Topological triviality of versal unfoldings of complete intersections

James Damon

Annales de l'institut Fourier (1984)

  • Volume: 34, Issue: 4, page 225-251
  • ISSN: 0373-0956

Abstract

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We obtain algebraic and geometric conditions for the topological triviality of versal unfoldings of weighted homogeneous complete intersections along subspaces corresponding to deformations of maximal weight. These results are applied: to infinite families of surface singularities in C 4 which begin with the exceptional unimodular singularities, to the intersection of pairs of generic quadrics, and to certain curve singularities.The algebraic conditions are related to the operation of adjoining powers, a generalization for complete intersections of a special form of the Thom-Sebastiani operation. A duality result is proven which relates the Jacobian algebra of f being Gorenstein with N ˜ ( F ) * being principal, i.e. generated by one element (here F is obtained from f by adjoining powers, and N ˜ ( F ) * is the dual of the space of non-trivial infinitesimal deformations.

How to cite

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Damon, James. "Topological triviality of versal unfoldings of complete intersections." Annales de l'institut Fourier 34.4 (1984): 225-251. <http://eudml.org/doc/74657>.

@article{Damon1984,
abstract = {We obtain algebraic and geometric conditions for the topological triviality of versal unfoldings of weighted homogeneous complete intersections along subspaces corresponding to deformations of maximal weight. These results are applied: to infinite families of surface singularities in $C^4$ which begin with the exceptional unimodular singularities, to the intersection of pairs of generic quadrics, and to certain curve singularities.The algebraic conditions are related to the operation of adjoining powers, a generalization for complete intersections of a special form of the Thom-Sebastiani operation. A duality result is proven which relates the Jacobian algebra of $f$ being Gorenstein with $\widetilde\{N\}(F)^*$ being principal, i.e. generated by one element (here $F$ is obtained from $f$ by adjoining powers, and $\widetilde\{N\}(F)^*$ is the dual of the space of non-trivial infinitesimal deformations.},
author = {Damon, James},
journal = {Annales de l'institut Fourier},
keywords = {exceptional unimodular singularities; Thom-Sebastiani operation; Jacobian algebra},
language = {eng},
number = {4},
pages = {225-251},
publisher = {Association des Annales de l'Institut Fourier},
title = {Topological triviality of versal unfoldings of complete intersections},
url = {http://eudml.org/doc/74657},
volume = {34},
year = {1984},
}

TY - JOUR
AU - Damon, James
TI - Topological triviality of versal unfoldings of complete intersections
JO - Annales de l'institut Fourier
PY - 1984
PB - Association des Annales de l'Institut Fourier
VL - 34
IS - 4
SP - 225
EP - 251
AB - We obtain algebraic and geometric conditions for the topological triviality of versal unfoldings of weighted homogeneous complete intersections along subspaces corresponding to deformations of maximal weight. These results are applied: to infinite families of surface singularities in $C^4$ which begin with the exceptional unimodular singularities, to the intersection of pairs of generic quadrics, and to certain curve singularities.The algebraic conditions are related to the operation of adjoining powers, a generalization for complete intersections of a special form of the Thom-Sebastiani operation. A duality result is proven which relates the Jacobian algebra of $f$ being Gorenstein with $\widetilde{N}(F)^*$ being principal, i.e. generated by one element (here $F$ is obtained from $f$ by adjoining powers, and $\widetilde{N}(F)^*$ is the dual of the space of non-trivial infinitesimal deformations.
LA - eng
KW - exceptional unimodular singularities; Thom-Sebastiani operation; Jacobian algebra
UR - http://eudml.org/doc/74657
ER -

References

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