Berezin-Toeplitz quantization and the least unsharpness principle

A matrix-valued Berezin-Toeplitz quantization

We generalize some earlier results on a Berezin-Toeplitz type of quantization on Hilbert spaces built over certain matrix domains. In the present, wider setting, the theory could be applied to systems possessing several kinematic and internal degrees of freedom. Our analysis leads to an identification of those observables, in this general context, which admit a semi-classical limit and those for which no such limit exists. It turns out that the latter class of observables involve the internal degrees of freedom in an intrinsic way. Mathematically, the theory, being a generalization of the stan…

Semi-classical properties of Berezin--Toeplitz operators with $\cC^k$--\,symbol

We obtain the semi-classical expansion of the kernels and traces of Toeplitz operators with $\cC^k$--\,symbol on a symplectic manifold. We also give a semi-classical estimate of the distance of a Toeplitz operator to the space of self-adjoint and multiplication operators.

Berezin-Toeplitz quantization and its kernel expansion

We survey recent results about the asymptotic expansion of Toeplitz operators and their kernels, as well as Berezin-Toeplitz quantization. We deal in particular with calculation of the first coefficients of these expansions.

Berezin-Toeplitz quantization for compact Kaehler manifolds. A Review of Results

This article is a review on Berezin-Toeplitz operator and Berezin-Toeplitz deformation quantization for compact quantizable Kaehler manifolds. The basic objects, concepts, and results are given. This concerns the correct semi-classical limit behaviour of the operator quantization, the unique Berezin-Toeplitz deformation quantization (star product), covariant and contravariant Berezin symbols, and Berezin transform. Other related objects and constructions are also discussed.

Berezin-Toeplitz quantization on symplectic manifolds of bounded geometry

We establish the theory of Berezin-Toeplitz quantization on symplectic manifolds of bounded geometry. The quantum space of this quantization is the spectral subspace of the renormalized Bochner Laplacian associated with some interval near zero. We show that this quantization has the correct semiclassical limit.

Identification of Berezin-Toeplitz deformation quantization

We give a complete identification of the deformation quantization which was obtained from the Berezin-Toeplitz quantization on an arbitrary compact Kaehler manifold. The deformation quantization with the opposite star-product proves to be a differential deformation quantization with separation of variables whose classifying form is explicitly calculated. Its characteristic class (which classifies star-products up to equivalence) is obtained. The proof is based on the microlocal description of the Szegoe kernel of a strictly pseudoconvex domain given by Boutet de Monvel and Sjoestrand.

On a formula of Gammelgaard for Berezin-Toeplitz quantization

We give a proof of a slightly refined version of Gammelgaard's graph theoretic formula for Berezin-Toeplitz quantization on (pseudo-)Kaehler manifolds. Our proof has the merit of giving an alternative approach to Karabegov-Schlichenmaier's identification theorem. We also identify the dual Karabegov-Bordemann-Waldmann star product.

A transformation formula relating resolvents of Berezin-Toeplitz operators by an invariance property of Brownian motion

Using a stochastic representation provided by Wiener-regularized path integrals for the semigroups generated by certain Berezin-Toeplitz operators, a transformation formula for their resolvents is derived. The key property used in the transformation of the stochastic representation is that, up to a time change, Brownian motion is invariant under harmonic morphisms. This result for Berezin-Toeplitz operators is obtained in analogy with a well-known technique generating relations among Schrödinger operators that was recently generalized to Riemannian manifolds [Wittich, J. Math. Phys. {\bf 41} (…

Landau-Hall States and Berezin-Toeplitz Quantization of Matrix Algebras

We argue that the Landau-Hall states provide a suitable framework for formulating the Berezin-Toeplitz quantization of classical functions on a Kähler phase space. We derive the star-products for such functions in this framework and generalize the Berezin-Toeplitz quantization to matrix-valued classical functions. We also comment on how this is related to different calculations of the effective action for Hall systems.

Berezin-Toeplitz quantization on Kaehler manifolds

We study the Berezin-Toeplitz quantization on Kaehler manifolds. We explain first how to compute various associated asymptotic expansions, then we compute explicitly the first terms of the expansion of the kernel of the Berezin-Toeplitz operators, and of the composition of two Berezin-Toeplitz operators. As application we estimate the norm of Donaldson's Q-operator.

Berezin-Toeplitz Quantization and Star Products for Compact Kaehler Manifolds

For compact quantizable Kähler manifolds certain naturally defined star products and their constructions are reviewed. The presentation centers around the Berezin-Toeplitz quantization scheme which is explained. As star products the Berezin-Toeplitz, Berezin, and star product of geometric quantization are treated in detail. It is shown that all three are equivalent. A prominent role is played by the Berezin transform and its asymptotic expansion. A few ideas on two general constructions of star products of separation of variables type by Karabegov and by Bordemann--Waldmann respectively are gi…

Berezin-Toeplitz Quantization in Real Polarizations with Toric Singularities

On a compact Kähler manifold $X$, Toeplitz operators determine a deformation quantization $(\operatorname{C}^\infty(X, \mathbb{C})[[\hbar]], \star)$ with separation of variables [10] with respect to transversal complex polarizations $T^{1, 0}X, T^{0, 1}X$ as $\hbar \to 0^+$ [15]. The analogous statement is proved for compact symplectic manifolds with transversal non-singular real polarizations [13]. In this paper, we establish the analogous result for transversal singular real polarizations on compact toric symplectic manifolds $X$. Due to toric singularities, half-form correction and localiza…

Deformation quantization of compact Kaehler manifolds by Berezin-Toeplitz quantization

For arbitrary compact quantizable Kaehler manifolds it is shown how a natural formal deformation quantization (star product) can be obtained via Berezin-Toeplitz operators. Results on their semi-classical behaviour (their asymptotic expansion) due to Bordemann, Meinrenken and Schlichenmaier are used in an essential manner. It is shown that the star product is null on constants and fulfills parity. A trace is constructed and the relation to deformation quantization by geometric quantization is given.

Berezin-Toeplitz quantization for lower energy forms

Let $M$ be an arbitrary complex manifold and let $L$ be a Hermitian holomorphic line bundle over $M$. We introduce the Berezin-Toeplitz quantization of the open set of $M$ where the curvature on $L$ is non-degenerate. The quantum spaces are the spectral spaces corresponding to $[0,k^{-N}]$ ($N>1$ fixed), of the Kodaira Laplace operator acting on forms with values in tensor powers $L^k$. We establish the asymptotic expansion of associated Toeplitz operators and their composition as $k\to\infty$ and we define the corresponding star-product. If the Kodaira Laplace operator has a certain spectral …

扰动Berezin-Toeplitz算子的概率Weyl律

A probabilistic Weyl-law for perturbed Berezin-Toeplitz operators

本文证明随机扰动Berezin-Toeplitz算子谱的概率Weyl律，推广Vogel 2020年结果，采用其策略及作者发展的奇异符号演算。

Berezin-Toeplitz 算子的奇异演算

An exotic calculus of Berezin-Toeplitz operators

本文针对紧致 Kähler 流形上导数增长受局部几何与线丛幂控制的奇异光滑函数，建立了 Berezin-Toeplitz 算子演算，并利用复稳定相位法得到函数演算、迹公式与拟基本解构造，进而证明了随机扰动 Berezin-Toeplitz 算子的概率 Weyl 律。

Entanglement entropy and Berezin-Toeplitz operators

We consider Berezin-Toeplitz operators on compact Kahler manifolds whose symbols are characteristic functions. When the support of the characteristic function has a smooth boundary, we prove a two-term Weyl law, the second term being proportional to the Riemannian volume of the boundary. As a consequence, we deduce the area law for the entanglement entropy of integer quantum Hall states. Another application is for the determinantal processes with correlation kernel the Bergman kernels of a positive line bundle : we prove that the number of points in a smooth domain is asymptotically normal.

Semiclassical quantization and spectral limits of h-pseudodifferential and Berezin-Toeplitz operators

We introduce a minimalistic notion of semiclassical quantization and use it to prove that the convex hull of the semiclassical spectrum of a quantum system given by a collection of commuting operators converges to the convex hull of the spectrum of the associated classical system. This gives a quick alternative solution to the isospectrality problem for quantum toric systems. If the operators are uniformly bounded, the convergence is uniform. Analogous results hold for non-commuting operators.

Berezin-Toeplitz 算子的量子传播

Quantum propagation for Berezin-Toeplitz operators

本文研究实值主符号的 Berezin-Toeplitz 算子生成的量子传播子及自治情形下平滑谱投影的渐近行为，引入浸入拉格朗日子流形相关的量子态，主要贡献在于涉及预量子丛与典范丛提升的几何量，并与 Maslov 指标相关。

非自伴 Berezin–Toeplitz 算子与复拉格朗日态的正则 Bohr–Sommerfeld 规则

Regular Bohr-Sommerfeld rules for non-self-adjoint Berezin--Toeplitz operators and complex Lagrangian states

本文在能量水平正则性条件下，给出了复一维紧流形上非自伴 Berezin–Toeplitz 算子特征值和特征向量的指数小误差描述，建立了复版本的 Bohr–Sommerfeld 量子化规则，并为此发展了与复拉格朗日子流形相关的傅里叶积分算子与拉格朗日态演算工具。

Berezin-Toeplitz quantization over matrix domains

We explore the possibility of extending the well-known Berezin-Toeplitz quantization to reproducing kernel spaces of vector-valued functions. In physical terms, this can be interpreted as accommodating the internal degrees of freedom of the quantized system. We analyze in particular the vector-valued analogues of the classical Segal-Bargmann space on the domain of all complex matrices and of all normal matrices, respectively, showing that for the former a semi-classical limit, in the traditional sense, does not exist, while for the latter only a certain subset of the quantized observables have…

Berezin-Toeplitz quantization asssociated with higher Landau levels of the Bochner Laplacian

In this paper, we construct a family of Berezin-Toeplitz type quantizations of a compact symplectic manifold. For this, we choose a Riemannian metric on the manifold such that the associated Bochner Laplacian has the same local model at each point (this is slightly more general than in almost-Kähler quantization). Then the spectrum of the Bochner Laplacian on high tensor powers $L^p$ of the prequantum line bundle $L$ asymptotically splits into clusters of size ${\mathcal O}(p^{3/4})$ around the points $pΛ$, where $Λ$ is an eigenvalue of the model operator (which can be naturally called a Landa…

Toeplitz operators on symplectic manifolds

We study the Berezin-Toeplitz quantization on symplectic manifolds making use of the full off-diagonal asymptotic expansion of the Bergman kernel. We give also a characterization of Toeplitz operators in terms of their asymptotic expansion. The semi-classical limit properties of the Berezin-Toeplitz quantization for non-compact manifolds and orbifolds are also established.

Noncommutative coherent states and related aspects of Berezin-Toeplitz quantization

In~this paper, we construct noncommutative coherent states using various families of unitary irreducible representations (UIRs) of $\g$, a connected, simply connected nilpotent Lie group, that was identified as the kinematical symmetry group of noncommutative quantum mechanics for a system of 2-degrees of freedom in an earlier paper. Likewise described are the degenerate noncommutative coherent states arising from the degenerate UIRs of $\g$. We~then compute the reproducing kernels associated with both these families of coherent states and study Berezin-Toeplitz quantization of the observables…

Deformation quantization of compact Kähler manifolds via Berezin-Toeplitz operators

This talk reports on results on the deformation quantization (star products) and on approximative operator representations for quantizable compact K"ahler manifolds obtained via Berezin-Toeplitz operators. After choosing a holomorphic quantum line bundle the Berezin-Toeplitz operator associated to a differentiable function on the manifold is the operator defined by multiplying global holomorphic sections of the line bundle with this function and projecting the differentiable section back to the subspace of holomorphic sections. The results were obtained in (respectively based on) joint work wi…

关于Berezin-Toeplitz算子的伪谱

On the pseudospectra of Berezin-Toeplitz operators

本文在半经典极限下估计非自伴Berezin-Toeplitz算子预解式范数，负括号时构造局域伪模，证明数值值域收敛于符号像凸包，方法基于Hermite分布与次椭圆理论。

Berezin-Toeplitz Quantization of compact Kaehler manifolds

Invited lecture at the XIV-th workshop on geometric methods in physics, Bialowieza, Poland, July 9-15, 1995. In this lecture results are reviewed obtained by the author together with Martin Bordemann and Eckhard Meinrenken on the Berezin-Toeplitz quantization of compact Kaehler manifolds. Using global Toeplitz operators, approximation results for the quantum operators are shown. From them it follows that the quantum operators have the correct classical limit. A star product deformation of the Poisson algebra is constructed.

Lower order asymptotics for Szegö and Toeplitz kernels under Hamiltonian circle actions

We consider a natural variant of Berezin-Toeplitz quantization of compact Kähler manifolds, in the presence of a Hamiltonian circle action lifting to the quantizing line bundle. Assuming that the moment map is positive, we study the diagonal asymptotics of the associated Szegö and Toeplitz operators, and specifically their relation to the moment map and to the geometry of a certain symplectic quotient. When the underlying action is trivial and the moment map is taken to be identically equal to one, this scheme coincides with the usual Berezin-Toeplitz quantization. This continues previous work…

与Berezin--Toeplitz算子相关的二维行列式过程的波动

Fluctuations of two-dimensional determinantal processes associated with Berezin--Toeplitz operators

本文研究由Berezin--Toeplitz算子自由费米子基态导出的新行列式点过程，推广Ginibre系综，证明Szegő型展开并得到中心极限定理，揭示边界波动依赖哈密顿动力学且非共形不变。

Berezin-Toeplitz quantization on Lie groups

Let K be a connected compact semisimple Lie group and Kc its complexification. The generalized Segal-Bargmann space for Kc, is a space of square-integrable holomorphic functions on Kc, with respect to a K-invariant heat kernel measure. This space is connected to the "Schrodinger" Hilbert space L^2(K) by a unitary map, the generalized Segal-Bargmann transform. This paper considers certain natural operators on L^2(K), namely multiplication operators and differential operators, conjugated by the generalized Segal-Bargmann transform. The main results show that the resulting operators on the genera…

Berezin-Toeplitz operators, Kodaira maps, and random sections

We study the zeros of sections of the form $T_k s_k$ of a large power $L^{\otimes k} \to M$ of a holomorphic positive Hermitian line bundle over a compact K\''ahler manifold $M$, where $s_k$ is a random holomorphic section of $L^{\otimes k}$ and $T_k$ is a Berezin-Toeplitz operator, in the limit $k \to +\infty$. In particular, we compute the second order approximation of the expectation of the distribution of these zeros. In a ball of radius of order $k^{-\frac{1}{2}}$ around $x \in M$, assuming that the principal symbol $f$ of $T_k$ is real-valued and vanishes transversally, we show that this…

Toeplitz 算子与平方可积随机全纯截面的零点

Toeplitz operators and zeros of square-integrable random holomorphic sections

本文利用抽象 Wiener 空间理论，在完备 Hermitian 复流形上构建了 Berezin-Toeplitz 量子化的概率模型，将紧支集函数与平方可积 Gaussian 全纯截面关联，证明了半经典极限下随机零点的等分布、大偏差估计及中心极限定理。

Sharp correspondence principle and quantum measurements

We prove sharp remainder bounds for the Berezin-Toeplitz quantization and present applications to semiclassical quantum measurements.

非紧致流形的伯格曼-托普利茨量子化

Berezin-Toeplitz Quantization of non-compact manifolds

本文研究非紧致复几何背景下伯格曼-托普利茨量子化的性质，证明了在满足特定谱间隙条件下的Bergman投影的衰减性和渐进行为，并给出了托普利茨算子的闭包代数和星积结构。

Spectral aspects of the Berezin transform

We discuss the Berezin transform, a Markov operator associated to positive operator valued measures (POVMs), in a number of contexts including the Berezin-Toeplitz quantization, Donaldson's dynamical system on the space of Hermitian products on a complex vector space, representations of finite groups, and quantum noise. In particular, we calculate the spectral gap for quantization in terms of the fundamental tone of the phase space. Our results confirm a prediction of Donaldson for the spectrum of the Q-operator on Kahler manifolds with constant scalar curvature. Furthermore, viewing POVMs as …

Positive Quantization in the Presence of a Variable Magnetic Field

Starting with a previously constructed family of coherent states, we introduce the Berezin quantization for a particle in a variable magnetic field and we show that it constitutes a strict quantization of a natural Poisson algebra. The phase-space reinterpretation involves a magnetic version of the Bargmann space and leads naturally to Berezin-Toeplitz operators.

复射影空间量子化中的最优余项估计

Optimal Remainder Estimates in the Quantization of Complex Projective Spaces

本文研究复射影空间的 Berezin-Toeplitz 量子化，通过完全渐近展开和算子不等式得到正则性最优且常数精确或渐近精确的余项估计。

Deformation quantization via Toeplitz operators on geometric quantization in real polarizations

In this paper, we study quantization on a compact integral symplectic manifold $X$ with transversal real polarizations. In the case of complex polarizations, namely $X$ is Kähler equipped with transversal complex polarizations $T^{1, 0}X, T^{0, 1}X$, geometric quantization gives $H^0(X, L^{\otimes k})$'s. They are acted upon by $\mathcal{C}^\infty(X, \mathbb{C})$ via Toeplitz operators as $\hbar = \tfrac{1}{k} \to 0^+$, determining a deformation quantization $(\mathcal{C}^\infty(X, \mathbb{C})[[\hbar]], \star)$ of $X$.\par We investigate the real analogue to these, comparing deformation quanti…

Hermite Polynomials and Quasi-classical Asymptotics

We study an unorthodox variant of the Berezin-Toeplitz type of quantization scheme, on a reproducing kernel Hilbert space generated by the real Hermite polynomials and work out the associated semi-classical asymptotics.

The Spectrum of the Berezin transform for Gelfand pairs

We discuss the Berezin transform, a Markov operator associated to positive-operator valued measures (POVMs). We consider the class of so-called orbit POVMs, constructed on the quotient space $Ω= G/K$ of a compact group $G$ by its subgroup $K$. We restrict attention to the case where $(G, K)$ is a Gelfand pair and derive an explicit formula for the spectrum of the Berezin transform in terms of the characters of the irreducible unitary representations of $G$. We then specialize our results to the case study $G = \text{SU}(2)$ and $K \simeq S^1$, and find the spectra of orbit POVMs on $S^2$. We c…

通过微分算子对Kähler流形的量子化

Quantization of Kähler manifolds via differential operators

本文通过微分算子研究Kähler流形上经典可观测量的量子化，构造了Kostant-Souriau预量子微分算子的高阶推广，并证明了其与Berezin-Toeplitz算子的渐近等价性，同时给出了Berezin-Toeplitz算子成为全纯微分算子的完整刻画。

Berezin型量子化在偶数维紧致流形上的实现

Berezin-type quantization on even-dimensional compact manifolds

本文通过移除低维骨架将偶数维紧致流形嵌入复射影空间，实现Berezin型量子化，并给出环面实例及复流形的Berezin-Toeplitz量子化。

辛纤维化的量子化与典范度量

Quantization of symplectic fibrations and canonical metrics

本文通过Berezin-Toeplitz量子化与辛纤维化分步量子化的联系，研究向量丛的谱间隙及Donaldson迭代收敛到平衡度量的速率，并在标量情形给出精细估计。

Geometric quantization of symplectic maps and Witten's asymptotic conjecture

We use the theory of Berezin-Toeplitz operators of Ma and Marinescu to study the spaces of holomorphic sections of a prequantizing line bundle over compact Kähler manifolds under deformations of the complex structure. We show that the parallel transport in the induced vector bundle over the deformation space behaves like a Toeplitz operator, and compute its first coefficient. We then use this result to establish a semi-classical trace formula for the induced quantization of symplectic maps, and give an application to Witten's asymptotic expansion conjecture for the quantum representations of t…

Hitchin's connection, Toeplitz operators and symmetry invariant deformation quantization

We establish that Hitchin's connection exist for any rigid holomorphic family of Kahler structures on any compact pre-quantizable symplectic manifold which satisfies certain simple topological constraints. Using Toeplitz operators we prove that Hitchin's connection induces a unique formal connection on smooth functions on the symplectic manifold. Parallel transport of this formal connection produces equivalences between the corresponding Berezin-Toeplitz deformation quantizations. - In the cases where the Hitchin connection is projectively flat, the formal connections will be flat and we get a…

A new construction of strict deformation quantization for Lagrangian fiber bundles

We give a new construction of strict deformation quantization of symplectic manifolds equipped with a proper Lagrangian fiber bundle structure, whose representation spaces are the quantum Hilbert spaces obtained by geometric quantization. The construction can be regarded as a "lattice approximation of the correspondence between differential operators and principal symbols". We analyze the corresponding formal deformation quantization. We also investigate into relations between our construction and Berezin-Toeplitz deformation quantization.

Quantized Nambu-Poisson Manifolds and n-Lie Algebras

We investigate the geometric interpretation of quantized Nambu-Poisson structures in terms of noncommutative geometries. We describe an extension of the usual axioms of quantization in which classical Nambu-Poisson structures are translated to n-Lie algebras at quantum level. We demonstrate that this generalized procedure matches an extension of Berezin-Toeplitz quantization yielding quantized spheres, hyperboloids, and superspheres. The extended Berezin quantization of spheres is closely related to a deformation quantization of n-Lie algebras, as well as the approach based on harmonic analysi…

Berezin quantization of noncommutative projective varieties

We use operator algebras and operator theory to obtain new result concerning Berezin quantization of compact Kähler manifolds. Our main tool is the notion of subproduct systems of finite-dimensional Hilbert spaces, which enables all involved objects, such as the Toeplitz operators, to be very conveniently expressed in terms of shift operators compressed to a subspace of full Fock space. This subspace is not required to be contained in the symmetric Fock space, so from finite-dimensional matrix algebras we can construct noncommutative manifolds with extra structure generalizing that of a projec…

Singular projective varieties and quantization

By the quantization condition compact quantizable Kaehler manifolds can be embedded into projective space. In this way they become projective varieties. The quantum Hilbert space of the Berezin-Toeplitz quantization (and of the geometric quantization) is the projective coordinate ring of the embedded manifold. This allows for generalization to the case of singular varieties. The set-up is explained in the first part of the contribution. The second part of the contribution is of tutorial nature. Necessary notions, concepts, and results of algebraic geometry appearing in this approach to quantiz…

Branes, Quantization and Fuzzy Spheres

We propose generalized quantization axioms for Nambu-Poisson manifolds, which allow for a geometric interpretation of n-Lie algebras and their enveloping algebras. We illustrate these axioms by describing extensions of Berezin-Toeplitz quantization to produce various examples of quantum spaces of relevance to the dynamics of M-branes, such as fuzzy spheres in diverse dimensions. We briefly describe preliminary steps towards making the notion of quantized 2-plectic manifolds rigorous by extending the groupoid approach to quantization of symplectic manifolds.