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Let F be a K\"ahler foliation on a compact Riemannian manifold M. we study the properties of infinitesimal automorphisms on (M,F), and in particular we concentrate on the transversal conformal field, transversal projective field and…

Differential Geometry · Mathematics 2011-06-03 Seoung Dal Jung

We study obstructions to the existence of Riemannian metrics of positive scalar curvature on closed smooth manifolds arising from torsion classes in the integral homology of their fundamental groups. As an application, we construct new…

Differential Geometry · Mathematics 2024-07-31 Misha Gromov , Bernhard Hanke

We will introduce formal frames of manifolds, which are a generalization of ordinary frames. Their fundamental properties are discussed. In particular, canonical forms are introduced, and torsions are defined in terms of them as a…

Differential Geometry · Mathematics 2023-03-15 Taro Asuke

We construct a Parseval frame with $n+1$ vectors in $\R^n$ that contains a given vector. We also provide a characterization of unit-norm frames that can be scaled to a Parseval frame.

Functional Analysis · Mathematics 2013-09-17 Laura De Carli , Zhongyuan Hu

In this paper, we introduce the concept of multivalued $\lambda $% -contracting perimeters of triangles. This concept generalizes the Nadler's contraction by considering triplets of points instead of pairs. Fundamental properties of such…

Functional Analysis · Mathematics 2026-05-14 Hakan Sahin , Mustafa Aslantas , Ishak ALtun

For central simple algebras of exponent $2$ over fields of characteristic $2$ and $2$-cohomological dimension equal to $2$, we study the adapted decomposition to some multiquadratic extensions of the base field. Several remarkable…

Rings and Algebras · Mathematics 2022-04-26 Demba Barry , Ahmed Laghribi

We provide a functional characterization of isometries between non-reversible Finsler manifolds, in the form of a generalization of the Myers-Nakai Theorem for Riemannian manifolds. We show that, since non-reversible Finsler manifolds are a…

Functional Analysis · Mathematics 2025-01-07 Francisco Venegas M

Motivated by showing that in ZFC we cannot construct a special Aronszajn tree on some cardinal greater than $\aleph_1$, we produce a model in which the approachability property fails (hence there are no special Aronszajn trees) at all…

Logic · Mathematics 2018-06-12 Spencer Unger

We prove that up to birational equivalence, there exists only a finite number of families of Calabi-Yau threefolds (i.e. a threefold with trivial canonical class and factorial terminal singularities) which have an elliptic fibration to a…

alg-geom · Mathematics 2008-02-03 M. Gross

We prove that every finitely generated group with recursive aspherical presentation embeds into a group with finite aspherical presentation. This and several known facts about groups and manifolds imply that there exists a 4-dimensional…

Group Theory · Mathematics 2011-04-27 Mark Sapir

We present a new construction for obtaining pairs of higher-step isospectral Riemannian nilmanifolds and compare several resulting new examples. In particular, we present new examples of manifolds that are isospectral on functions, but not…

Differential Geometry · Mathematics 2009-09-25 Ruth Gornet

We show that NIP fields have no Artin-Schreier extension, and that simple fields have only a finite number of them.

Logic · Mathematics 2010-09-29 Itay Kaplan , Thomas Scanlon , Frank O. Wagner

A classical theorem attributed to Naimark states that, given a Parseval frame $\mathcal{B}$ in a Hilbert space $\mathcal{H}$, one can embed $\mathcal{H}$ in a larger Hilbert space $\mathcal{K}$ so that the image of $\mathcal{B}$ is the…

Classical Analysis and ODEs · Mathematics 2014-09-25 Peter M. Luthy , Guido L. Weiss , Edward N. Wilson

In this paper we give a characterisation of trivial extension algebras in terms of quivers with relations. This result is based on a explicit description of the ideal of relations of the trivial extension of an algebra, given by the first…

Rings and Algebras · Mathematics 2022-06-22 Elsa Fernandez , Sibylle Schroll , Hipolito Treffinger , Sonia Trepode , Yadira Valdivieso

Let $(M,\mathcal{N})$ be a marked 3-manifold. We use $S_n(M,\mathcal{N},v)$ to denote the stated $SL_n$-skein module of $(M,\mathcal{N})$ where $v$ is a nonzero complex number. We establish a surjective algebra homomorphism from…

Geometric Topology · Mathematics 2024-01-29 Zhihao Wang

We prove the non-existence of real analytic Levi flat hypersurface whose complement is 1-convex and Levi foliation is transversely affine in compact Kahler surfaces.

Complex Variables · Mathematics 2022-09-20 Masanori Adachi , Severine Biard

We study valued fields equipped with an automorphism. We prove that all of them have an extension admitting an equivariant cross-section of the valuation. In residual characteristic zero, and in the presence of such a cross-section, we show…

Logic · Mathematics 2025-12-18 Jan Dobrowolski , Francesco Gallinaro , Rosario Mennuni

We proved a conjecture of D. Freed that there are no non-trivial complete special Kaehler manifolds.

Differential Geometry · Mathematics 2007-05-23 Zhiqin Lu

In this paper, we prove a similar result to the fundamental theorem of regular surfaces in classical differential geometry, which extends the classical theorem to the entire class of singular surfaces in Euclidean 3-space known as frontals.…

Differential Geometry · Mathematics 2019-10-08 Tito Alexandro Medina Tejeda

We prove a relative Kawamata Viehweg vanishing type theorem for birational morphisms. We use this to prove a Grauert Riemenschneider theorem over log canonical threefolds without zero dimensional log canonical centers, in residue…

Algebraic Geometry · Mathematics 2023-02-20 Emelie Arvidsson
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