Gerbes, covariant derivatives, p-form lattice gauge theory, and the   Yang-Baxter equation
  In p-form lattice gauge theory, the fluctuating variables live on p-dimensional cells and interact around (p+1)-dimensional cells. It has been argued that the continuum version of this model should be described by (p-1)-gerbes. However, only connections and curvatures for gerbes are understood, not covariant derivatives. Using the lattice analogy, an alternative definition of gerbes is proposed: sections are functions phi(x,s), were x is the base point and s is the surface element. In this purely local formalism, there is a natural covariant derivative. The Yang-Baxter equation, and more generally the simplex equations, arise as zero-curvature conditions. The action of algebras of vector fields and gerbe gauge transformations, and their abelian extensions, are described. 
T. A. Larsson