Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

We build a model structure from the simple point of departure of a structured interval in a monoidal category — more generally, a structured cylinder and a structured co-cylinder in a category.

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (p. 79-80).

A fully extended framed topological field theory with target in a symmetric monoidal n-catgeory C is a symmetric monoidal functor Z from Bord(n) to C, where Bord(n) is the symmetric monoidal n-category of n-framed bordisms. The cobordism hypothesis says that such field theories are classified by fully dualizable objects in C. Given a fully dualizable object X in C, we are interested in computing the values of the corresponding field theory on specific framed bordisms. This leads to the question of finding a presentation for Bord(n). In view of the cobordism hypothesis, this can be rephrased in terms of finding coherence data for fully dualizable objects in a symmetric monoidal n-category. We prove a characterization of full dualizability of an object X in terms of existence of a dual of X and existence of adjoints for a finite number of higher morphisms. This reduces the problem of finding coherence data for fully dualizable objects to that of finding coherence data for duals and adjoints. For n=3, and in the setting of strict symmetric monoidal 3-categories, we find this coherence data, and we prove the corresponding coherence theorems. The proofs rely on extensive use of a graphical calculus for strict monoidal 3-categories.

O ponto central dessa dissertação é expor categorialmente as funções de verdade do cálculo proposicional clássico, assim como provar, também categorialmente, que a definição dada se comporta tal como as tabelas de verdade dos operadores. Para tanto é feita uma exposição axiomática de teoria de categorias, salientando as construções e conceitos que servirão para o propósito principal da dissertação. É dada uma maior atenção ao conceito de Topos, estrutura onde as funções de verdade são em princípio construídas. Tal exposição é precedida de uma breve exposição da história de teoria de categorias. Por fim é apresentada uma possível nova estrutra, mais simples que Topos, onde também se constrói as funções de verdade. / The main purpose of this dissertation is to give a categorial account of the truth functions from the classic propositional calculus, as well as to prove, also categorially, that the definition given behave as the truth tables of the operators. For this end, an axiomatic exposition of category theory is made, focusing on constructions and concepts which will be used for the main purpose of the dissertation. More attention is given to the concept of Topos, structure where the truth functions are primarily constructed. Preceded by a brief exposition of Category Theory history. At the end, a new possible structure in which truth functions may be constructed, simpler than a Topos, is presented.

The main goal of this thesis is to construct a tensor product on the 2-category BFC-A of braided fusion categories containing a symmetric fusion category A. We achieve this by introducing the new notion of Z(A)-crossed braided categories. These are categories enriched over the Drinfeld centre Z(A) of the symmetric fusion category. We show that Z(A) admits an additional symmetric tensor structure, which makes it into a 2-fold monoidal category. ByTannaka duality, A= Rep(G) (or Rep(G; w)) for a finite group G (or finite super-group (G,w)). Under this identication Z(A) = VectG[G], the category of G-equivariant vector bundles over G, and we show that the symmetric tensor product corresponds to (a super version of) to the brewise tensor product. We use the additional symmetric tensor product on Z(A) to define the composition in Z(A)-crossed braided categories, whereas the usual tensor product is used for the monoidal structure. We further require this monoidal structure to be braided for the switch map that uses the braiding in Z(A). We show that the 2-category Z(A)-XBF is equivalent to both BFC=A and the 2-category of (super)-G-crossed braided categories. Using the former equivalence, the reduced tensor product on BFC-A is dened in terms of the enriched Cartesian product of Z(A)-enriched categories on Z(A)-XBF. The reduced tensor product obtained in this way has as unit Z(A). It induces a pairing between minimal modular extensions of categories having A as their Mueger centre.