Extend the P=W correspondence to irregular Hitchin systems

Prove that the perverse filtration on the cohomology of type-$A$ wild Hitchin moduli spaces with irregular singularities agrees with the weight filtration of the corresponding mixed Hodge structure on the character variety, thereby extending the $P=W$ conjecture from the regular-singular case to the irregular case.

Background

The paper studies type-An1A_{n-1} Hitchin moduli spaces on the projective line with one irregular and one regular singularity. It defines two candidate gradings on cohomology: the perverse filtration induced by the Hitchin fibration and the weight filtration of the mixed Hodge structure obtained by viewing the moduli space as a character variety.

For regular singularities, the P=WP=W conjecture predicts an equivalence between these filtrations. The paper explicitly proposes that this equivalence should continue to hold for the wild, irregular systems considered here, but does not establish it.

References

The celebrated $P=W$ conjecture posits the equivalence of these filtrations for the $A$ type case with regular singularities, and we conjecture it is extended to the irregular case.

Bigraded Polynomials for the Cohomology of Wild Hitchin Systems  (2509.20872 - Xie, 25 Sep 2025) in Section 1, Introduction