Local property of a flat family of schemes












1












$begingroup$


Let $pi: X to S$ be a flat, smooth family of genus $0$ curves, for example. Now take a point $x in S$, then $x in pi{-1}(p)$ from some $p in S$, i.e $x in mathbb{P}^1$.



I am trying to relate such families to first order infinitesimal deformations.



In particular, does there exist an open subset $ xin U subset X$ such that $U$ is a first order infinitesimal deformation of $mathbb{P}^1$?










share|cite|improve this question









$endgroup$












  • $begingroup$
    In your first paragraph, $x in S$ and (presumably) $x in pi^{-1}(p)$, which doesn't make sense.
    $endgroup$
    – RghtHndSd
    Dec 12 '18 at 3:31


















1












$begingroup$


Let $pi: X to S$ be a flat, smooth family of genus $0$ curves, for example. Now take a point $x in S$, then $x in pi{-1}(p)$ from some $p in S$, i.e $x in mathbb{P}^1$.



I am trying to relate such families to first order infinitesimal deformations.



In particular, does there exist an open subset $ xin U subset X$ such that $U$ is a first order infinitesimal deformation of $mathbb{P}^1$?










share|cite|improve this question









$endgroup$












  • $begingroup$
    In your first paragraph, $x in S$ and (presumably) $x in pi^{-1}(p)$, which doesn't make sense.
    $endgroup$
    – RghtHndSd
    Dec 12 '18 at 3:31
















1












1








1





$begingroup$


Let $pi: X to S$ be a flat, smooth family of genus $0$ curves, for example. Now take a point $x in S$, then $x in pi{-1}(p)$ from some $p in S$, i.e $x in mathbb{P}^1$.



I am trying to relate such families to first order infinitesimal deformations.



In particular, does there exist an open subset $ xin U subset X$ such that $U$ is a first order infinitesimal deformation of $mathbb{P}^1$?










share|cite|improve this question









$endgroup$




Let $pi: X to S$ be a flat, smooth family of genus $0$ curves, for example. Now take a point $x in S$, then $x in pi{-1}(p)$ from some $p in S$, i.e $x in mathbb{P}^1$.



I am trying to relate such families to first order infinitesimal deformations.



In particular, does there exist an open subset $ xin U subset X$ such that $U$ is a first order infinitesimal deformation of $mathbb{P}^1$?







algebraic-geometry commutative-algebra deformation-theory






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Dec 4 '18 at 20:01









JadwigaJadwiga

2,02311024




2,02311024












  • $begingroup$
    In your first paragraph, $x in S$ and (presumably) $x in pi^{-1}(p)$, which doesn't make sense.
    $endgroup$
    – RghtHndSd
    Dec 12 '18 at 3:31




















  • $begingroup$
    In your first paragraph, $x in S$ and (presumably) $x in pi^{-1}(p)$, which doesn't make sense.
    $endgroup$
    – RghtHndSd
    Dec 12 '18 at 3:31


















$begingroup$
In your first paragraph, $x in S$ and (presumably) $x in pi^{-1}(p)$, which doesn't make sense.
$endgroup$
– RghtHndSd
Dec 12 '18 at 3:31






$begingroup$
In your first paragraph, $x in S$ and (presumably) $x in pi^{-1}(p)$, which doesn't make sense.
$endgroup$
– RghtHndSd
Dec 12 '18 at 3:31












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%2f3026081%2flocal-property-of-a-flat-family-of-schemes%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%2f3026081%2flocal-property-of-a-flat-family-of-schemes%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

Bundesstraße 106

Verónica Boquete

Ida-Boy-Ed-Garten