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Related papers: Almost Hermitian Identities

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We use the natural lifts of the fundamental tensor field g to the cotangent bundle T*M of a Riemannian manifold (M,g), in order to construct an almost Hermitian structure (G,J) of diagonal type on T*M. The obtained almost complex structure…

Differential Geometry · Mathematics 2007-05-23 Vasile Oproiu , Dumitru Daniel Porosniuc

These notes are intended to be an introduction to the use of approximately holomorphic techniques in almost contact and contact geometry. We develop the setup of the approximately holomorphic geometry. Once done, we sketch the existence of…

Symplectic Geometry · Mathematics 2012-11-21 Francisco Presas

We consider one-dimensional Schroedinger-type operators in a bounded interval with non-self-adjoint Robin-type boundary conditions. It is well known that such operators are generically conjugate to normal operators via a similarity…

Spectral Theory · Mathematics 2014-06-12 D. Krejcirik , P. Siegl , J. Zelezny

It is known that the almost-Kaehler anti-self-dual metrics on a given 4-manifold sweep out an open subset in the moduli space of anti-self-dual metrics. However, we show here by example that this subset is not generally closed, and so need…

Differential Geometry · Mathematics 2018-01-22 Christopher J. Bishop , Claude LeBrun

We consider the heat operator acting on differential forms on spaces with complete and incomplete edge metrics. In the latter case we study the heat operator of the Hodge Laplacian with algebraic boundary conditions at the edge singularity.…

Analysis of PDEs · Mathematics 2015-06-15 Eric Bahuaud , Emily B. Dryden , Boris Vertman

We study the space of pseudo-holomorphic spheres in compact symplectic manifolds with convex boundary. We show that the theory of Gromov-Witten invariants can be extended to the class of semi-positive manifolds with convex boundary. This…

Symplectic Geometry · Mathematics 2013-02-06 Sergei Lanzat

We obtain sharp uniform bounds on the low lying eigenfunctions for a class of semiclassical pseudodifferential operators with double characteristics and complex valued symbols, under the assumption that the quadratic approximations along…

Analysis of PDEs · Mathematics 2017-07-07 Katya Krupchyk , Gunther Uhlmann

We construct a parametrix of a resolvent of elliptic differential operators acting on half-densities on manifolds with ends. The construction is carried out by introducing suitable pseudodifferential operators compatible with the end…

Differential Geometry · Mathematics 2022-01-26 Shota Fukushima

. We study the statistical properties of the eigenvalues of non-Hermitian operators assoicated with the dissipative complex systems. By considering the Gaussian ensembles of such operators, a hierarchical relation between the correlators is…

Statistical Mechanics · Physics 2024-12-11 Pragya Shukla

We prove trace identities for commutators of operators, which are used to derive sum rules and sharp universal bounds for the eigenvalues of periodic Schroedinger operators and Schroedinger operators on immersed manifolds. In particular, we…

Spectral Theory · Mathematics 2009-03-04 Evans M. Harrell , Joachim Stubbbe

We give several applications of a recent theorem of the second author, which solved a conjecture of the first author with Hay and Neal, concerning contractive approximate identities; and another of Hay from the theory of noncommutative peak…

Operator Algebras · Mathematics 2011-02-22 David P. Blecher , Charles John Read

In this article, we consider the almost Hermitian structure on $TM$ induced by a pair of a metric and an affine connection on $M$. We find the conditions under which $TM$ admits almost K\"ahler structures, K\"ahler structures and Einstein…

Differential Geometry · Mathematics 2025-03-24 Hiroyasu Satoh

We study the space of nearly K\"{a}hler structures on compact 6-dimensional manifolds. In particular, we prove that the space of infinitesimal deformations of a strictly nearly K\"{a}hler structure (with scalar curvature scal) modulo the…

Differential Geometry · Mathematics 2019-01-08 Andrei Moroianu , Paul-Andi Nagy , Uwe Semmelmann

We consider a convolution-type operator on vector bundles over metric-measure spaces. This operator extends the analogous convolution Laplacian on functions in our earlier work to vector bundles, and is a natural extension of the graph…

Analysis of PDEs · Mathematics 2022-02-23 Dmitri Burago , Sergei Ivanov , Yaroslav Kurylev , Jinpeng Lu

Diagonalizable pseudo-Hermitian Hamiltonians with real and discrete spectra, which are superpartners of Hermitian Hamiltonians, must be $\eta$-pseudo-Hermitian with Hermitian, positive-definite and non-singular $\eta$ operators. We show…

Mathematical Physics · Physics 2010-04-14 Boris F. Samsonov , V. V. Shamshutdinova , A. V. Osipov

On a para-quaternionic K\"ahler manifold $(\widetilde M^{4n},Q,\widetilde g)$, which is first of all a pseudo-Riemannian manifold, a natural definition of (almost) K\"ahler and (almost) para-K\"ahler submanifold $(M^{2m},\mathcal{J},g)$ can…

Differential Geometry · Mathematics 2012-01-20 Massimo Vaccaro

We obtain a system of identities relating boundary coefficients and spectral data for the one-dimensional Schr\"{o}dinger equation with boundary conditions containing rational Herglotz--Nevanlinna functions of the eigenvalue parameter.…

Mathematical Physics · Physics 2025-04-30 Namig J. Guliyev

We consider a pair of smooth manifolds, which are the counterparts in the even-dimensional and odd-dimensional cases. They are separately an almost complex manifold with Norden metric and an almost contact manifolds with B-metric,…

Differential Geometry · Mathematics 2015-05-06 Mancho Manev

Non-degenerate real hypersurfaces of almost Hermite-like manifolds are examined. Tangential real hypersurfaces are introduced and the main identities of such hypersurfaces are obtained. With the help of these identities, contact metric…

Differential Geometry · Mathematics 2023-07-04 Esra Erkan , mehmet Gulbahar

We give manifolds in both the Riemannian and in the higher signature settings whose Riemann curvature operators commute, i.e. which satisfy R(a,b)R(c,d)=R(c,d)R(a,b) for all tangent vectors. These manifolds have global geometric phenomena…

Differential Geometry · Mathematics 2007-05-23 M. Brozos-Vazquez , P. Gilkey