Spahn univalence in simplicial sets

1. Representability of fibrations

Let XX be a simplicial set, let . W α(X)W_\alpha(X) denote the class of well ordered morphisms f:YXf:Y\to X. Then the assignation XW αXX\mapsto W_\alpha_X is a functor which is representable by the functor y opy op:Δ opSety^{op}\circ y^{op}:\Delta^{op}\to Set where yy is Yoneda (…)

References

For a different model of the univalence axiom:

For universes:

For references and recent contributions on cordials: