Results 41 to 50 of about 6,087,542 (164)
Geometric inverse semigroup theory: a note on the Milnor–Schwarz lemma for inverse monoids
Bulletin of the London Mathematical Society, Volume 58, Issue 9, September 2026.Abstract We generalise the Milnor–Schwarz lemma to inverse monoids acting on presheaves of geodesic metric spaces. We provide two proofs of this fact: one only uses elementary techniques, inspired by the arguments for group actions on metric spaces; the other involves a version of the Vietoris–Rips complex, and builds on work of Chung–Martínez–Szakács.
Giorgio Mangioni, Francesco Tesolin
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Feller semigroups, Lp-sub-Markovian semigroups, and applications to pseudo-differential operators with negative definite symbols [PDF]
, 2001 The question of extending L-p-sub-Markovian semigroups to the spaces L-q, q > P, and the interpolation of LP-sub-Markovian semigroups with Feller semigroups is investigated.
Farkas, Walter +4 more
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Maximal semigroups in finitely generated nilpotent groups
Proyecciones (Antofagasta), 2018 We obtain a classification of maximal subsemigroups of finitely generated nilpotent groups. In the principal results of this paper we show that there is a one-to-one correspondence between these subsemigroups and the non trivial homomorphisms of the group in R.
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Cartwright–Sturmfels Hilbert schemes
Journal of the London Mathematical Society, Volume 114, Issue 3, September 2026.Abstract Let S$S$ be the Cox ring of a product of r$r$ projective spaces. In this paper, we study the Cartwright–Sturmfels Hilbert schemes of S$S$, which are multigraded Hilbert schemes that parameterize only radical ideals. Our main result shows that these Hilbert schemes are always smooth and irreducible if the Picard rank r$r$ is at most 2.
Ritvik Ramkumar, Alessio Sammartano
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Equidistribution in 2‐nilpotent Polish groups and triple restricted sumsets
Journal of the London Mathematical Society, Volume 114, Issue 3, September 2026.Abstract The aim of this paper is to establish a Ratner‐type equidistribution theorem for orbits on homogeneous spaces associated with 2$\hskip.001pt 2$‐nilpotent locally compact Polish groups under the action of a countable discrete abelian group.
Ethan Ackelsberg, Asgar Jamneshan
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On semigroups generated by differential operators on Lie groups
Journal of Functional Analysis, 1979 AbstractLet dR be the differential of a strongly continuous representation of a Lie group G on a Hilbert space H. Let P be the left-invariant second-order differential operator on G with positive semidefinite main part P2 and with first-order part P1.
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Higher representation stability for ordered configuration spaces
Journal of Topology, Volume 19, Issue 3, September 2026.Abstract Using factorization homology with coefficients in twisted commutative algebras (TCAs), we prove two flavors of higher representation stability for the cohomology of (generalized) configuration spaces of a scheme/topological space X$X$. First, we provide an iterative procedure to study higher representation stability using actions coming from ...
Quoc P. Ho
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Invariant Measure and Universality of the 2D Yang–Mills Langevin Dynamic
Communications on Pure and Applied Mathematics, Volume 79, Issue 8, Page 1973-2102, August 2026.ABSTRACT We prove that the Yang–Mills (YM) measure for the trivial principal bundle over the two‐dimensional torus, with any connected, compact structure group, is invariant for the associated renormalised Langevin dynamic. Our argument relies on a combination of regularity structures, lattice gauge‐fixing and Bourgain's method for invariant measures ...
Ilya Chevyrev, Hao Shen
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, 2012 In this thesis we consider in detail the following two fundamental problems for semigroup presentations: 1. Given a semigroup find a presentation defining it. 2. Given a presentation describe the semigroup defined by it.
Ruškuc, Nik
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On the theories classified by an étendue
Bulletin of the London Mathematical Society, Volume 58, Issue 7, July 2026.Abstract We give a model‐theoretic characterisation of the geometric theories classified by étendues—the ‘locally localic’ topoi. They are the theories where each model is determined, syntactically and semantically, by any witness of a fixed collection of formulae.
Joshua L. Wrigley
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