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Johannes Wittmann 《Mathematische Nachrichten》2019,292(7):1627-1635
Let M be a closed spin manifold and let N be a closed manifold. For maps and Riemannian metrics g on M and h on N, we consider the Dirac operator of the twisted Dirac bundle . To this Dirac operator one can associate an index in . If M is 2‐dimensional, one gets a lower bound for the dimension of the kernel of out of this index. We investigate the question whether this lower bound is obtained for generic tupels . 相似文献
3.
Palle E.T. Jorgensen Erin P.J. Pearse 《Journal of Mathematical Analysis and Applications》2019,469(2):765-807
Motivated by applications to machine learning, we construct a reversible and irreducible Markov chain whose state space is a certain collection of measurable sets of a chosen l.c.h. space . We study the resulting network (connected undirected graph), including transience, Royden and Riesz decompositions, and kernel factorization. We describe a construction for Hilbert spaces of signed measures which comes equipped with a new notion of reproducing kernels and there is a unique solution to a regularized optimization problem involving the approximation of functions by functions of finite energy. The latter has applications to machine learning (for Markov random fields, for example). 相似文献
4.
Hugo M. Campos Vladislav V. Kravchenko 《Mathematical Methods in the Applied Sciences》2020,43(16):9448-9454
The paper extends some well-known results for analytic functions onto solutions of the Vekua equation regarding the existence and construction of the Bergman kernel and of the corresponding Bergman projection operator. 相似文献
5.
We generalize Nagel’s formula for the Szegö kernel and use it to compute the Szegö kernel on a class of non-compact CR manifolds whose tangent space decomposes into one complex direction and several totally real directions. We also discuss the control metric on these manifolds and relate it to the size of the Szegö kernel. 相似文献
6.
Butylated hydroxytoluene enediyne: access to diradical and electrophilic quinone methide intermediates 下载免费PDF全文
Edyta M. Greer Cesar S. Quezada Christopher V. Cosgriff 《Journal of Physical Organic Chemistry》2015,28(5):365-369
A theoretical study was carried out on the unimolecular reaction of an enediyne with a fused butylated hydroxytoluene to internally scavenge the p‐benzyne diradical sites formed after the Bergman cyclization. The calculations revealed that the conversion of the p‐benzyne diradical (2‐tert‐butyl‐4‐methyl‐5,8‐didehydro‐1‐naphthalenol) to p‐quinone methide is favored over the conversion to a phenoxy/benzene diradical 4 in an approximate 95:5 ratio. Based on this model, the Bergman cyclization leads in a bifunctional manner to intermediates for competing reactivity with intermolecular H‐atom abstraction. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
7.
《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2020,37(5):1185-1209
We establish the existence of solutions of the Cauchy problem for a higher-order semilinear parabolic equation by introducing a new majorizing kernel. We also study necessary conditions on the initial data for the existence of local-in-time solutions and identify the strongest singularity of the initial data for the solvability of the Cauchy problem. 相似文献
8.
Shijun Zheng 《分析论及其应用》2006,22(4)
Let H be a Schr(o)dinger operator on Rn. Under a polynomial decay condition for the kernel of its spectral operator, we show that the Besov spaces and Triebel-Lizorkin spaces associated with H are well defined. We further give a Littlewood-Paley characterization of Lp spaces in terms of dyadic functions of H. This generalizes and strengthens the previous result when the heat kernel of H satisfies certain upper Gaussian bound. 相似文献
9.
We use holomorphic invariants to calculate the Bergman kernel for generalized quasi-homogeneous Reinhardt-Hartogs domains. In addition, we present a complete orthonormal basis for the Bergman space on bounded Reinhardt-Hartogs domains. 相似文献
10.