Abstract
We construct potentially new manifolds homeomorphic but not diffeomorphic to \(\mathbb{CP}^{2} \) # \(8\overline{{\mathbb{CP}}^{2}}\) and \(\mathbb{CP}^{2}\)# \(9\overline{{\mathbb{CP}}^{2}}\) via rational blowdown surgery along certain 4-valent plumbing graphs. This way all the graph classes from [5] have a representative which admits a rational blowdown leading to an exotic manifold. We emphasize the simplicity of the constructions which boils down to finding a good configuration of complex lines and quadrics in \(\mathbb{CP}^{2}\), and deciding which intersections to blow up.
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Acknowledgements
I would like to thank my advisor András Stipsicz for introducing me to smooth 4-dimensional topology, pointing me to the problems discussed in this paper, and selflessly guiding me through my PhD journey.
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Mihajlović, S. Small exotic \(4\)-manifolds from lines and quadrics in \(\mathbb{CP}^{2}\). Acta Math. Hungar. 162, 584–603 (2020). https://doi.org/10.1007/s10474-020-01088-5
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DOI: https://doi.org/10.1007/s10474-020-01088-5