25 research outputs found

    Coproducts and decomposable machines

    Get PDF
    The crucial discovery reported here is that the free monoid U* on the input set U does not yield a sufficiently rich set of inputs when algebraic structure is placed on the machine. For group machines, the appropriate structure is the coproduct U§ of an infinite sequence of copies of U. U§ reduces to a reasonable facsimile of U* in the Abelian case. A structure theorem for monoids of linear systems reveals the R monoid of Give'on and Zalcstein as appropriate only when no distinct powers of the statetransition matrix have the same action

    Ext in the nineties

    Get PDF
    We describe a package of programs to calculate minimal resolutions, chain maps, and null homotopies in the category of modules over a connected algebra overe Z_2 and in the category of unstable modules over the mod 2 Steenrod algebra. They are available for free distribution and intended for use as an Adams spectral sequence \u27pocket calculator\u27. We provide a sample of the results obtained from them

    Homology and Cohomology of E-infinity Ring Spectra

    Full text link
    Every homology or cohomology theory on a category of E-infinity ring spectra is Topological Andre-Quillen homology or cohomology with appropriate coefficients. Analogous results hold for the category of A-infinity ring spectra and for categories of algebras over many other operads

    量子写像における正値性と完全正値性の差異

    Get PDF
    学位の種別: 課程博士審査委員会委員 : (主査)東京大学准教授 筒井 泉, 国立情報学研究所准教授 蓮尾 一郎, 東京大学教授 緒方 芳子, 東京大学准教授 藤堂 真治, 東京大学教授 勝本 信吾University of Tokyo(東京大学

    Structured Decompositions: Structural and Algorithmic Compositionality

    Full text link
    We introduce structured decompositions: category-theoretic generalizations of many combinatorial invariants -- including tree-width, layered tree-width, co-tree-width and graph decomposition width -- which have played a central role in the study of structural and algorithmic compositionality in both graph theory and parameterized complexity. Structured decompositions allow us to generalize combinatorial invariants to new settings (for example decompositions of matroids) in which they describe algorithmically useful structural compositionality. As an application of our theory we prove an algorithmic meta theorem for the Sub_P-composition problem which, when instantiated in the category of graphs, yields compositional algorithms for NP-hard problems such as: Maximum Bipartite Subgraph, Maximum Planar Subgraph and Longest Path

    The Quantum Monadology

    Full text link
    The modern theory of functional programming languages uses monads for encoding computational side-effects and side-contexts, beyond bare-bone program logic. Even though quantum computing is intrinsically side-effectful (as in quantum measurement) and context-dependent (as on mixed ancillary states), little of this monadic paradigm has previously been brought to bear on quantum programming languages. Here we systematically analyze the (co)monads on categories of parameterized module spectra which are induced by Grothendieck's "motivic yoga of operations" -- for the present purpose specialized to HC-modules and further to set-indexed complex vector spaces. Interpreting an indexed vector space as a collection of alternative possible quantum state spaces parameterized by quantum measurement results, as familiar from Proto-Quipper-semantics, we find that these (co)monads provide a comprehensive natural language for functional quantum programming with classical control and with "dynamic lifting" of quantum measurement results back into classical contexts. We close by indicating a domain-specific quantum programming language (QS) expressing these monadic quantum effects in transparent do-notation, embeddable into the recently constructed Linear Homotopy Type Theory (LHoTT) which interprets into parameterized module spectra. Once embedded into LHoTT, this should make for formally verifiable universal quantum programming with linear quantum types, classical control, dynamic lifting, and notably also with topological effects.Comment: 120 pages, various figure

    Homotopy theory of higher categories

    Full text link
    This is the first draft of a book about higher categories approached by iterating Segal's method, as in Tamsamani's definition of nn-nerve and Pelissier's thesis. If MM is a tractable left proper cartesian model category, we construct a tractable left proper cartesian model structure on the category of MM-precategories. The procedure can then be iterated, leading to model categories of (,n)(\infty, n)-categories
    corecore