Submanifold of real projective space
$begingroup$
Would you like to tell me how to prove that ${[x_{0}:x_{1}:x_{2}]: x_{0}x_{1} + x_{2}^{2} = 0 } subset mathbb{R}mathbb{P}^{2}$ is a submanifold (of $mathbb{R}mathbb{P}^{2}$)?
differential-geometry differential-topology projective-space
$endgroup$
add a comment |
$begingroup$
Would you like to tell me how to prove that ${[x_{0}:x_{1}:x_{2}]: x_{0}x_{1} + x_{2}^{2} = 0 } subset mathbb{R}mathbb{P}^{2}$ is a submanifold (of $mathbb{R}mathbb{P}^{2}$)?
differential-geometry differential-topology projective-space
$endgroup$
add a comment |
$begingroup$
Would you like to tell me how to prove that ${[x_{0}:x_{1}:x_{2}]: x_{0}x_{1} + x_{2}^{2} = 0 } subset mathbb{R}mathbb{P}^{2}$ is a submanifold (of $mathbb{R}mathbb{P}^{2}$)?
differential-geometry differential-topology projective-space
$endgroup$
Would you like to tell me how to prove that ${[x_{0}:x_{1}:x_{2}]: x_{0}x_{1} + x_{2}^{2} = 0 } subset mathbb{R}mathbb{P}^{2}$ is a submanifold (of $mathbb{R}mathbb{P}^{2}$)?
differential-geometry differential-topology projective-space
differential-geometry differential-topology projective-space
edited Dec 13 '18 at 8:39
kNiEsSoKk
asked Dec 12 '18 at 14:09
kNiEsSoKkkNiEsSoKk
6710
6710
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
I believe you want to say $x_0x_1+x_2^2=0$. Let $V$ be that subset. Consider $U_0={[x_0,x_1,x_2],x_0neq 0}$ define $f([x_0,x_1,x_2])={x_1over x_0}+{x_2^2over x_0^2}$ is a submersion on $U_0$ this shows that $Vcap U_0$ is a submanifold.
$endgroup$
$begingroup$
Thanks! I found the proposition $f:mathbb{R}mathbb{P}^{2} rightarrow mathbb{R}$ smooth and $qinmathbb{R}$ a regular value $implies f^{-1}(q)$ is a submanifold of $mathbb{R}mathbb{P}^{2}$. Is this what you are using?
$endgroup$
– kNiEsSoKk
Dec 13 '18 at 9:56
add a comment |
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
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3036729%2fsubmanifold-of-real-projective-space%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
I believe you want to say $x_0x_1+x_2^2=0$. Let $V$ be that subset. Consider $U_0={[x_0,x_1,x_2],x_0neq 0}$ define $f([x_0,x_1,x_2])={x_1over x_0}+{x_2^2over x_0^2}$ is a submersion on $U_0$ this shows that $Vcap U_0$ is a submanifold.
$endgroup$
$begingroup$
Thanks! I found the proposition $f:mathbb{R}mathbb{P}^{2} rightarrow mathbb{R}$ smooth and $qinmathbb{R}$ a regular value $implies f^{-1}(q)$ is a submanifold of $mathbb{R}mathbb{P}^{2}$. Is this what you are using?
$endgroup$
– kNiEsSoKk
Dec 13 '18 at 9:56
add a comment |
$begingroup$
I believe you want to say $x_0x_1+x_2^2=0$. Let $V$ be that subset. Consider $U_0={[x_0,x_1,x_2],x_0neq 0}$ define $f([x_0,x_1,x_2])={x_1over x_0}+{x_2^2over x_0^2}$ is a submersion on $U_0$ this shows that $Vcap U_0$ is a submanifold.
$endgroup$
$begingroup$
Thanks! I found the proposition $f:mathbb{R}mathbb{P}^{2} rightarrow mathbb{R}$ smooth and $qinmathbb{R}$ a regular value $implies f^{-1}(q)$ is a submanifold of $mathbb{R}mathbb{P}^{2}$. Is this what you are using?
$endgroup$
– kNiEsSoKk
Dec 13 '18 at 9:56
add a comment |
$begingroup$
I believe you want to say $x_0x_1+x_2^2=0$. Let $V$ be that subset. Consider $U_0={[x_0,x_1,x_2],x_0neq 0}$ define $f([x_0,x_1,x_2])={x_1over x_0}+{x_2^2over x_0^2}$ is a submersion on $U_0$ this shows that $Vcap U_0$ is a submanifold.
$endgroup$
I believe you want to say $x_0x_1+x_2^2=0$. Let $V$ be that subset. Consider $U_0={[x_0,x_1,x_2],x_0neq 0}$ define $f([x_0,x_1,x_2])={x_1over x_0}+{x_2^2over x_0^2}$ is a submersion on $U_0$ this shows that $Vcap U_0$ is a submanifold.
answered Dec 12 '18 at 15:28
Tsemo AristideTsemo Aristide
58.7k11445
58.7k11445
$begingroup$
Thanks! I found the proposition $f:mathbb{R}mathbb{P}^{2} rightarrow mathbb{R}$ smooth and $qinmathbb{R}$ a regular value $implies f^{-1}(q)$ is a submanifold of $mathbb{R}mathbb{P}^{2}$. Is this what you are using?
$endgroup$
– kNiEsSoKk
Dec 13 '18 at 9:56
add a comment |
$begingroup$
Thanks! I found the proposition $f:mathbb{R}mathbb{P}^{2} rightarrow mathbb{R}$ smooth and $qinmathbb{R}$ a regular value $implies f^{-1}(q)$ is a submanifold of $mathbb{R}mathbb{P}^{2}$. Is this what you are using?
$endgroup$
– kNiEsSoKk
Dec 13 '18 at 9:56
$begingroup$
Thanks! I found the proposition $f:mathbb{R}mathbb{P}^{2} rightarrow mathbb{R}$ smooth and $qinmathbb{R}$ a regular value $implies f^{-1}(q)$ is a submanifold of $mathbb{R}mathbb{P}^{2}$. Is this what you are using?
$endgroup$
– kNiEsSoKk
Dec 13 '18 at 9:56
$begingroup$
Thanks! I found the proposition $f:mathbb{R}mathbb{P}^{2} rightarrow mathbb{R}$ smooth and $qinmathbb{R}$ a regular value $implies f^{-1}(q)$ is a submanifold of $mathbb{R}mathbb{P}^{2}$. Is this what you are using?
$endgroup$
– kNiEsSoKk
Dec 13 '18 at 9:56
add a comment |
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.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3036729%2fsubmanifold-of-real-projective-space%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
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