Smooth, nonsymplectic embeddings of rational balls in the complex projective plane
arXiv:1906.05913
Abstract
We exhibit an infinite family of rational homology balls which embed smoothly but not symplectically in the complex projective plane. We also obtain a new lattice embedding obstruction from Donaldson's diagonalisation theorem, and use this to show that no two of our examples may be embedded disjointly.
12 pages, 3 figures. Final version, accepted for publication in Q. J. Math