On the complexity of deciding connectedness and computing Betti numbers of a complex algebraic variety
نویسنده
چکیده
We extend the lower bounds on the complexity of computing Betti numbers proved in [6] to complex algebraic varieties. More precisely, we first prove that the problem of deciding connectedness of a complex affine or projective variety given as the zero set of integer polynomials is PSPACE-hard. Then we prove PSPACE-hardness for the more general problem of deciding whether the Betti number of fixed order of a complex affine or projective variety is at most some given integer.
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ورودعنوان ژورنال:
- J. Complexity
دوره 23 شماره
صفحات -
تاریخ انتشار 2007