Results 101 to 110 of about 1,625,403 (282)
, 2023 We introduce the theory of biset functors defined on finite categories. Previously, biset functors have been defined on groups, and in that context they are closely related to Mackey functors. Standard examples on groups include representation rings, the Burnside ring and group cohomology.
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, 2008 Plato's ideas and Aristotle's real types from the classical age, Nominalism and Realism of the mediaeval period and Whitehead's modern view of the world as pro- cess all come together in the formal representation by category theory of exactness in ...
Heather, Michael, Rossiter, Nick
core
Realization of spaces of commutative rings
Journal of the London Mathematical Society, Volume 111, Issue 5, May 2025.Abstract Motivated by recent work on the use of topological methods to study collections of rings between an integral domain and its quotient field, we examine spaces of subrings of a commutative ring, endowed with the Zariski or patch topologies. We introduce three notions to study such a space X$X$: patch bundles, patch presheaves and patch algebras.
Laura Cossu, Bruce Olberding
wiley +1 more source
Determinant functors on triangulated categories [PDF]
Journal of K-Theory, 2010 AbstractWe study determinant functors which are defined on a triangulated category and take values in a Picard category. The two main results are the existence of a universal determinant functor for every small triangulated category, and a comparison theorem for determinant functors on a triangulated category with a non-degenerate bounded t-structure ...
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A Zassenhaus Lemma for Digroups
MathematicsIn this paper, we construct a quotient structure on digroups. This construction yields a new functor from the category of digroups to the category of groups.
Guy Roger Biyogmam
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Witt vectors with coefficients and TR
Proceedings of the London Mathematical Society, Volume 130, Issue 5, May 2025.Abstract We give a new construction of p$p$‐typical Witt vectors with coefficients in terms of ghost maps and show that this construction is isomorphic to the one defined in terms of formal power series from the authors' previous paper. We show that our construction recovers Kaledin's polynomial Witt vectors in the case of vector spaces over a perfect ...
Emanuele Dotto +3 more
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From Morphism Categories to Functor Categories
Bulletin of the Malaysian Mathematical Sciences Society29 pages, an improved version of a paper with the same title, which was submitted ...
Hafezi, Rasool, Eshraghi, Hossein
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Adjoints, wrapping, and morphisms at infinity
Comptes Rendus. MathématiqueFor a localization of a smooth proper category along a subcategory preserved by the Serre functor, we show that morphisms in Efimov’s algebraizable categorical formal punctured neighborhood of infinity can be computed using the natural cone between right
Kuwagaki, Tatsuki, Shende, Vivek
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Functors on the category of finite sets [PDF]
Transactions of the American Mathematical Society, 1992 Given a covariant or contravariant functor from the category of finite sets to itself, one can define a function from natural numbers to natural numbers by seeing how the functor maps cardinalities. In this paper we answer the question: what numerical functions arise in this way from functors?
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Lattice of compactifications of a topological group [PDF]
Categories and General Algebraic Structures with Applications, 2019 We show that the lattice of compactifications of a topological group $G$ is a complete lattice which is isomorphic to the lattice of all closed normal subgroups of the Bohr compactification $bG$ of $G$.
Wei He, Zhiqiang Xiao
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