25 research outputs found
Coproducts and decomposable machines
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
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
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
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
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
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
This is the first draft of a book about higher categories approached by
iterating Segal's method, as in Tamsamani's definition of -nerve and
Pelissier's thesis. If is a tractable left proper cartesian model category,
we construct a tractable left proper cartesian model structure on the category
of -precategories. The procedure can then be iterated, leading to model
categories of -categories