Let X' be the toroidal compactification of the quotient of the complex 2-ball by a torsion free lattice G of SU(2,1). We say that X'is co-abelian if there is an abelian surface, birational to X'. The present work can be viewed as an illustration for the presence of a plenty of...
摘要: We completely determine all commutative semigroup varieties that are upper-modular elements of the lattice of all semigroup varieties. It is verified that if a semigroup variety is an upper-modular element of this lattice and different from the variety of all semigroups then it is a pe...
Let $\\\Gamma$ be a torsion free lattice in $G=\\\PGL(3,{{\\\mathbb F}})$ where ${{\\\mathbb F}}$ is a nonarchimedean local field. Then $\\\Gamma$ act... G Robertson,T Steger - 《Canad.j.math》 被引量: 86发表: 2001年 Stability of asymptotically AdS wormholes in vacuum...
Each M V-algebra A can be represented by means of an appropriate abelian lattice ordered group G with a strong unit u. (Cf. [4], [5], [7].) We denote by Co... J Jakubík - 《Czechoslovak Mathematical Journal》 被引量: 26发表: 1999年 Large subdirect products of graded modules Lar...
The first isa metabelian residually torsion-free-nilpotent groupGGF=Rhaving free central extensionF=½F;Rwhich is not residually nilpotent and the second is a centrally ordered group thatdoes not belong to the variety of lattice-ordered groups generated by all nilpotent lattice-ordered groups....
·Η—* 1,where Η is the finite holonomy group of X andM is a faithful integral representationof H (an H-lattice). FurthermoreΓis torsion-freeand the center C {Γ) of Γ is trivial.Conversely given such an Η, M andΓthere exists a corresponding flat manifold X.The main result ...
Let R be a principal ideal domain with quotient field F. An R-lattice is a free R-module of finite rank spanning an inner product space over F. The classif... LJ Gerstein - 《Journal of Algebra》 被引量: 19发表: 2003年 加载更多来源...
Free but not recursively free arrangements We construct counterexamples to the conjecture that every free arrangement is recursively free in characteristic zero. The intersection lattice of our smal... M Cuntz,T Hoge - 《Proc.amer.math.soc》 被引量: 16发表: 2015年 ...
quasivariety latticeLetLq(qG) be a lattice of quasivarieties contained in a quasivariety generated by a groupG. It is proved that ifGis a torsion-free finitely generated group in\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{...
torsion-free partZiegler spectrumDedekind domainsWe study the R-torsion-free part of the Ziegler spectrum of an order Λ over a Dedekind domain R.We underline and comment on the role of lattices over Λ.We describe the torsion-free part of the spectrum when Λ is of finite lattice ...