Generalised Thurston-bennequin Invariants for Real Algebraic Surface Singularities

نویسنده

  • FERİT ÖZTÜRK
چکیده

A generalised Thurston-Bennequin invariant for a Q-singularity of a real algebraic variety is defined as a linking form on the homologies of the real link of the singularity. The main goal of this paper is to present a method to calculate the linking form in terms of the very good resolution graph of a real normal unibranch singularity of a real algebraic surface. For such singularities, the value of the linking form is the Thurston-Bennequin number of the real link of the singularity. As a special case of unibranch surface singularities, the behaviour of the linking form is investigated on the Brieskorn double points xm + yn ± z = 0.

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تاریخ انتشار 2002