“…Starting with [23] this observation underpinned new interplay between Skorokhod embeddings and robust finance, e.g., [12,15], and subsequently led to the introduction of martingale optimal transport in [7,18] and the ensuing rapid and rich growth of this field. More recently, optimal transport techniques have also been used as means for non-parametric calibration: OT is used as a means to project one's favourite model onto the set of calibrated martingales, i.e., martingales which satisfy a set of given distributional constraints, see [21,22]. In general, this OT-calibration problem is solved via its dual, numerically optimizing over solutions to a nonlinear PDE, which can be challenging.…”