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Related papers: Harmonic morphisms from the Grassmannians and thei…

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We prove local existence of complex-valued harmonic morphisms from any Riemannian homogeneous spaces of positive curvature, except the Berger space Sp(2)/SU(2).

Differential Geometry · Mathematics 2019-02-20 Sigmundur Gudmundsson , Martin Svensson

In this work we use the method of eigenfamilies to construct explicit complex-valued proper $p$-harmonic functions on the compact real Grassmannians. We also find proper $p$-harmonic functions on the real flag manifolds which do not descend…

Differential Geometry · Mathematics 2023-07-27 Elsa Ghandour , Sigmundur Gudmundsson

We obtain a combinatorial expression for the coefficients of the boundary map of real isotropic and odd orthogonal Grassmannians providing a natural generalization of the formulas already obtained for Lagrangian and maximal isotropic…

Algebraic Topology · Mathematics 2023-03-10 Jordan Lambert , Lonardo Rabelo

In this paper we review some connections between harmonic analysis and the modern theory of automorphic forms. We indicate in some examples how the study of problems of harmonic analysis brings us to the important objects of the theory of…

Representation Theory · Mathematics 2012-12-24 Marko Tadic

Inspired by the all-important conformal invariance of harmonic maps on two-dimensional domains, this article studies the relationship between biharmonicity and conformality. We first give a characterization of biharmonic morphisms,…

Differential Geometry · Mathematics 2008-04-11 E. Loubeau , Y. -L. Ou

We apply the method of eigenfamilies to construct new explicit complex-valued p-harmonic functions on the non-compact classical Lie groups, equipped with their natural semi-Riemannian metrics. We then employ this same approach to…

Differential Geometry · Mathematics 2023-03-12 Elsa Ghandour , Sigmundur Gudmundsson

We consider 5-dimensional Lie groups with left-invariant Riemannian metrics. For such groups we give a partial classification of left-invariant conformal foliations with minimal leaves of codimension 2. These foliations produce local…

Differential Geometry · Mathematics 2016-04-07 Sigmundur Gudmundsson

A differential form defined on a Riemannian manifold is said to harmonic if it is closed and co-closed. Harmonic differential forms are a natural multi-dimensional extension of the concept of analytic function of complex variable. In this…

Functional Analysis · Mathematics 2007-05-23 René Dáger , Arturo Presa

On non-K\"ahler manifolds the notion of harmonic maps is modified to that of Hermitian harmonic maps in order to be compatible with the complex structure. The resulting semilinear elliptic system is {\it not} in divergence form. The case of…

Differential Geometry · Mathematics 2009-02-27 Hans-Christoph Grunau , Marco Kuehnel

Pseudo-harmonic morphisms give rise on the domain space to a distribution which admits an almost complex structure compatible with the given Riemannian metric. We shall show that this property, together with the harmonicity, are preserved…

Differential Geometry · Mathematics 2007-05-23 Radu Slobodeanu

The present article studies holomorphic isometric embeddings of arbitrary complex Grassmannians into quadrics, generalising results in [13]. The moduli spaces of these embeddings up to gauge and image equivalence are discussed using a…

Differential Geometry · Mathematics 2022-06-29 Oscar Macia , Yasuyuki Nagatomo

We will pursue a way of building up an algebraic structure that involves, in a mathematical abstract way, the well known Grassmann variables. The problem arises when we tried to understand the grassmannian polynomial expansion on the scope…

Mathematical Physics · Physics 2007-05-23 Ricardo M Bentin

We present here a large collection of harmonic and quadratic harmonic sums, that can be useful in applied questions, e.g., probabilistic ones. We find closed-form formulae, that we were not able to locate in the literature.

Discrete Mathematics · Computer Science 2024-12-13 Krzysztof Bartoszek

In this paper we propose a new supersymmetric extension of conformal mechanics. The Grassmannian variables that we introduce are the basis of the forms and of the vector-fields built over the symplectic space of the original system. Our…

High Energy Physics - Theory · Physics 2015-06-26 E. Deotto , G. Furlan , E. Gozzi

Within the framework of the recently proposed formalism using non-hermitean Hamiltonians constrained merely by their PT invariance we describe a new exactly solvable family of the harmonic-oscillator-like potentials with non-equidistant…

Quantum Physics · Physics 2009-10-31 Miloslav Znojil

We describe the relationship between complex-valued harmonic morphisms from Minkowski 4-space} and the shear-free ray congruences of mathematical physics. Then we show how a horizontally conformal submersion on a domain of Euclidean 3-space…

Differential Geometry · Mathematics 2007-05-23 P. Baird , J. C. Wood

While real Hamiltonian mechanics and Hermitian quantum mechanics can both be cast in the framework of complex canonical equations, their complex generalisations have hitherto been remained tangential. In this paper quaternionic and…

Mathematical Physics · Physics 2015-03-17 Dorje C Brody , Eva-Maria Graefe

We develop the version of the $J$-invariant for hermitian forms over quadratic extensions in a similar way Alexander Vishik did it for quadratic forms. This discrete invariant contains informations about rationality of algebraic cycles on…

Algebraic Geometry · Mathematics 2019-08-14 Raphaël Fino

There is considered the problem of describing up to linear conformal equivalence those harmonic cubic homogeneous polynomials for which the squared-norm of the Hessian is a nonzero multiple of the quadratic form defining the Euclidean…

Rings and Algebras · Mathematics 2023-05-15 Daniel J. F. Fox

A matrix algebra is constructed which consists of the necessary degrees of freedom for a finite approximation to the algebra of functions on the family of orthogonal Grassmannians of real dimension 2N, known as complex quadrics. These…

High Energy Physics - Theory · Physics 2009-11-10 Brian P. Dolan , Denjoe O'Connor , Peter Presnajder