Superconnection and family Bergman kernels

Bergman Kernels and algebraic structure of limit space for a sequence of almost Kähler-Ricci solitons

In this paper, we give a lower bound of Bergman kernels for a sequence of almost Kähler-Einstein Fano manifolds, or more general, a sequence of Fano manifolds with almost Kähler-Ricci solitons. This generalizes a result by Donaldson-Sun, Tian for Kähler-Einstein manifolds sequence with positive scalar curvature. As an application of our result, we prove that the Gromov-Hausdorff limit of sequence is homomorphic to a log terminal $Q$-Fano variety which admits a Kähler-Ricci soliton on its smooth part.

Estimations of the Bergman kernel of the punctured disk

Using the techniques developed in \cite{SunSun}, we give estimations of the Bergman kernel of the punctured disk with the standard complete Poincaré metric. As an application, we improve the result of \cite{AMM} on the Bergman kernels of punctured Riemann surfaces near singularities.

Variation of the Bergman kernels under deformations of complex structures

Inspired by Berndtsson's work on the subharmonicity property of the Bergman kernel, we give a local variation formula of the full Bergman kernels associated to deformations of complex manifolds. In compact case, it follows from the reproducing property of the Bergman kernel and the curvature formula of the 0-th direct image sheaf. In general, following Schumacher's idea, we use the Lie derivative to compute the variation. An equivalent criterion for the triviality of holomorphic motions of planar domains in terms of the Bergman kernel is given as an application.

On the asymptotic expansion of Bergman kernel

We study the asymptotic of the Bergman kernel of the spin$^c$ Dirac operator on high tensor powers of a line bundle.

A comparison principle for Bergman kernels

We give a version of the comparison principle from pluripotential theory where the Monge-Ampère measure is replaced by the Bergman kernel and use it to derive a maximum principle

Off-diagonal estimates of the Bergman kernel on hyperbolic Riemann surfaces of finite volume

In this article, we derive off-diagonal estimates of the Bergman kernel associated to tensor- products of the cotangent line bundle defined over a hyperbolic Riemann surface of finite volume.

极化Kähler流形上的Bergman核、Bergman对数平坦性以及Lu-Tian的一个问题

Bergman kernels over polarized Kähler manifolds, Bergman logarithmic flatness, and a question of Lu-Tian

本文研究极化Kähler流形上两类Bergman核，建立无对数奇点的充要条件，回答Lu-Tian问题，并证明紧致局部齐性情形下圆丛的Bergman对数平坦性。

关于复双曲流形的Bergman核

On the Bergman Kernel of complex hyperbolic manifolds

本文推导了极化复双曲流形的Bergman核公式，将其表示为流形中的测地环路求和，并研究了Bergman核函数的最大最小值及离对角线Bergman核的估计。

A remark on weighted Bergman kernels on orbifolds

In this note, we explain that Ross-Thomas' result on the weighted Bergman kernels on orbifolds can be directly deduced from our previous result. This result plays an important role in the companion paper to prove an orbifold version of Donaldson Theorem.

Stability of the Bergman kernel on a tower of coverings

We obtain several results about stability of the Bergman kernel on a tower of coverings on complex manifolds. An effective version of Rhodes' result is given for a tower of coverings on a compact Riemann surface of genus greater than or equal to 2. Stability of the Bergman kernel is established for towers of coverings on hyperbolic Riemann surfaces and on complete Kaehler manifolds satisfying certain potential conditions. As a consequence, stability of the Bergman kernel is established for any tower of coverings of Riemann surfaces when the top manifold is simply-connected.

On the first order asymptotics of partial Bergman kernels

We show that under very general assumptions the partial Bergman kernel function of sections vanishing along an analytic hypersurface has exponential decay in a neighborhood of the vanishing locus. Considering an ample line bundle, we obtain a uniform estimate of the Bergman kernel function associated to a singular metric along the hypersurface. Finally, we study the asymptotics of the partial Bergman kernel function on a given compact set and near the vanishing locus.

Estimates of the Bergman kernel on Teichmuller space

In this paper, a comparison between the Bergman kernel form and the pushforward measure of the Masur-Veech meaure on the Teichmuller space of genus $g\ge 2$ is obtained.

The first coefficients of the asymptotic expansion of the Bergman kernel of the spin^c Dirac operator

We establish the existence of the asymptotic expansion of the Bergman kernel associated to the spin-c Dirac operators acting on high tensor powers of line bundles with non-degenerate mixed curvature (negative and positive eigenvalues) by extending the paper " On the asymptotic expansion of Bergman kernel " (math.DG/0404494) of Dai-Liu-Ma. We compute the second coefficient b_1 in the asymptotic expansion using the method of our paper "Generalized Bergman kernels on symplectic manifolds" (math.DG/0411559).

拟射影流形上Cheng-Yau度量的Bergman核

Bergman Kernels of the Cheng-Yau metrics on quasi-projective manifolds

该研究探讨拟射影流形上Cheng-Yau度量的Bergman核在无穷远光滑除子附近的渐近性，发现近除子点存在量子现象，丰富了复几何与度量几何的相关理论。

Covering stability of Bergman kernels on Kähler hyperbolic manifolds

This paper is a sequel to \cite{Xu}. In this paper, an estimation of the Bergman Kernel of Kähler hyperbolic manifold is given by the $L^2$ estimate and the Bochner formula. As an application, an effective criterion of the very ampleness of the canonical line bundle of Kähler hyperbolic manifold is given, which is a generalization of Yeung's result.

关于Bergman核函数与弱Morse不等式

On Bergman kernel functions and weak Morse inequalities

该研究利用渐近Bergman核函数与Bochner-Kodaira-Nakano公式，给出了多种流形及拟凸域上弱全纯Morse不等式的简单统一证明。

极化阿贝尔簇的Bergman核

On the Bergman kernel of polarized abelian varieties

本文研究极化阿贝尔簇的Bergman核，推导出显式公式，并探讨了正线 bundle 的同构性与Bergman核函数的极值点性质。

Remark on the off-diagonal expansion of the Bergman kernel on compact Kähler manifolds

In this short note, we compare our previous works on the off-diagonal expansion of the Bergman kernel and the recent preprint of Lu-Shiffman (arxiv.1301.2166). In particular, we note that the vanishing of the coefficient of p^{-1/2} is implicitly contained in Dai-Liu-Ma's work (J. Differential Geom. 72 (2006), no. 1, 1-41) and was explicitly stated in our book (Holomorphic Morse inequalities and Bergman kernels, Progress in Math., vol. 254, Birkhäuser, 2007).

(0,q)-形式的Bergman与谱核的半经典渐近

Semi-Classical Asymptotics of Bergman and Spectral Kernels for (0,q)-forms

本文提出一种新的缩放方法，在局部谱间隙条件下研究复流形上线丛张量幂的谱核与Bergman核，建立了点态渐近的简单证明，并获得了函数情形下指数衰减的Bergman核首项，且该渐近在曲率退化时仍有效。

Exponential Estimate for the asymptotics of Bergman kernels

We prove an exponential estimate for the asymptotics of Bergman kernels of a positive line bundle under hypotheses of bounded geometry. We give further Bergman kernel proofs of complex geometry results, such as separation of points, existence of local coordinates and holomorphic convexity by sections of positive line bundles.

退化情形下的 Bergman 核

Bergman kernels on degenerations

本文研究极化簇平坦退化中的 Bergman 核，定义逐纤维 Bergman 核并证明其连续性及 Fubini–Study 流的一致收敛性。

Algebraic Bergman kernels and finite type domains in $\mathbb{C}^2$

Let $G \subset \mathbb{C}^2$ be a smoothly bounded pseudoconvex domain and assume that the Bergman kernel of $G$ is algebraic of degree $d$. We show that the boundary $\partial G $ is of finite type and the type $r$ satisfies $r\leq 2d$. The inequality is optimal as equality holds for the egg domains $\{|z|^2+|w|^{2s}<1\},$ $s \in \mathbb{Z}_+$, by D'Angelo's explicit formula for their Bergman kernels. Our results imply, in particular, that a smoothly bounded pseudoconvex domain $G \subset \mathbb{C}^2$ cannot have rational Bergman kernel unless it is strongly pseudoconvex and biholomorphic to…

Limit of Bergman kernels on a tower of coverings of compact Kähler manifolds

We prove the convergence of the Bergman kernels and the $L^2$-Hodge numbers on a tower of Galois coverings $\{X_j\}$ of a compact Kähler manifold $X$ converging to an infinite Galois (not necessarily universal) covering $\widetilde{X}$. We also show that, as an application, sections of canonical line bundle $K_{X_j}$ for sufficiently large $j$ give rise to an immersion into some projective space, if so do sections of $K_{\widetilde{X}}$.

Bergman kernel and period map for curves

As for any symmetric space the tangent space to Siegel upper-half space is endowed with an operation coming from the Lie bracket on the Lie algebra. We consider the pull-back of this operation to the moduli space of curves via the Torelli map. We characterize it in terms of the geometry of the curve, using the Bergman kernel form associated to the curve. It is known that the second fundamental form of the Torelli map outside the hyperelliptic locus can be seen as the multiplication by a certain meromorphic form. Our second result says that the Bergman kernel form is the harmonic representative…

穿孔黎曼曲面上的半正线丛：Bergman核与随机零点

Semipositive line bundles on punctured Riemann surfaces: Bergman kernels and random zeros

本文研究了穿孔黎曼曲面上半正线丛的高张量幂的Bergman核展开及随机零点，证明了半经典极限下高斯全纯截面零点的等分布、大偏差、中心极限定理和数方差等结果。

Quotient of Bergman kernels on punctured Riemann surfaces

In this paper we consider a punctured Riemann surface endowed with a Hermitian metric that equals the Poincar{é} metric near the punctures, and a holomorphic line bundle that polarizes the metric. We show that the quotient of the Bergman kernel of high tensor powers of the line bundle and of the Bergman kernel of the Poincar{é} model near the singularity tends to one up to arbitrary negative powers of the tensor power.

Asymptotic expansion of the Bergman kernel via perturbation of the Bargmann-Fock model

We give an alternate proof of the existence of the asymptotic expansion of the Bergman kernel associated to the $k$-th tensor powers of a positive line bundle $L$ in a $\frac{1}{\sqrt{k}}$-neighborhood of the diagonal using elementary methods. We use the observation that after rescaling the Kähler potential $kφ$ in a $\frac{1}{\sqrt{k}}$-neighborhood of a given point, the potential becomes an asymptotic perturbation of the Bargmann-Fock metric. We then prove that the Bergman kernel is also an asymptotic perturbation of the Bargmann-Fock Bergman kernel.

Canonical measures and the dynamical systems of Bergman kernels

In this article, we construct the canonical semipositive current or the canonical measure ($=$ the potential of the canonical semipositive current) on a smooth projective variety of nonnegative Kodaira dimension in terms of a dynamical system of Bergman kernels. This current is considered to be a generalization of a Kähler-Einstein metric and coincides the one constructed independently by J. Song and G. Tian. The major difference between their work and the present article is that they found the canonical measure in terms of Käher-Ricci flows, while I found the canonical measure in terms of the…

Bergman核与Poincaré级数

Bergman kernels and Poincaré series

该研究通过证明Bergman核与群作用的关系，扩展了相对Poincaré级数不消失的结论，适用于一般有限体积的局部对称空间。

Bergman kernels on punctured Riemann surfaces

In this paper we consider a punctured Riemann surface endowed with a Hermitian metric which equals the Poincaré metric near the punctures and a holomorphic line bundle which polarizes the metric. We show that the Bergman kernel can be localized around the singularities and its local model is the Bergman kernel of the punctured unit disc endowed with the standard Poincaré metric. As a consequence, we obtain an optimal uniform estimate of the supremum norm of the Bergman kernel, involving a fractional growth order of the tensor power.

An explicit estimate of the Bergman kernel for positive line bundles

We shall give an explicit estimate of the lower bound of the Bergman kernel associated to a positive line bundle. In the compact Riemann surface case, our result can be seen as an explicit version of Tian's partial $C^0$-estimate.

Asymptotic of Bergman Kernel (Master Thesis)

In this master thesis, we give a new proof on the pointwise asymptotic expansion for Bergman kernel of a hermitian holomorphic line bundle on the points where the curvature of the line bundle is positive and satisfy local spectral gap condition. The main point is to introduce a suitable semi-classical symbol space and related symbolic calculus inspired from recent work of Hsiao and Savale. Particularly, we establish the existence of pointwise asymptotic expansion on the positive part for certain semi-positive line bundles.

Boundary asymptotics of the relative Bergman kernel metric for curves

We study the behaviors of the relative Bergman kernel metrics on holomorphic families of degenerating hyperelliptic Riemann surfaces and their Jacobian varieties. Near a node or cusp, we obtain precise asymptotic formulas with explicit coefficients. In general the Bergman kernels on a given cuspidal family do not always converge to that on the regular part of the limiting surface, which is different from the nodal case. It turns out that information on both the singularity and complex structure contributes to various asymptotic behaviors of the Bergman kernel. Our method involves the classical…

The second coefficient of the asymptotic expansion of the weighted Bergman kernel for $(0,q)$ forms on $\Complex^n$

Let $ϕ\in C^\infty(\Complex^n)$ be a given real valued function. We assume that $\pr\ddbarϕ$ is non-degenerate of constant signature $(n_-,n_+)$ on $\Complex^n$. When $q=n_-$, it is well-known that the Bergman kernel for $(0,q)$ forms with respect to the $k$-th weight $e^{-2kϕ}$, $k>0$, admits a full asymptotic expansion in $k$. In this paper, we compute the trace of the second coefficient of the asymptotic expansion on the diagonal.

Quantitative upper bounds for Bergman kernels associated to smooth Kähler potentials

We give upper bounds for the Bergman kernels associated to tensor powers of a smooth positive line bundle in terms of the rate of growth of the Taylor coefficients of the Kähler potential. As applications, we obtain improved off-diagonal rate of decay for the classes of analytic, quasi-analytic, and more generally Gevrey potentials.

具有复双曲尖点的Kähler流形上的峰截面与Bergman核

Peak sections and Bergman kernels on Kähler manifolds with complex hyperbolic cusps

本文重新审视Tian的峰截面方法，在具有复双曲尖点的Kähler流形上获得了Bergman核的局部化原理，推广了Auvray-Ma-Marinescu的结果，并在Kähler-Einstein度量与复球商情形下给出进一步估计，应用于Poincaré型尖点得到部分局部化结果。

Bergman kernels and symplectic reduction

We generalize several recent results concerning the asymptotic expansions of Bergman kernels to the framework of geometric quantization and establish an asymptotic symplectic identification property. More precisely, we study the asymptotic expansion of the $G$-invariant Bergman kernel of the spin^c Dirac operator associated with high tensor powers of a positive line bundle on a symplectic manifold. We also develop a way to compute the coefficients of the expansion, and compute the first few of them, especially, we obtain the scalar curvature of the reduction space from the $G$-invariant Bergma…

On a property of Bergman kernels when the Kähler potential is analytic

We provide a simple proof of a result of Rouby-Sjöstrand-Ngoc \cite{RSN} and Deleporte \cite{Deleporte}, which asserts that if the Kähler potential is real analytic then the Bergman kernel is an \textit{analytic kernel} meaning that its amplitude is an \textit{analytic symbol} and its phase is given by the polarization of the Kähler potential. This in particular shows that in the analytic case the Bergman kernel accepts an asymptotic expansion in a fixed neighborhood of the diagonal with an exponentially small remainder. The proof we provide is based on a linear recursive formula of L. Charles…

A closed formula for the asymptotic expansion of the Bergman kernel

We prove a graph theoretic closed formula for coefficients in the Tian-Yau-Zelditch asymptotic expansion of the Bergman kernel. The formula is expressed in terms of the characteristic polynomial of the directed graphs representing Weyl invariants. The proof relies on a combinatorial interpretation of a recursive formula due to M. Englis and A. Loi.

The asymptotic behaviour of Bergman kernels

Let $( X ,d ,p ) $ be the pointed Gromov-Hausdorff limit of a sequence of pointed complete polarized Kähler manifolds $( M_l ,ω_l ,\mathcal{L}_l ,h_l ,p_l ) $ with $Ric ( h_l ) =2πω_l $, $Ric ( ω_l ) \geq -Λω_l $ and $Vol \big( B_1 ( p_l ) \big) \geq v $, $\forall l\in\mathbb{N} $, where $Λ,v>0$ are constants. Then $X$ is a normal complex space [Liu-Székelyhidi, 2022, GAFA]. In this paper, we discuss the convergence of the Hermitian line bundles $( \mathcal{L}_l ,h_l )$ and the Bergman kernels. In particular, we show that the Kähler forms $ω_l $ converge to a unique closed positive current $ω_…

Integral Kahler Invariants and the Bergman kernel asymptotics for line bundles

On a compact Kahler manifold, one can define global invariants by integrating local invariants of the metric. Assume that a global invariant thus obtained depends only on the Kahler class. Then we show that the integrand can be decomposed into a Chern polynomial (the integrand of a Chern number) and divergences of one forms, which do not contribute to the integral. We apply this decomposition formula to describe the asymptotic expansion of the Bergman kernel for positive line bundles and to show that the CR Q-curvature on a Sasakian manifold is a divergence.

Bergman kernel on Riemann surfaces and Kaehler metric on symmetric products

Let $X$ be a compact hyperbolic Riemann surface equipped with the Poincaré metric. For any integer $k\geq 2$, we investigate the Bergman kernel associated to the holomorphic Hermitian line bundle $Ω^{\otimes k}_X$, where $Ø$ is the holomorphic cotangent bundle of $X$. Our first main result estimates the corresponding Bergman metric on $X$ in terms of the Poincaré metric. We then consider a certain natural embedding of the symmetric product of $X$ into a Grassmannian parametrizing subspaces of fixed dimension of the space of all global holomorphic sections of $Ω^{\otimes k}_X$. The Fubini-Study…

域上不变加权Bergman度量

Invariant weighted Bergman metrics on domains

本文引入不变权重指派概念，研究加权Bergman度量在双全纯映射下的不变性，并利用Bergman最小积分方法与Tian-Yau-Zelditch展开的域版本，证明了Tian和Tsuji核序列在一致挤压域上的一致收敛。

Bergman kernels and local holomorphic Morse inequalities

Let X be a hermitian manifold and let L^k be a high power of a hermitian line bundle over X. Local versions of Demailly's holomorphic Morse inequalities are presented - after integration they yield the usual inequalities. The local weak inequalities hold on any hermitian manifold X, regardless of compactness and completeness. The proofs, which are elementary, are based on a new approach to pointwise Bergman kernel estimates, where the kernels are estimated by a model kernel in the standard complex space C^n.

Asymptotic expansion of the off-diagonal Bergman kernel on compact Kähler manifolds

We compute the first four coefficients of the asymptotic off-diagonal expansion of the Bergman kernel for the N-th power of a positive line bundle on a compact Kaehler manifold, and we show that the coefficient b_1 of the N^{-1/2} term vanishes when we use a K-frame. We also show that all the coefficients of the expansion are polynomials in the K-coordinates and the covariant derivatives of the curvature and are homogeneous with respect to the weight w.

Bergman-Szegő kernel asymptotics in weakly pseudoconvex finite type cases

We construct a pointwise Boutet de Monvel-Sjöstrand parametrix for the Szegő kernel of a weakly pseudoconvex three dimensional CR manifold of finite type assuming the range of its tangential CR operator to be closed; thereby extending the earlier analysis of Christ. This particularly extends Fefferman's boundary asymptotics of the Bergman kernel to weakly pseudoconvex domains in $\mathbb{C}^{2}$, in agreement with D'Angelo's example. Finally our results generalize a three dimensional CR embedding theorem of Lempert.

Toeplitz算子、次乘法滤过与加权Bergman核

Toeplitz operators, submultiplicative filtrations and weighted Bergman kernels

本文证明极化复射影流形上次乘法滤过的权重算子是Toeplitz算子，并细化加权Bergman核的渐近分析，改进跳跃测度收敛结果。

黎曼曲面上半正线丛的Bochner拉普拉斯算子与Bergman核展开

Bochner Laplacian and Bergman kernel expansion of semi-positive line bundles on a Riemann surface

本研究推广了Montgomery关于线丛高张量幂上Bochner拉普拉斯算子的结果，特化到黎曼曲面时得到半正线丛的Bergman核展开与几何量子化结果，证明借助了Bochner拉普拉斯算子与次黎曼拉普拉斯算子的关联。

Asymptotic properties of Bergman kernels for potentials with Gevrey regularity

We study the asymptotic properties of the Bergman kernels associated to tensor powers of a positive line bundle on a compact Kähler manifold. We show that if the Kähler potential is in Gevrey class $G^a$ for some $a>1$, then the Bergman kernel accepts a complete asymptotic expansion in a neighborhood of the diagonal of shrinking size $k^{-\frac12+\frac{1}{4a+4\varepsilon}}$ for every $\varepsilon>0$. These improve the earlier results in the subject for smooth potentials, where an expansion exists in a $(\frac{\log k}{k})^{\frac12}$ neighborhood of the diagonal. We obtain our results by finding…

Bergman kernels and equidistribution for sequences of line bundles on Kähler manifolds

Given a sequence of positive Hermitian holomorphic line bundles $(L_p,h_p)$ on a Kähler manifold $X$, we establish the asymptotic expansion of the Bergman kernel of the space of global holomorphic sections of $L_p$, under a natural convergence assumption on the sequence of curvatures $c_1(L_p,h_p)$. We then apply this to study the asymptotic distribution of common zeros of random sequences of $m$-tuples of sections of $L_p$ as $p\to\infty$.

On asymptotic expansions of generalized Bergman kernels on symplectic manifolds

A full off-diagonal asymptotic expansion is established for the generalized Bergman kernels of the renormalized Bochner Laplacians associated with high tensor powers of a positive line bundle over a compact symplectic manifold. As an application, the algebra of Toeplitz operators on the symplectic manifold associated with the renormalized Bochner Laplacian is constructed.

Off-diagonal asymptotic properties of Bergman kernels associated to analytic Kähler potentials

We prove a new off-diagonal asymptotic of the Bergman kernels associated to tensor powers of a positive line bundle on a compact Kähler manifold. We show that if the Kähler potential is real analytic, then the Bergman kernel accepts a complete asymptotic expansion in a neighborhood of the diagonal of shrinking size $k^{-\frac14}$. These improve the earlier results in the subject for smooth potentials, where an expansion exists in a $k^{-\frac12}$ neighborhood of the diagonal. We obtain our results by finding upper bounds of the form $C^m m!^{2}$ for the Bergman coefficients $b_m(x, \bar y)$, w…

偏Bergman核与Kähler流形上的行列点过程

Partial Bergman kernels and determinantal point processes on Kähler manifolds

研究通过计算Kähler流形上的偏Bergman核渐进行为，揭示了行列点过程在点数趋于无穷时收敛于中心正态分布的性质。