Singularity Exchange at the Frontier of the Space

  • Dirk Siersma
  • Mihai Tibăr
Conference paper
Part of the Trends in Mathematics book series (TM)


In deformations of polynomial functions one may encounter “singularity exchange at infinity” when singular points disappear from the space and produce “virtual” singularities which have an influence on the topology of the limit polynomial. We find several rules of this exchange phenomenon, in which the total quantity of singularity turns out to be not conserved in general.


Deformation of polynomials singularities at infinity non-conservation of number of vanishing cycles 


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Copyright information

© Birkhäuser Verlag Basel/Switzerland 2006

Authors and Affiliations

  • Dirk Siersma
    • 1
  • Mihai Tibăr
    • 2
  1. 1.Mathematisch InstituutUniversiteit UtrechtUtrechtThe Netherlands
  2. 2.MathématiquesUniversité des Sciences et Technologies de LilleVilleneuve d’AscqFrance

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