Abstract
We show that, for hypersurface sections (in the sense of Damon) of isolated functions singularities, the Tjurina and Milnor numbers coincide. An application of this to the families of 2 × 2 symmetric and arbitrary matrices proves the conjectures naturally arising from the results of [2] and [3]. In addition, we study the vanishing homology of the determinantal curves of two-parameter families of symmetric order 2 matrices and construct Dynkin diagrams of simple singularities of such families.
Supported by INTAS-00259, NWO047008005 and RBRF99010147 research grants
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Bruce, J.W., Goryunov, V.V., Zakalyukin, V.M. (2002). Sectional Singularities and Geometry of Families of Planar Quadratic Forms. In: Libgober, A., Tibăr, M. (eds) Trends in Singularities. Trends in Mathematics. Birkhäuser, Basel. https://doi.org/10.1007/978-3-0348-8161-6_3
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DOI: https://doi.org/10.1007/978-3-0348-8161-6_3
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