Euclidean 4-simplices and invariants of four-dimensional manifolds: II.   An algebraic complex and moves 2 <-> 4
  We write out some sequences of linear maps of vector spaces with fixed bases. Each term of a sequence is a linear space of differentials of metric values ascribed to the elements of a simplicial complex - a triangulation of a manifold. If the sequence turns out to be an acyclic complex then one can construct a manifold invariant out of its torsion. We demonstrate this first for three-dimensional manifolds, and then we conduct the part, related to moves 2 <-> 4, of the corresponding work for four-dimensional manifolds. 
Igor G. Korepanov