Existance of $phi in L^2$ such as $L(vec v)=int_Omegaphi ;textdiv vec v ;dx$ The 2019 Stack Overflow Developer Survey Results Are Indual of $H^1_0$: $H^-1$ or $H_0^1$?Dual space of a closed subspace of a Hilbert spaceExample of an $H^-1$ function that isn't $L^2$Variational formulation curl-div equationHow can we extend $operatornamediv:C_c^infty(Omega)^dto L^p(Omega)$ to $W_0^1,:p(Omega)^d$?Definition of the Laplacian as an operator from $H_0^1(Omega)$ to $H_0^1(Omega)'$About the dual space of $V=uin H_0^1(Omega): textdivu=0 $ and its relations to $H^-1(Omega)$.Relation of $lVert dot u rVert_W^1(Omega)$ to $ lVert u rVert_W^1(Omega)$Continuous extension of an operator $textPI : H^s(partialOmega)to H^s+1/2(Omega)$Divergence operator: is it a linear continuous map on Sobolev Spaces?

Are there incongruent pythagorean triangles with the same perimeter and same area?

Can one be advised by a professor who is very far away?

Aging parents with no investments

Lightning Grid - Columns and Rows?

When should I buy a clipper card after flying to OAK?

Can you compress metal and what would be the consequences?

Time travel alters history but people keep saying nothing's changed

Can we generate random numbers using irrational numbers like π and e?

Is an up-to-date browser secure on an out-of-date OS?

How come people say “Would of”?

Is flight data recorder erased after every flight?

Am I thawing this London Broil safely?

For what reasons would an animal species NOT cross a *horizontal* land bridge?

Have you ever entered Singapore using a different passport or name?

How technical should a Scrum Master be to effectively remove impediments?

Why can Shazam fly?

If a Druid sees an animal’s corpse, can they wild shape into that animal?

If I score a critical hit on an 18 or higher, what are my chances of getting a critical hit if I roll 3d20?

What is the meaning of the verb "bear" in this context?

Multiply Two Integer Polynomials

How can I autofill dates in Excel excluding Sunday?

How to notate time signature switching consistently every measure

One word riddle: Vowel in the middle

What to do when moving next to a bird sanctuary with a loosely-domesticated cat?



Existance of $phi in L^2$ such as $L(vec v)=int_Omegaphi ;textdiv vec v ;dx$



The 2019 Stack Overflow Developer Survey Results Are Indual of $H^1_0$: $H^-1$ or $H_0^1$?Dual space of a closed subspace of a Hilbert spaceExample of an $H^-1$ function that isn't $L^2$Variational formulation curl-div equationHow can we extend $operatornamediv:C_c^infty(Omega)^dto L^p(Omega)$ to $W_0^1,:p(Omega)^d$?Definition of the Laplacian as an operator from $H_0^1(Omega)$ to $H_0^1(Omega)'$About the dual space of $V=uin H_0^1(Omega): textdivu=0 $ and its relations to $H^-1(Omega)$.Relation of $lVert dot u rVert_W^1(Omega)$ to $ lVert u rVert_W^1(Omega)$Continuous extension of an operator $textPI : H^s(partialOmega)to H^s+1/2(Omega)$Divergence operator: is it a linear continuous map on Sobolev Spaces?










0












$begingroup$


[I was working on Stokes pde, and I'm stuck in proving this, couldn't find it anywhere]



Let $Omega in mathbbR^N$ an open bounded connected set such as $partial Omega$ is $mathcalC^1$.



And we define $$V=vec v in (H^1_0(Omega))^N; textdiv vec v=0$$
With $textdiv vec v=sum_n=1^Nfracpartial v_ipartial x_i$.



I'm stuck in proving : if $L$ is a linear continious form on $(H_0^1(Omega))^N$ such as $L_V=0$ then there exists a function $phi in L^2(Omega)$, such as $$forall vec vin (H_0^1(Omega))^N : L(vec v)=int_Omegaphi ;textdiv vec v ;dx$$



My idea : I proved that $V$ is a closed space of $(H_0^1(Omega))^N$ then its a Hilbert space, and I tried to apply Riesz 's theorem, but ut doesn't work.










share|cite|improve this question











$endgroup$











  • $begingroup$
    $L$ is a function of $textdiv v$ since it maps those $v$ with the same div to the same value. Now the space of all $textdiv v$ is a subspace $Esubset L^2$, and $L$ is linear and bounded on $E$, so by Hahn-Banach then by Riesz there is $phiin L^2$ so that for all $uin E$ we have $L(u)=int phi u$, note $u=textdiv v$.
    $endgroup$
    – Yu Ding
    Mar 23 at 22:34











  • $begingroup$
    I get the idea, but I m not convinced, because saying that $L $ is a function of $div vec v $ (to me) does not make sense, because we suppose at beginning that $L$ is defined on $(H_0^1(Omega))^N$(note that this is a product space), and $div vec v$ is not a vector!
    $endgroup$
    – Anas
    Mar 24 at 7:42











  • $begingroup$
    Actually I mean there is $F$ so that $L(v)=F(textdiv v)$, and $F$ is linear, bounded on $L^2$, etc. as argued above......
    $endgroup$
    – Yu Ding
    Mar 24 at 8:07






  • 1




    $begingroup$
    Are you aware that you are asking about the de Rham lemma? You can find it in most literature on the mathematical theory of the (Navier-)Stokes equations, e.g. this book.
    $endgroup$
    – Fritz
    Mar 24 at 8:19










  • $begingroup$
    I Didn't know, I will check the book, thank you
    $endgroup$
    – Anas
    Mar 24 at 10:54















0












$begingroup$


[I was working on Stokes pde, and I'm stuck in proving this, couldn't find it anywhere]



Let $Omega in mathbbR^N$ an open bounded connected set such as $partial Omega$ is $mathcalC^1$.



And we define $$V=vec v in (H^1_0(Omega))^N; textdiv vec v=0$$
With $textdiv vec v=sum_n=1^Nfracpartial v_ipartial x_i$.



I'm stuck in proving : if $L$ is a linear continious form on $(H_0^1(Omega))^N$ such as $L_V=0$ then there exists a function $phi in L^2(Omega)$, such as $$forall vec vin (H_0^1(Omega))^N : L(vec v)=int_Omegaphi ;textdiv vec v ;dx$$



My idea : I proved that $V$ is a closed space of $(H_0^1(Omega))^N$ then its a Hilbert space, and I tried to apply Riesz 's theorem, but ut doesn't work.










share|cite|improve this question











$endgroup$











  • $begingroup$
    $L$ is a function of $textdiv v$ since it maps those $v$ with the same div to the same value. Now the space of all $textdiv v$ is a subspace $Esubset L^2$, and $L$ is linear and bounded on $E$, so by Hahn-Banach then by Riesz there is $phiin L^2$ so that for all $uin E$ we have $L(u)=int phi u$, note $u=textdiv v$.
    $endgroup$
    – Yu Ding
    Mar 23 at 22:34











  • $begingroup$
    I get the idea, but I m not convinced, because saying that $L $ is a function of $div vec v $ (to me) does not make sense, because we suppose at beginning that $L$ is defined on $(H_0^1(Omega))^N$(note that this is a product space), and $div vec v$ is not a vector!
    $endgroup$
    – Anas
    Mar 24 at 7:42











  • $begingroup$
    Actually I mean there is $F$ so that $L(v)=F(textdiv v)$, and $F$ is linear, bounded on $L^2$, etc. as argued above......
    $endgroup$
    – Yu Ding
    Mar 24 at 8:07






  • 1




    $begingroup$
    Are you aware that you are asking about the de Rham lemma? You can find it in most literature on the mathematical theory of the (Navier-)Stokes equations, e.g. this book.
    $endgroup$
    – Fritz
    Mar 24 at 8:19










  • $begingroup$
    I Didn't know, I will check the book, thank you
    $endgroup$
    – Anas
    Mar 24 at 10:54













0












0








0





$begingroup$


[I was working on Stokes pde, and I'm stuck in proving this, couldn't find it anywhere]



Let $Omega in mathbbR^N$ an open bounded connected set such as $partial Omega$ is $mathcalC^1$.



And we define $$V=vec v in (H^1_0(Omega))^N; textdiv vec v=0$$
With $textdiv vec v=sum_n=1^Nfracpartial v_ipartial x_i$.



I'm stuck in proving : if $L$ is a linear continious form on $(H_0^1(Omega))^N$ such as $L_V=0$ then there exists a function $phi in L^2(Omega)$, such as $$forall vec vin (H_0^1(Omega))^N : L(vec v)=int_Omegaphi ;textdiv vec v ;dx$$



My idea : I proved that $V$ is a closed space of $(H_0^1(Omega))^N$ then its a Hilbert space, and I tried to apply Riesz 's theorem, but ut doesn't work.










share|cite|improve this question











$endgroup$




[I was working on Stokes pde, and I'm stuck in proving this, couldn't find it anywhere]



Let $Omega in mathbbR^N$ an open bounded connected set such as $partial Omega$ is $mathcalC^1$.



And we define $$V=vec v in (H^1_0(Omega))^N; textdiv vec v=0$$
With $textdiv vec v=sum_n=1^Nfracpartial v_ipartial x_i$.



I'm stuck in proving : if $L$ is a linear continious form on $(H_0^1(Omega))^N$ such as $L_V=0$ then there exists a function $phi in L^2(Omega)$, such as $$forall vec vin (H_0^1(Omega))^N : L(vec v)=int_Omegaphi ;textdiv vec v ;dx$$



My idea : I proved that $V$ is a closed space of $(H_0^1(Omega))^N$ then its a Hilbert space, and I tried to apply Riesz 's theorem, but ut doesn't work.







pde sobolev-spaces stokes-theorem






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Mar 23 at 17:30







Anas

















asked Mar 23 at 17:22









AnasAnas

395




395











  • $begingroup$
    $L$ is a function of $textdiv v$ since it maps those $v$ with the same div to the same value. Now the space of all $textdiv v$ is a subspace $Esubset L^2$, and $L$ is linear and bounded on $E$, so by Hahn-Banach then by Riesz there is $phiin L^2$ so that for all $uin E$ we have $L(u)=int phi u$, note $u=textdiv v$.
    $endgroup$
    – Yu Ding
    Mar 23 at 22:34











  • $begingroup$
    I get the idea, but I m not convinced, because saying that $L $ is a function of $div vec v $ (to me) does not make sense, because we suppose at beginning that $L$ is defined on $(H_0^1(Omega))^N$(note that this is a product space), and $div vec v$ is not a vector!
    $endgroup$
    – Anas
    Mar 24 at 7:42











  • $begingroup$
    Actually I mean there is $F$ so that $L(v)=F(textdiv v)$, and $F$ is linear, bounded on $L^2$, etc. as argued above......
    $endgroup$
    – Yu Ding
    Mar 24 at 8:07






  • 1




    $begingroup$
    Are you aware that you are asking about the de Rham lemma? You can find it in most literature on the mathematical theory of the (Navier-)Stokes equations, e.g. this book.
    $endgroup$
    – Fritz
    Mar 24 at 8:19










  • $begingroup$
    I Didn't know, I will check the book, thank you
    $endgroup$
    – Anas
    Mar 24 at 10:54
















  • $begingroup$
    $L$ is a function of $textdiv v$ since it maps those $v$ with the same div to the same value. Now the space of all $textdiv v$ is a subspace $Esubset L^2$, and $L$ is linear and bounded on $E$, so by Hahn-Banach then by Riesz there is $phiin L^2$ so that for all $uin E$ we have $L(u)=int phi u$, note $u=textdiv v$.
    $endgroup$
    – Yu Ding
    Mar 23 at 22:34











  • $begingroup$
    I get the idea, but I m not convinced, because saying that $L $ is a function of $div vec v $ (to me) does not make sense, because we suppose at beginning that $L$ is defined on $(H_0^1(Omega))^N$(note that this is a product space), and $div vec v$ is not a vector!
    $endgroup$
    – Anas
    Mar 24 at 7:42











  • $begingroup$
    Actually I mean there is $F$ so that $L(v)=F(textdiv v)$, and $F$ is linear, bounded on $L^2$, etc. as argued above......
    $endgroup$
    – Yu Ding
    Mar 24 at 8:07






  • 1




    $begingroup$
    Are you aware that you are asking about the de Rham lemma? You can find it in most literature on the mathematical theory of the (Navier-)Stokes equations, e.g. this book.
    $endgroup$
    – Fritz
    Mar 24 at 8:19










  • $begingroup$
    I Didn't know, I will check the book, thank you
    $endgroup$
    – Anas
    Mar 24 at 10:54















$begingroup$
$L$ is a function of $textdiv v$ since it maps those $v$ with the same div to the same value. Now the space of all $textdiv v$ is a subspace $Esubset L^2$, and $L$ is linear and bounded on $E$, so by Hahn-Banach then by Riesz there is $phiin L^2$ so that for all $uin E$ we have $L(u)=int phi u$, note $u=textdiv v$.
$endgroup$
– Yu Ding
Mar 23 at 22:34





$begingroup$
$L$ is a function of $textdiv v$ since it maps those $v$ with the same div to the same value. Now the space of all $textdiv v$ is a subspace $Esubset L^2$, and $L$ is linear and bounded on $E$, so by Hahn-Banach then by Riesz there is $phiin L^2$ so that for all $uin E$ we have $L(u)=int phi u$, note $u=textdiv v$.
$endgroup$
– Yu Ding
Mar 23 at 22:34













$begingroup$
I get the idea, but I m not convinced, because saying that $L $ is a function of $div vec v $ (to me) does not make sense, because we suppose at beginning that $L$ is defined on $(H_0^1(Omega))^N$(note that this is a product space), and $div vec v$ is not a vector!
$endgroup$
– Anas
Mar 24 at 7:42





$begingroup$
I get the idea, but I m not convinced, because saying that $L $ is a function of $div vec v $ (to me) does not make sense, because we suppose at beginning that $L$ is defined on $(H_0^1(Omega))^N$(note that this is a product space), and $div vec v$ is not a vector!
$endgroup$
– Anas
Mar 24 at 7:42













$begingroup$
Actually I mean there is $F$ so that $L(v)=F(textdiv v)$, and $F$ is linear, bounded on $L^2$, etc. as argued above......
$endgroup$
– Yu Ding
Mar 24 at 8:07




$begingroup$
Actually I mean there is $F$ so that $L(v)=F(textdiv v)$, and $F$ is linear, bounded on $L^2$, etc. as argued above......
$endgroup$
– Yu Ding
Mar 24 at 8:07




1




1




$begingroup$
Are you aware that you are asking about the de Rham lemma? You can find it in most literature on the mathematical theory of the (Navier-)Stokes equations, e.g. this book.
$endgroup$
– Fritz
Mar 24 at 8:19




$begingroup$
Are you aware that you are asking about the de Rham lemma? You can find it in most literature on the mathematical theory of the (Navier-)Stokes equations, e.g. this book.
$endgroup$
– Fritz
Mar 24 at 8:19












$begingroup$
I Didn't know, I will check the book, thank you
$endgroup$
– Anas
Mar 24 at 10:54




$begingroup$
I Didn't know, I will check the book, thank you
$endgroup$
– Anas
Mar 24 at 10:54










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%2f3159598%2fexistance-of-phi-in-l2-such-as-l-vec-v-int-omega-phi-textdiv-v%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.




draft saved


draft discarded














StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3159598%2fexistance-of-phi-in-l2-such-as-l-vec-v-int-omega-phi-textdiv-v%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

Lowndes Grove History Architecture References Navigation menu32°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661132°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661178002500"National Register Information System"Historic houses of South Carolina"Lowndes Grove""+32° 48' 6.00", −79° 57' 58.00""Lowndes Grove, Charleston County (260 St. Margaret St., Charleston)""Lowndes Grove"The Charleston ExpositionIt Happened in South Carolina"Lowndes Grove (House), Saint Margaret Street & Sixth Avenue, Charleston, Charleston County, SC(Photographs)"Plantations of the Carolina Low Countrye

random experiment with two different functions on unit interval Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern)Random variable and probability space notionsRandom Walk with EdgesFinding functions where the increase over a random interval is Poisson distributedNumber of days until dayCan an observed event in fact be of zero probability?Unit random processmodels of coins and uniform distributionHow to get the number of successes given $n$ trials , probability $P$ and a random variable $X$Absorbing Markov chain in a computer. Is “almost every” turned into always convergence in computer executions?Stopped random walk is not uniformly integrable

How should I support this large drywall patch? Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern) Announcing the arrival of Valued Associate #679: Cesar Manara Unicorn Meta Zoo #1: Why another podcast?How do I cover large gaps in drywall?How do I keep drywall around a patch from crumbling?Can I glue a second layer of drywall?How to patch long strip on drywall?Large drywall patch: how to avoid bulging seams?Drywall Mesh Patch vs. Bulge? To remove or not to remove?How to fix this drywall job?Prep drywall before backsplashWhat's the best way to fix this horrible drywall patch job?Drywall patching using 3M Patch Plus Primer