $mu(A)=lambda(A)$.



(ii) show that $mu=lambda$



Like I said I think I can do the second part by showing the the sets in part one which the measure agree on are a $pi$ system and then using the fact the Borel sets are generated by those intervals we can deduce the measure agree on the whole space, but I do not understand how to show they agree on the sets A in part (i).
Thanks in advance!










share|cite|improve this question













I have come across a question in my measure theory textbook and can pretty much figure out how to construct an answer to the second part but not the first part. Any solutions or hints would be welcomed. The question is as follows:



Suppose $mu$ is a measure on $(mathbb{R}, B(mathbb{R}))$ such that $mu((0,1])=1$ and $mu$ is translation invariant. Here let $lambda$ denote the Lebesgue measure.



(i) Show that for every interval $A = (a,b]$ with $b-ainmathbb{Q}$, we have $mu(A)=lambda(A)$.



(ii) show that $mu=lambda$



Like I said I think I can do the second part by showing the the sets in part one which the measure agree on are a $pi$ system and then using the fact the Borel sets are generated by those intervals we can deduce the measure agree on the whole space, but I do not understand how to show they agree on the sets A in part (i).
Thanks in advance!







measure-theory lebesgue-measure borel-sets borel-measures






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Nov 18 at 12:56









Dani_5040

373




373












  • See this.
    – Math enthusiast
    Nov 18 at 13:02










  • I don’t see how this relates as this Questions only deals with the Lebesgue Stieltjes Measure whereas my question is for a general one
    – Dani_5040
    Nov 19 at 10:38


















  • See this.
    – Math enthusiast
    Nov 18 at 13:02










  • I don’t see how this relates as this Questions only deals with the Lebesgue Stieltjes Measure whereas my question is for a general one
    – Dani_5040
    Nov 19 at 10:38
















See this.
– Math enthusiast
Nov 18 at 13:02




See this.
– Math enthusiast
Nov 18 at 13:02












I don’t see how this relates as this Questions only deals with the Lebesgue Stieltjes Measure whereas my question is for a general one
– Dani_5040
Nov 19 at 10:38




I don’t see how this relates as this Questions only deals with the Lebesgue Stieltjes Measure whereas my question is for a general one
– Dani_5040
Nov 19 at 10:38















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%2f3003495%2flebesgue-measure-equal-to-any-translation-invariant-measure-on-the-borel-sigma-a%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




















































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%2f3003495%2flebesgue-measure-equal-to-any-translation-invariant-measure-on-the-borel-sigma-a%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

QoS: MAC-Priority for clients behind a repeater

Ивакино (Тотемский район)

Can't locate Autom4te/ChannelDefs.pm in @INC (when it definitely is there)