nLab p1-structure

Idea

c-structure for $c$ the 1st Pontryagin class $p_1$, o.e. trivialization of $p_1$.

In the presence of Spin structure then $p_1$-structure is also called string structure. In the presence of (just) orientation (i.e. w1-structure?) on 3-manifolds then $p_1$-structure is closely related to Atiyah 2-framing structure.