Links of rational singularities, L-spaces and LO fundamental groups

András Némethi

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arXiv · 1510.07128

Links of rational singularities, L-spaces and LO fundamental groups

András Némethi

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Abstract

We prove that the link of a complex normal surface singularity is an L--space if and only if the singularity is rational. This via a recent result of Hanselman, J. Rasmussen, S. D. Rasmussen and Watson (proving the conjecture of Boyer, Gordon and Watson), shows that a singularity link is not rational if and only if its fundamental group is left-orderable if and only if it admits a coorientable taut foliation.

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András Némethi. 2015-10-24. Links of rational singularities, L-spaces and LO fundamental groups. https://arxiv.org/abs/1510.07128

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