Intrinsic Mirror Symmetry
Mark Gross, Bernd Siebert
TL;DR
This work constructs an intrinsic mirror ring for a log Calabi–Yau pair (X,D) or a maximally unipotent degeneration X→B by counting punctured Gromov–Witten invariants N^A_{pqr} via tropicalization data. The central object R is built from the tropical lattice on the dual intersection complex with multiplication governed by these invariants, yielding Spec R (or Proj R) as a mirror to X∖D in the log Calabi–Yau case (and to the degeneration in the relative case). A key achievement is proving associativity of the resulting product under two broad nef/CY-type conditions, using a logarithmic WDVV-style argument that harnesses tropical geometry, transversality, and a refined gluing theory for punctured maps. The paper also develops the invariant construction and shows that the resulting mirror data is robust under compactification changes, connecting to symplectic cohomology and providing a flexible framework for relative quantum-like structures. Overall, it advances a general algebro-geometric realization of mirror symmetry via punctured invariants, tropical methods, and log-geometry, with broad potential for computation and applications in higher dimensions.
Abstract
We associate a ring R to a log Calabi-Yau pair (X,D) or a degeneration of Calabi-Yau manifolds X->B. The vector space underlying R is determined by the tropicalization of (X,D) or X->B, while the product rule is defined using punctured Gromov-Witten invariants, defined in joint work with Abramovich and Chen. In the log Calabi-Yau case, if D is maximally degenerate, then we propose that Spec R is the mirror to X\D, while in the Calabi-Yau degeneration case, if the degeneration is maximally unipotent, the mirror is expected to be Proj R. The main result in this paper is that R as defined is an associative, commutative ring with unit, with associativity the most difficult part.
