Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Internal monoid actions in a cartesian closed category and higher-dimensional group automorphisms

The notion of cat¹-group which was introduced by Loday is equivalent to the notions of crossed module and of internal category in the category of groups. This notion of cat¹-groups and their morphisms admits natural generalization to catⁿ-groups, which give rise to n-fold categories in the category...

Full description

Saved in:
Bibliographic Details
Main Author: Ramasu, Pako
Other Authors: Janelidze, George
Format: Thesis
Language:English
Published: Department of Mathematics and Applied Mathematics 2016
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613170836701184
access_status_str Open Access
author Ramasu, Pako
author2 Janelidze, George
author_browse Janelidze, George
Ramasu, Pako
author_facet Janelidze, George
Ramasu, Pako
author_sort Ramasu, Pako
collection Thesis
description The notion of cat¹-group which was introduced by Loday is equivalent to the notions of crossed module and of internal category in the category of groups. This notion of cat¹-groups and their morphisms admits natural generalization to catⁿ-groups, which give rise to n-fold categories in the category of groups. There is also a characterization of catⁿ-groups in terms of crossed n-cubes which was given by Ellis and Steiner. The category Catⁿ (Groups) of internal n-fold categories in the category of groups is a cartesian closed category, however given an object X in Catⁿ (Groups), calculating corresponding action representing object Aut (X) directly would require an enormous calculations. The main purpose of the thesis is to describe that object avoiding such calculations as much as possible. The main tool used in the thesis, apart from the theory of cartesian closed categories, is Loday's theory of catⁿ-groups. We de ne a catⁿ-group X as an additive Mₙ-group X , and then construct the corresponding Aut (X), where Mₙ is a monoid. Since the category of catⁿ-groups is equivalent to Catⁿ (Groups) and since the cartesian closed category Sets Mₙ of Mₙ-sets is much easier to handle than the cartesian closed category of n-fold categories, we shall work just with catⁿ-groups. To assert that, Aut (X) is an action representing object in Sets Mₙ , is to as- sert that, there is a canonical bijection between B-actions of catⁿ-group B on X and the internal group homomorphism B --> Aut (X). Thus, we confirm the construction of Aut (X) by establishing that bijection. Finally, as one of the results of this work, we give the comparison between our cat¹-group Aut (X) and Norrie's actor crossed module (D (G;Z) ;Aut (Z;G;p) w) of a crossed module (Z;G;p) in dimension one.
format Thesis
id oai:open.uct.ac.za:11427/20248
institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:31:53.390Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2016
publishDateRange 2016
publishDateSort 2016
publisher Department of Mathematics and Applied Mathematics
publisherStr Department of Mathematics and Applied Mathematics
record_format dspace
source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/20248 Internal monoid actions in a cartesian closed category and higher-dimensional group automorphisms Ramasu, Pako Janelidze, George Mathematics The notion of cat¹-group which was introduced by Loday is equivalent to the notions of crossed module and of internal category in the category of groups. This notion of cat¹-groups and their morphisms admits natural generalization to catⁿ-groups, which give rise to n-fold categories in the category of groups. There is also a characterization of catⁿ-groups in terms of crossed n-cubes which was given by Ellis and Steiner. The category Catⁿ (Groups) of internal n-fold categories in the category of groups is a cartesian closed category, however given an object X in Catⁿ (Groups), calculating corresponding action representing object Aut (X) directly would require an enormous calculations. The main purpose of the thesis is to describe that object avoiding such calculations as much as possible. The main tool used in the thesis, apart from the theory of cartesian closed categories, is Loday's theory of catⁿ-groups. We de ne a catⁿ-group X as an additive Mₙ-group X , and then construct the corresponding Aut (X), where Mₙ is a monoid. Since the category of catⁿ-groups is equivalent to Catⁿ (Groups) and since the cartesian closed category Sets Mₙ of Mₙ-sets is much easier to handle than the cartesian closed category of n-fold categories, we shall work just with catⁿ-groups. To assert that, Aut (X) is an action representing object in Sets Mₙ , is to as- sert that, there is a canonical bijection between B-actions of catⁿ-group B on X and the internal group homomorphism B --> Aut (X). Thus, we confirm the construction of Aut (X) by establishing that bijection. Finally, as one of the results of this work, we give the comparison between our cat¹-group Aut (X) and Norrie's actor crossed module (D (G;Z) ;Aut (Z;G;p) w) of a crossed module (Z;G;p) in dimension one. 2016-07-07T09:52:07Z 2016-07-07T09:52:07Z 2015 Doctoral Thesis Doctoral PhD http://hdl.handle.net/11427/20248 eng application/pdf Department of Mathematics and Applied Mathematics Faculty of Science University of Cape Town
spellingShingle Mathematics
Ramasu, Pako
Internal monoid actions in a cartesian closed category and higher-dimensional group automorphisms
thesis_degree_str Doctoral
title Internal monoid actions in a cartesian closed category and higher-dimensional group automorphisms
title_full Internal monoid actions in a cartesian closed category and higher-dimensional group automorphisms
title_fullStr Internal monoid actions in a cartesian closed category and higher-dimensional group automorphisms
title_full_unstemmed Internal monoid actions in a cartesian closed category and higher-dimensional group automorphisms
title_short Internal monoid actions in a cartesian closed category and higher-dimensional group automorphisms
title_sort internal monoid actions in a cartesian closed category and higher dimensional group automorphisms
topic Mathematics
url http://hdl.handle.net/11427/20248
work_keys_str_mv AT ramasupako internalmonoidactionsinacartesianclosedcategoryandhigherdimensionalgroupautomorphisms