Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Structures and Diagrammatics of Four Dimensional Topological Lattice
  Field Theories   Crane and Frenkel proposed a state sum invariant for triangulated
4-manifolds.They defined and used new algebraic structures called Hopf
categories for their construction. Crane and Yetter studied Hopf categories and
gave some examples using group cocycles that are associated to the Drinfeld
double of a finite group.
  In this paper we define a state sum invariant of triangulated 4-manifolds
using Crane-Yetter cocycles as Boltzmann weights. Our invariant generalizes the
3-dimensional invariants defined by Dijkgraaf and Witten and the invariants
that are defined via Hopf algebras. We present diagrammatic methods for the
study of such invariants that illustrate connections between Hopf categories
and moves to triangulations.

14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
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The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ