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Mingshuo Zhou

Publications and source records attributed to Mingshuo Zhou.

12 recordsLinked to original sources

Moduli spaces and the algebra of conformal blocks

For a classical simple and simply connected group $G$, let $\mathcal{M}_{G,ω}$ be the moduli space of $ω$-semistable parabolic $G$-bundles on a complex smooth projective curve of genus $g$. We prove two results in this article: (1) $\mathcal{M}_{G,ω}$ is of Fano type when $g\geq 3$; (2) the algebra of conformal blocks on any $n$-pointed stable curve for a classical simple Lie algebra is finitely generated.

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Frobenius splitting of moduli spaces of parabolic bundles

Let $C$ be a nonsingular projective curve over an algebraically closed field of characteristic $p>0$ and $I\subset C$ be a finite set. If $\mathcal{U}_{C,\,ω}$ denotes the moduli space of semistable parabolic bundles of rank $r$ and degree $d$ on $C$ with parabolic structures determined by $ω=(k,\{\vec n(x),\vec a(x)\}_{x\in I})$, we prove that $\mathcal{U}_{C,\,ω}$ is \textit{$F$-split} for generic $C$ and generic choice of $I$ when $p>3r$.

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A finite dimensional proof of Verlinde Formula

We prove two recurrence relations among dimensions $$D_g(r,d,ω):={\rm dim}\,{\rm H}^0(\mathcal{U}_{C,\,ω},Θ_{\mathcal{U}_{C,\,ω}})$$ of spaces of generalized theta functions on moduli spaces $\mathcal{U}_{C,\,ω}$. By using of these recurrence relations, an explicit formula (Verlinde formula) of $D_g(r,d,ω)$ is proved (See Theorem 4.3).

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Globally F-regular type of Moduli spaces

We prove moduli spaces of semistable parabolic bundles and generalized parabolic sheaves with fixed determinant on a smooth projective curve are globally $F$-regular type.

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Slope inequalities and a Miyaoka-Yau type inequality

For a minimal smooth projective surface $S$ of general type over a field of characteristic $p>0$, we prove that $K^2_S\le 32χ(\cal{O}_S).$ Moreover, if $18χ(\cal{O}_S) 0$, which answers completely a question of Shepherd-Barron.

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Surfaces on the Severi line in positive characteristics

Let $X$ be a minimal surface of general type over an algebraically closed field $\mathbf{k}$ of $\mathrm{char}.(\mathbf{k})=p\ge 0$. If the Albanese morphism $a_X:X\to \mathrm{Alb}_X$ is generically finite onto its image, we formulate a constant $c(X,L)\ge 0$ for a very ample line bundle $L$ on $\mathrm{Alb}_X$ such that $c(X,L)=0$ if and only if $\dim \mathrm{Alb}_X=2$ and $a_X: X\to \mathrm{Alb}_X$ is a double cover. A refined Severi inequality $$K^2_X\ge (4+{\rm min}\{\,c(X,L),\,\frac{1}{3}\,\})χ(\mathcal{O}_X)$$ is proved. Then we prove that $K^2_X=4χ(\mathcal{O}_X)$ if and only if the canonical model of $X$ is a flat double cover of an Abelian surface.

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Globally F-regular type of moduli spaces and Verlinde formula

We prove that moduli spaces of semistable parabolic bundles and generalized parabolic sheaves (GPS) with a fixed determinant on a smooth projective curve are globally F-regular type. As an application, we prove vanishing theorems on the moduli spaces of semistable parabolic sheaves on a singular curve, which combining with Factorization theorems in [24] and [25] give two recurrence relations among dimensions of spaces of generalized theta functions. By using of these recurrence relations, we prove an explicit formula (Verlinde formula) for the dimension of spaces of generalized theta functions.

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Remarks on Xiao's approach of Slope inequalities

We prove the slope inequality for a relative minimal surface fibration in positive characteristic via Xiao's approach. We also prove a better low bound for the slope of non-hyperelliptic fibrations.

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Rational curves and lines on the moduli space of stable bundles

Fix a smooth projetive curve $\mathcal {C}$ of genus $g\geq 2$ and a line bundle $\mathcal{L}$ on $\mathcal{C}$ of degree $d$. Let $M:= \mathcal{SU}_{\mathcal{C}}(r, \mathcal{L})$ be the moduli space of stable vector bundles on $\mathcal{C}$ of rank $r$ and with fixed determinant $\mathcal{L}$. We prove that any rational curve on $M$ is a generalized Hecke curve. Furthermore, we study the lines on $M$, and prove that $M$ is covered by the lines when $(r, d)=r$; for the case $(r,d) (r,d)+1$. Finally, we prove that there are no $(1,0)$-stable (resp., $(0,1)$-stable) bundles for $g=2$, $r=2$ and $d$ is odd as an application.

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Stability of Frobenius direct images over surfaces

Let $X$ be a smooth projective surface over an algebraically closed field $k$ of characteristic $p> 0$ with $Ω_{X}^{1}$ semistable and $μ(Ω_{X}^{1})>0$. For any semistable (resp. stable) bundle $W$ of rank $r$, we prove that $F_*W$ is semistable (resp. stable) when $p\geq r(r-1)^2+1$.

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The H_N filtration of bundles as Frobenius pull-back

Let X be a smooth projective curve over an algebraic closed field of characteristic p and F be the Frobenius morphism of X. Here, I give a negative answer to the guess that the length of the Harder-Narasimhan of F*W is not bigger than p, where W is a semistable bundle on X.

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Stable bundles as Frobenius morphism direct image

Let X be a smooth projective curve of genus $g\geq 2$ defined over an algebraically closed field k of characteristic $p>0$ and let $F:X\rightarrow X_{1}$ be the relative k-linear Frobenius map. We prove (Theorem 1.1) E is a stable bundle on $X_{1}$ with $I(E)= (p-1)(2g-2)$ if and only if E is the direct image of some stable bundle W on $X$.

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