Unifying fundamental principle of H-duality

Identify a unifying fundamental principle that explains H-duality across algorithmic settings, reconciling the self-duality of residual norms in fixed-point algorithms developed in this work with the previously established duality between function values and gradient norms in smooth convex minimization.

Background

The paper establishes a new H-duality for fixed-point algorithms, showing that OHM and its dual share identical convergence rates with respect to the same residual measure, contrasting with prior convex minimization H-duality where function values are dual to gradient norms.

The authors emphasize that, despite superficial similarities, a single underlying principle connecting these dualities is currently unknown.

References

While the H-duality theory of this work and that of share some superficial similarities, the unifying fundamental principle remains unknown, and finding one is an interesting subject of future research.

Optimal Acceleration for Minimax and Fixed-Point Problems is Not Unique (2404.13228 - Yoon et al., 20 Apr 2024) in Section 5 (H-duality for fixed-point algorithms)