What does it mean for a function $f$ to be continuous almost every where with respect to the measure induced...












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In this case $g$ is monotone increasing on the finite interval $[a,b]$. Does this mean that $f$ is continuous in the normal sense of continuity (ie. $|f(x)-f(y)| < epsilon$ when $|x-y|<delta$) except on a set of measure $0$ where the measure here is the measure induced by $g$?



For clarification here is he whole question I am asked to answer.




Let $g$ be a monotone function on a finite closed interval $[a,b]$. Show that a bounded function $f$ defined on $[a,b]$ is Riemann-Stieltjes integrable with respect to $g$ iff $f$ is continuous almost everywhere with respect to the measure induced by $g$.




Im guessing the measure induced by $g$ is the Borel measure, $mu_g$, with the property $mu_g(a,b) = g(b)-g(a)$ since $g$ is monotone.










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$endgroup$












  • $begingroup$
    "the measure induced by $g$": you mean $g(x)dx$ or $dg(x)$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:24










  • $begingroup$
    Riemann-Stieltjes measure induced by $g$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:25












  • $begingroup$
    @Federico what is the Riemann-Stiltjies measure induced by $g$?
    $endgroup$
    – mathworker21
    Dec 7 '18 at 18:25










  • $begingroup$
    What is the measure induced by $g$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:26










  • $begingroup$
    In any case, the answer would be yes; regardless of what measure you are considering
    $endgroup$
    – Federico
    Dec 7 '18 at 18:26
















0












$begingroup$


In this case $g$ is monotone increasing on the finite interval $[a,b]$. Does this mean that $f$ is continuous in the normal sense of continuity (ie. $|f(x)-f(y)| < epsilon$ when $|x-y|<delta$) except on a set of measure $0$ where the measure here is the measure induced by $g$?



For clarification here is he whole question I am asked to answer.




Let $g$ be a monotone function on a finite closed interval $[a,b]$. Show that a bounded function $f$ defined on $[a,b]$ is Riemann-Stieltjes integrable with respect to $g$ iff $f$ is continuous almost everywhere with respect to the measure induced by $g$.




Im guessing the measure induced by $g$ is the Borel measure, $mu_g$, with the property $mu_g(a,b) = g(b)-g(a)$ since $g$ is monotone.










share|cite|improve this question











$endgroup$












  • $begingroup$
    "the measure induced by $g$": you mean $g(x)dx$ or $dg(x)$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:24










  • $begingroup$
    Riemann-Stieltjes measure induced by $g$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:25












  • $begingroup$
    @Federico what is the Riemann-Stiltjies measure induced by $g$?
    $endgroup$
    – mathworker21
    Dec 7 '18 at 18:25










  • $begingroup$
    What is the measure induced by $g$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:26










  • $begingroup$
    In any case, the answer would be yes; regardless of what measure you are considering
    $endgroup$
    – Federico
    Dec 7 '18 at 18:26














0












0








0





$begingroup$


In this case $g$ is monotone increasing on the finite interval $[a,b]$. Does this mean that $f$ is continuous in the normal sense of continuity (ie. $|f(x)-f(y)| < epsilon$ when $|x-y|<delta$) except on a set of measure $0$ where the measure here is the measure induced by $g$?



For clarification here is he whole question I am asked to answer.




Let $g$ be a monotone function on a finite closed interval $[a,b]$. Show that a bounded function $f$ defined on $[a,b]$ is Riemann-Stieltjes integrable with respect to $g$ iff $f$ is continuous almost everywhere with respect to the measure induced by $g$.




Im guessing the measure induced by $g$ is the Borel measure, $mu_g$, with the property $mu_g(a,b) = g(b)-g(a)$ since $g$ is monotone.










share|cite|improve this question











$endgroup$




In this case $g$ is monotone increasing on the finite interval $[a,b]$. Does this mean that $f$ is continuous in the normal sense of continuity (ie. $|f(x)-f(y)| < epsilon$ when $|x-y|<delta$) except on a set of measure $0$ where the measure here is the measure induced by $g$?



For clarification here is he whole question I am asked to answer.




Let $g$ be a monotone function on a finite closed interval $[a,b]$. Show that a bounded function $f$ defined on $[a,b]$ is Riemann-Stieltjes integrable with respect to $g$ iff $f$ is continuous almost everywhere with respect to the measure induced by $g$.




Im guessing the measure induced by $g$ is the Borel measure, $mu_g$, with the property $mu_g(a,b) = g(b)-g(a)$ since $g$ is monotone.







measure-theory continuity






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share|cite|improve this question













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edited Dec 7 '18 at 18:29







alpast

















asked Dec 7 '18 at 18:22









alpastalpast

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468314












  • $begingroup$
    "the measure induced by $g$": you mean $g(x)dx$ or $dg(x)$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:24










  • $begingroup$
    Riemann-Stieltjes measure induced by $g$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:25












  • $begingroup$
    @Federico what is the Riemann-Stiltjies measure induced by $g$?
    $endgroup$
    – mathworker21
    Dec 7 '18 at 18:25










  • $begingroup$
    What is the measure induced by $g$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:26










  • $begingroup$
    In any case, the answer would be yes; regardless of what measure you are considering
    $endgroup$
    – Federico
    Dec 7 '18 at 18:26


















  • $begingroup$
    "the measure induced by $g$": you mean $g(x)dx$ or $dg(x)$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:24










  • $begingroup$
    Riemann-Stieltjes measure induced by $g$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:25












  • $begingroup$
    @Federico what is the Riemann-Stiltjies measure induced by $g$?
    $endgroup$
    – mathworker21
    Dec 7 '18 at 18:25










  • $begingroup$
    What is the measure induced by $g$?
    $endgroup$
    – Federico
    Dec 7 '18 at 18:26










  • $begingroup$
    In any case, the answer would be yes; regardless of what measure you are considering
    $endgroup$
    – Federico
    Dec 7 '18 at 18:26
















$begingroup$
"the measure induced by $g$": you mean $g(x)dx$ or $dg(x)$?
$endgroup$
– Federico
Dec 7 '18 at 18:24




$begingroup$
"the measure induced by $g$": you mean $g(x)dx$ or $dg(x)$?
$endgroup$
– Federico
Dec 7 '18 at 18:24












$begingroup$
Riemann-Stieltjes measure induced by $g$?
$endgroup$
– Federico
Dec 7 '18 at 18:25






$begingroup$
Riemann-Stieltjes measure induced by $g$?
$endgroup$
– Federico
Dec 7 '18 at 18:25














$begingroup$
@Federico what is the Riemann-Stiltjies measure induced by $g$?
$endgroup$
– mathworker21
Dec 7 '18 at 18:25




$begingroup$
@Federico what is the Riemann-Stiltjies measure induced by $g$?
$endgroup$
– mathworker21
Dec 7 '18 at 18:25












$begingroup$
What is the measure induced by $g$?
$endgroup$
– Federico
Dec 7 '18 at 18:26




$begingroup$
What is the measure induced by $g$?
$endgroup$
– Federico
Dec 7 '18 at 18:26












$begingroup$
In any case, the answer would be yes; regardless of what measure you are considering
$endgroup$
– Federico
Dec 7 '18 at 18:26




$begingroup$
In any case, the answer would be yes; regardless of what measure you are considering
$endgroup$
– Federico
Dec 7 '18 at 18:26










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