Meaning
The relative center class records the failure of a marked external
For a meridional cocycle
The homotopy fiber is doing real work. Its two coordinates distinguish a refinement representative from the admissible correction needed to compare that representative with ordinary filling data. The zero in the first coordinate says that no new bulk refinement class is being inserted. The second coordinate records the collar datum that ordinary admissibility would have to absorb.
So
Example (illustrative)
Walk once around a collar meridian linking an external source. If the normalized cocycle evaluates to
Scope and limits
The class labels a topological obstruction. It does not itself provide a positive operator, a frame inequality, an energy density, or a string. Those require later represented analytic constructions.
Source
Phenomenological Implications I, §3.1, Definition 3.1 and Proposition 3.2.