C.A. Giller defined a crossing change for surfaces in $4$-space,
and proved an unknotting theorem. In this paper, we present
such an unknotting theorem for singular surface braids, extending
S. Kamada's result for those without branch points. As a consequence,
we recover Giller's unknotting theorem. We also study finite
type invariants for singular surface braids associated with
the crossing changes.
References
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Mathematical Reviews (MathSciNet):
MR674227
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Mathematical Reviews (MathSciNet):
MR699004
O.Ya. Viro: Lecture given at Osaka City University, September, 1990.
