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For a given manifold $M$ we consider the non-linear Grassmann manifold $Gr_n(M)$ of $n$-dimensional submanifolds in $M$. A closed $(n+2)$-form on $M$ gives rise to a closed 2-form on $Gr_n(M)$. If the original form was integral, the 2-form…

Differential Geometry · Mathematics 2007-05-23 Stefan Haller , Cornelia Vizman

It is shown that vielbeins and connections of any (super)space are naturally described in terms of nonlinear realizations of infinite - dimensional diffeomorphism groups of the corresponding (super)space. The method of construction of…

High Energy Physics - Theory · Physics 2007-05-23 A. Pashnev

We hypothesize that the vacuum is spontaneously shifted from the self-dual point in the moduli space, at which all dimensions are compact, and that the true vacuum results from the decompactification of the four space-time dimensions and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Y. Abe , C. Hattori , M. Ito , M. Matsunaga , T. Matsuoka

A bounded automorphism of a field or a group with trivial approximate centre is definable. In an expansion of a field by a Pfaffian family F of additive endomorphisms such that algebraic closure in the expansion coincides with relative…

Logic · Mathematics 2024-12-09 Frank Olaf Wagner

In this paper, we settle a long-standing problem on the connectivity of spaces of finite unit norm tight frames (FUNTFs), essentially affirming a conjecture first appearing in [Dykema and Strawn, 2003]. Our central technique involves…

Functional Analysis · Mathematics 2016-01-18 Jameson Cahill , Dustin G. Mixon , Nate Strawn

In this paper we extend results due to Vogt on line bundles over Cousin groups to the case of domains stable by the maximal compact subgroup. This is used in the sequel to show that the algebraic dimension of OT-manifolds is zero. In the…

Complex Variables · Mathematics 2015-10-08 Laurent Battisti , Karl Oeljeklaus

We prove that if $n$ is even, $(M,g)$ is a compact $n$-dimensional Riemannian manifold whose Pfaffian form is a positive multiple of the volume form, and $y\in C^{1,\alpha}(M;\mathbb{R}^{n+1})$ is an isometric immersion with $n/(n+1)<…

Differential Geometry · Mathematics 2016-09-15 Sören Behr , Heiner Olbermann

We construct rational models for classifying spaces of self-equivalences of bundles over simply connected finite CW-complexes relative to a given simply connected subcomplex. Via work of Berglund-Madsen and Krannich this specializes to…

Algebraic Topology · Mathematics 2025-01-06 Alexander Berglund , Robin Stoll

We characterise $n$th order ODEs for which the space of solutions $M$ is equipped with a particular paraconformal structure in the sense of \cite{BE}, that is a splitting of the tangent bundle as a symmetric tensor product of rank-two…

Differential Geometry · Mathematics 2009-11-11 Maciej Dunajski , Paul Tod

It is known that a two-dimensional bosonic theory with a non-anomalous $\mathbb{Z}_2$ symmetry can be fermionized. Recent work shows that if the bosonic theory also has non-anomalous time-reversal symmetry, fermionization extends to…

High Energy Physics - Theory · Physics 2026-05-26 Ippo Orii , Keita Tsuji

Twin groups and virtual twin groups are planar analogues of braid groups and virtual braid groups, respectively. These groups play the role of braid groups in the Alexander-Markov correspondence for the theory of stable isotopy classes of…

Group Theory · Mathematics 2025-10-17 Tushar Kanta Naik , Neha Nanda , Mahender Singh

We construct sphere fibrations over $(n-1)$-connected $2n$-manifolds such that the total space is a connected sum of sphere products. More precisely, for $n$ even, we construct fibrations $S^{n-1} \to \#^{k-1}(S^n \times S^{2n-1}) \to M_k$,…

Algebraic Topology · Mathematics 2023-08-31 Samik Basu , Aloke Kr. Ghosh

We study equivariant affine embeddings of homogeneous spaces and their equivariant automorphisms. An example of a quasiaffine, but not affine, homogeneous space with finitely many equivariant automorphisms is presented. We prove the…

Algebraic Geometry · Mathematics 2009-10-03 Ivan V. Arzhantsev , Dmitri A. Timashev

We construct novel fermion-fermion dualities in $2+1$-dimensions using 3d bosonization dualities. This is achieved by relating two-node quiver theories using both the flavor-bounded and flavor-violated 3d bosonization dualities. Such…

High Energy Physics - Theory · Physics 2020-01-29 Kyle Aitken , Changha Choi , Andreas Karch

A manifold $M$ is said to be a double disk bundle if it can be decomposed as a union of two disk bundles glued together by a diffeomorphism of their boundaries. We show that if $M^n$ is a closed simply connected $n$-manifold with $n$ even…

Differential Geometry · Mathematics 2026-05-12 Jason DeVito , Martin Kerin

This is the second part of a two part work in which we prove that for every finitely generated subgroup $\Gamma < \mathsf{Out}(F_n)$, either $\Gamma$ is virtually abelian or its second bounded cohomology $H^2_b(\Gamma;\mathbb{R})$ contains…

Group Theory · Mathematics 2025-03-12 Michael Handel , Lee Mosher

The group action which defines the moduli problem for the deformation space of flat affine structures on the two-torus is the action of the affine group $\Aff(2)$ on $\bbR^2$. Since this action has non-compact stabiliser $\GL(2,\bbR)$, the…

Differential Geometry · Mathematics 2011-12-15 Oliver Baues

In [BK], it is shown that the Turaev-Viro invariants defined for a spherical fusion category $\mathcal{A}$ extends to invariants of 3-manifolds with corners. In [Kir], an equivalent formulation for the 2-1 part of the theory (2-manifolds…

Quantum Algebra · Mathematics 2022-11-01 Alexander Kirillov , Ying Hong Tham

This is the first in a series of four papers (with research announcement posted on this arXiv) that together develop a decomposition theory for subgroups of Out(F_n). In this paper we develop further the theory of geometric EG strata of…

Group Theory · Mathematics 2013-06-24 Michael Handel , Lee Mosher

In [22], Crane and Sheppard considered the structure of the Poincare group as a 2-Group, and derived important information about its representations in a 2-Category suited for representations of non-compact 2-groups, following a lead of…

Mathematical Physics · Physics 2011-12-30 Dany Majard