Mathematics

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Apr 20, 2022 19:29
Hello. Does anyone know where I can know about the hodge diamond of projective curves?
Apr 16, 2022 18:37
be right back I will be back later.
Apr 16, 2022 18:24
Excuse me. I want to ask, so $H$ is given by $V(h) \cap X$. Look at the homogeneous polynomial h, if we pick an affine chart and set one of projective coordinate equal to 1. If we convert back to Projective coordinates we get rational function $s$ on $X$ such that $div(s)_X = H + \text{other things}$?
Apr 16, 2022 18:18
yes
Apr 16, 2022 18:12
If X is a variety and $D$ is a divisor then for $m$ big enough we have $mH - D$ is very amply, so there exists effective divisor $D^{\prime}$ such that $mH - D \sim D^{\prime}$?
Apr 16, 2022 18:07
@TedShifrin Yeah, so we we get the above. Ty!
Apr 16, 2022 17:59
What does hyperplane section section of a variety X means? Does it mean it is given by a single equation? If $H$ is hyperplane section in $X$, does this mean that $H = V(h) \cap X$?
Apr 16, 2022 17:59
Hello
Feb 16, 2022 04:56
The reason I want this is because I want to construct some metric on Y
Feb 16, 2022 04:55
given a smooth family of maps $X \rightarrow (0,\infty)$ I want to construct a smooth family of maps $Y \rightarrow (0,\infty)$
Feb 16, 2022 04:54
I want to construct a smooth family on $Y$
Feb 16, 2022 04:51
@leslietownes 1 moment I will explain
Feb 16, 2022 04:49
so $p_{\alpha}$ is a smooth family on X
Feb 16, 2022 04:48
1 sec reading
Feb 16, 2022 04:48
@leslietownes wait what?
Feb 16, 2022 04:26
@leslietownes do you agree?
Feb 16, 2022 04:26
then we can define $p_{\alpha}^{\prime} : X \rightarrow (0,\infty)$ I think this is also a family of smooth maps, do you agree?
Feb 16, 2022 04:25
surjection will allow that given any element $y \in Y$ we have at least one $x_y$ that maps to $y$ we can use axiom of choice to make a consistent choice of $x_y$ that maps to $y$.
Feb 16, 2022 04:24
@leslietownes If I have a collection of $C^{\infty}$ families on $Y$ denoted as $p_{\alpha} : Y \rightarrow (0,\infty)$ then I want a collection of $C^{\infty}$ families on $X$.
Feb 16, 2022 04:22
@leslietownes I wrote it in the wrong direction
Feb 16, 2022 04:06
Suppose we have a surjective map $\phi : X \rightarrow Y$. Let us say we have collection of $C^{\infty}$ maps on $X$ denoted as ${ p_{\alpha} : X \rightarrow (0,\infty) }$. We can use axiom of choice to define a collection of $C^{\infty}$ maps on Y right? That is a collection ${ p^{\prime}_{\alpha} : Y \rightarrow (0,\infty) }$.
Feb 16, 2022 04:05
Hello