Search arXivSearch

arXiv · 1610.03297

Real submanifolds of maximum complex tangent space at a CR singular point, II

Abstract

We study a germ of real analytic n-dimensional submanifold of $C^n$ that has a complex tangent space of maximal dimension at a CR singularity. Under the condition that its complexification admits the maximum number of deck transformations, we first classify holomorphically its quadratic CR singularity. We then study its transformation to a normal form under the action of local (possibly formal) biholomorphisms at the singularity. We first conjugate formally its associated reversible map $σ$ to suitable normal forms and show that all these normal forms can be divergent. We then construct a unique formal normal form under a non degeneracy condition.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Xianghong Gong, Laurent Stolovitch. 2016-10-11. Real submanifolds of maximum complex tangent space at a CR singular point, II. https://arxiv.org/abs/1610.03297

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Convolution Regularization Preserves the $L^2$-Estimate Property for $(1,n)$-Forms

In this paper, we prove that the \(L^2\)-estimate property for \((1,n)\)-forms is preserved under the standard convolution regularization. As applications, we show that any singular Hermitian metric satisfying the optimal or multiple coarse \(L^2\)-estimate property for \((n,1)\) or \((1,n)\)-forms is Griffiths semi-positive. This resolves a question posed by Deng--Ning--Wang and a question by Inayama.

math.CV

Sharp Bounds for Higher-Order Schippers Functionals Associated with Lune and Bean Domains

We obtain sharp bounds for the third- and fourth-order Schippers functionals, $|σ_3(f)(0)|$ and $|σ_4(f)(0)|$, for subclasses of univalent functions associated with non-classical geometric domains. In particular, we investigate the lune-starlike class $\mathcal{S}_{\leftmoon}^*$ and the lune-convex class $\mathcal{C}_{\leftmoon}$ determined by the subordination \[ \frac{zf'(z)}{f(z)} \prec z+\sqrt{1+z^2}, \qquad 1+\frac{zf''(z)}{f'(z)} \prec z+\sqrt{1+z^2}, \] respectively, together with the bean-domain class $\mathcal{BT}_{\mathfrak{B}}$ associated with \[ \mathfrak{B}(z)=\sqrt{1+\tanh z}. \] Using Carathéodory coefficient parametrizations and extremal optimization techniques, we derive exact estimates for the higher-order Schwarzian derivatives at the origin and identify the corresponding extremal functions. In addition, geometric descriptions of the associated extremal image domains are provided to illustrate the sharpness phenomena. The obtained results further yield sharp bounds for the initial Grunsky coefficients $g_{1,1}$ and $g_{1,2}$. These findings provide a precise description of higher-order Schwarzian structures for univalent functions related to lune and bean shaped domains.

math.CV

Cesàro operator induced by a Bergman kernel

Let $μ$ be a positive Borel measure on $[0,1)$ and $ω$ a radial weight. In this paper we consider the Cesàro-type operator $C_{μ,ω}$ induced by the reproducing kernel $B^ω$ of the weighted Bergman space $A^2_ω$, given by $$ C_{μ,ω}(f)(z)=\int_{0}^{1}f(tz)B^ω_t(z)\,dμ(t), \quad z \in \mathbb{D}, $$ for functions $f$ analytic in $\mathbb{D}$. Under the assumption that $ω$ satisfies a natural doubling property, we study the boundedness of $C_{μ,ω}$ acting on several spaces of analytic functions, including Hardy spaces $H^p$ and weighted Bergman spaces $A^p_ν$. For $0<p,q<\infty$ and a two-sided doubling weight $ν$, we completely characterize when $C_{μ,ω}: H^p \to H^q$ and $C_{μ,ω}: A^p_ν \to A^q_ν$ are bounded in terms of the interplay of tail integrals or moments of the inducing weights and the measure $μ$. Many of the results obtained are new even in the setting of standard weights or when the Bergman reproducing kernel is replaced by the Cauchy kernel. In addition, we consider $C_{μ,ω}$ acting on $H^{\infty}$, Korenblum spaces and weighted Hardy spaces.

math.CV