# THE SYMPLECTIC TOPOLOGY OF RAMANUJAM'S SURFACE

```@article{Seidel2004THEST,
title={THE SYMPLECTIC TOPOLOGY OF RAMANUJAM'S SURFACE},
author={Paul Seidel and Ivan Smith},
journal={Commentarii Mathematici Helvetici},
year={2004},
volume={80},
pages={859-881}
}```
• Published 26 November 2004
• Mathematics
• Commentarii Mathematici Helvetici
Ramanujam's surface \$M\$ is a contractible affine algebraic surface which is not homeomorphic to the affine plane. For any \$m>1\$ the product \$M^m\$ is diffeomorphic to Euclidean space \${mathbb R}^{4m}\$. We show that, for every \$m>0\$, \$M^m\$ cannot be symplectically embedded into a subcritical Stein manifold. This gives the first examples of exotic symplectic structures on Euclidean space which are convex at infinity. It follows that any exhausting plurisubharmonic Morse function on \$M^m\$ has at…
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