text/definitions.tex
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     1 %!TEX root = ../blob1.tex
     1 %!TEX root = ../blob1.tex
     2 
     2 
     3 \section{Definitions}
     3 \section{Definitions}
     4 \label{sec:definitions}
     4 \label{sec:definitions}
       
     5 
       
     6 \nn{this section is a bit out of date; needs to be updated 
       
     7 to fit with $n$-category definition given later}
     5 
     8 
     6 \subsection{Systems of fields}
     9 \subsection{Systems of fields}
     7 \label{sec:fields}
    10 \label{sec:fields}
     8 
    11 
     9 Let $\cM_k$ denote the category (groupoid, in fact) with objects 
    12 Let $\cM_k$ denote the category (groupoid, in fact) with objects 
    17 
    20 
    18 A $n$-dimensional {\it system of fields} in $\cS$
    21 A $n$-dimensional {\it system of fields} in $\cS$
    19 is a collection of functors $\cC_k : \cM_k \to \Set$ for $0 \leq k \leq n$
    22 is a collection of functors $\cC_k : \cM_k \to \Set$ for $0 \leq k \leq n$
    20 together with some additional data and satisfying some additional conditions, all specified below.
    23 together with some additional data and satisfying some additional conditions, all specified below.
    21 
    24 
    22 \nn{refer somewhere to my TQFT notes \cite{kw:tqft}, and possibly also to paper with Chris}
    25 \nn{refer somewhere to my TQFT notes \cite{kw:tqft}}
    23 
    26 
    24 Before finishing the definition of fields, we give two motivating examples
    27 Before finishing the definition of fields, we give two motivating examples
    25 (actually, families of examples) of systems of fields.
    28 (actually, families of examples) of systems of fields.
    26 
    29 
    27 The first examples: Fix a target space $B$, and let $\cC(X)$ be the set of continuous maps
    30 The first examples: Fix a target space $B$, and let $\cC(X)$ be the set of continuous maps