Results 1 to 10 of about 252 (156)
Torsion-free abelian groups are Borel complete
Annals of MathematicsWe prove that the Borel space of torsion-free Abelian groups with domain $ω$ is Borel complete, i.e., the isomorphism relation on this Borel space is as complicated as possible, as an isomorphism relation. This solves a long-standing open problem in descriptive set theory, which dates back to the seminal paper on Borel reducibility of Friedman and ...
Saharon Shelah
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Localizations of torsion-free abelian groups II
Journal of Algebra, 2005 A homomorphism \(\alpha\colon A\to B\) between Abelian groups \(A,B\) is called a localization of \(A\) if every homomorphism \(\varphi\) from \(A\) to \(B\) has a unique extension to an endomorphism \(\psi\) of \(B\) in the sense that \(\varphi=\psi\circ\alpha\).
Manfred Dugas
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On Undecidability of Finite Subsets Theory for Torsion Abelian Groups
Mathematics, 2022 Let M be a commutative cancellative monoid with an element of infinite order. The binary operation can be extended to all finite subsets of M by the pointwise definition. So, we can consider the theory of finite subsets of M.
Sergey Mikhailovich Dudakov
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Regularity in torsion-free abelian groups [PDF]
Czechoslovak Mathematical Journal, 1992 Eine Untergruppe \(B\) einer torsionsfreien abelschen Gruppe \(A\) heißt regulär (kritisch regulär) falls \(t^ B(b) = t^ A(b)\) für alle \(b\in B\) (falls für alle Typen \(t\) gilt: \(B(t) \setminus B^*(t)_ * \subset A(t)\setminus A^*(t)_ *\)). Die Untergruppe \(B\) heißt stark regulär, falls \(B\) eine reguläre und eine kritisch reguläre Untergruppe ...
Müller, Edgar, Mutzbauer, Otto
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Torsion-free abelian groups revisited [PDF]
Rendiconti del Seminario Matematico della Università di Padova, 2020 Let G be a torsion-free abelian group of finite rank. The orbits of the action of Aut( G ) on the set of maximal independent subsets of
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On Some Results of a Torsion-Free Abelian Kernel Group
Recoletos Multidisciplinary Research Journal, 2014 In [6], for any torsion-free abelian groups Gand H, the kernel of Hin GisfHGGHHomfker, ker,. The kernel of Hin Gis a pure fully invariant subgroup of G.
Ricky B. Villeta
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On Some Results of a Torsion-Free Abelian Trace Group
Recoletos Multidisciplinary Research Journal, 2014 In [6], givenany torsion-free abelian groups Gand H, the pure trace of Hin Gis *,:,GHHomfHfGHtr which is equivalent to the set ZnGHHomfHfngGgsomefor ,,:.The pure trace GHtr, is a pure fully invariant subgroup of G.
Ricky B. Villeta
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A Distinguished Subgroup of Compact Abelian Groups
Axioms, 2022 Here “group” means additive abelian group. A compact group G contains δ–subgroups, that is, compact totally disconnected subgroups Δ such that G/Δ is a torus.
Dikran Dikranjan +3 more
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Discussiones Mathematicae - General Algebra and Applications, 2017 It is studied how rank two pure subgroups of a torsion-free Abelian group of rank three influences its structure and type set. In particular, the criterion for such a subgroup B to be a direct summand of a torsion-free Abelian group of rank three with ...
Najafizadeh Alireza, Woronowicz Mateusz
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Type II string theory on Calabi-Yau manifolds with torsion and non-Abelian discrete gauge symmetries
Journal of High Energy Physics, 2017 We provide the first explicit example of Type IIB string theory compactification on a globally defined Calabi-Yau threefold with torsion which results in a four-dimensional effective theory with a non-Abelian discrete gauge symmetry. Our example is based
Volker Braun +3 more
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