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Let $A$ be a ring with $1\neq 0$, not necessarily finite, endowed with an involution~$*$, that is, an anti-automorphism of order $\leq 2$. Let $H_n(A)$ be the additive group of all $n\times n$ hermitian matrices over $A$ relative to $*$.…

Representation Theory · Mathematics 2016-11-02 Fernando Szechtman

Let $RG$ be the gruop ring of the group $G$ over ring $R$ and $\mathscr{U}(RG)$ be its unit group. Finding the structure of the unit group of a finite group ring is an old topic in ring theory. In, G. Tang et al: Unit Groups of Group…

Rings and Algebras · Mathematics 2020-04-08 Ali Ashja'

For a reductive group over a nonarchimedean local field, we define the stack of spherical Langlands parameters, using the inertia-invariants of the Langlands dual group. This generalizes the stack of unramified Langlands parameters in case…

Number Theory · Mathematics 2025-10-30 Thibaud van den Hove

We give extensions of results on nonnegative matrix semigroups which deduce finiteness or boundedness of such semigroups from the corresponding local properties, e.g., from finiteness or boundedness of values of certain linear functionals…

Functional Analysis · Mathematics 2013-07-01 Roman Drnovšek , Heydar Radjavi

The paper discusses progress in understanding statistical properties of complex eigenvalues (and corresponding eigenvectors) of weakly non-unitary and non-Hermitian random matrices. Ensembles of this type emerge in various physical…

Chaotic Dynamics · Physics 2009-11-07 Yan V Fyodorov , H. -J Sommers

Let G be an unramified reductive group over a non archimedian local field F. The so-called "Langlands Fundamental Lemma" is a family of conjectural identities between orbital integrals for G(F) and orbital integrals for endoscopic groups of…

Algebraic Geometry · Mathematics 2007-05-23 G. Laumon , B. C. Ngo

We construct several families of embeddings of braid groups into mapping class groups of orientable and non-orientable surfaces and prove that they induce the trivial map in stable homology in the orientable case, but not so in the…

Algebraic Topology · Mathematics 2012-04-20 Carl-Friedrich Bödigheimer , Ulrike Tillmann

In this article, we study local models associated to certain Shimura varieties. In particular, we present a resoultion of their singularities. As a consequence, we are able to determine the alternating semisimple trace of the geometric…

Algebraic Geometry · Mathematics 2007-05-23 Nicole Kraemer

It this note we investigate the structure of the group of \sigma-unitary units in some noncommutative modular group algebras KG, where \sigma is a non-classical ring involution of KG.

Rings and Algebras · Mathematics 2008-03-04 Victor Bovdi , Tibor Rozgonyi

We construct a model of the Hermitian unital of order 3 (obtained from the non-degenerate hermitian form in three variables over the field of order 9) inside the octonion algebra over the field of order 2. This construction is invariant…

Group Theory · Mathematics 2025-09-30 Markus J. Stroppel

We obtain criteria for when a ring with enough idempotents is left/right artinian or noetherian in terms of local criteria defined by the associated complete set of idempotents for the ring. We apply these criteria to object unital category…

Rings and Algebras · Mathematics 2022-04-05 Patrik Lundström

This work concerns finite free complexes over commutative noetherian rings, in particular over group algebras of elementary abelian groups. The main contribution is the construction of complexes such that the total rank of their underlying…

Commutative Algebra · Mathematics 2018-05-11 Srikanth B. Iyengar , Mark E. Walker

In recent years, centrally essential rings have been intensively studied in ring theory. In particular, they find applications in homological algebra, group rings, and the structural theory of rings. The class of essentially central rings…

Rings and Algebras · Mathematics 2022-04-22 Askar Tuganbaev

In this paper the concept of local embeddability into finite structures (being LEF) for the class of semigroups is expanded with investigations of non-LEF structures, a closely related generalising property of local wrapping of finite…

Group Theory · Mathematics 2023-10-09 Dmitry Kudryavtsev

We study the complex irreducible representations of special linear, symplectic, orthogonal and unitary groups over principal ideal local rings of length two. We construct a canonical correspondence between the irreducible representations of…

Representation Theory · Mathematics 2011-04-25 Pooja Singla

Suppose $G$ is a locally solid lattice group. It is known that there are non-equivalent classes of bounded homomorphisms on $G$ which have topological structures. In this paper, our attempt is to assign lattice structures on them. More…

Functional Analysis · Mathematics 2019-09-06 Omid Zabeti

We investigate the similarities between adic finiteness and homological finiteness for chain complexes over a commutative noetherian ring. In particular, we extend the isomorphism properties of certain natural morphisms from homologically…

Commutative Algebra · Mathematics 2016-02-25 Sean Sather-Wagstaff , Richard Wicklein

We prove that all linear Lie groups satisfying the conditions listed in the title are finite extensions of commutative Lie groups.

Representation Theory · Mathematics 2025-10-14 A. I. Shtern

A notion of fundamental group of spectral triples has been introduced. The notion uses a noncommutative analogue of unramified coverings. It was shown that in commutative case this fundamental group is a profinite completion of fundamental…

K-Theory and Homology · Mathematics 2007-05-23 Petr R. Ivankov , Nickolay P. Ivankov

We discuss the time evolution of physical finite dimensional systems which are modelled by non-hermitian Hamiltonians. We address both general non-hermitian Hamiltonians and pseudo-hermitian ones. We apply the theory of Krein Spaces to…

Mathematical Physics · Physics 2019-01-30 R. Ramirez , M. Reboiro