Collapsing Exact Arithmetic Hierarchies
نویسندگان
چکیده
We provide a uniform framework for proving the collapse of the hierarchy NC(C) for an exact arithmetic class C of polynomial degree. These hierarchies collapse all the way down to the third level of the AC-hierarchy, AC3(C). Our main collapsing exhibits are the classes C ∈ {C=NC,C=L,C=SAC,C=P}. NC(C=L) and NC(C=P) are already known to collapse [1,18,19]. We reiterate that our contribution is a framework that works for all these hierarchies. Our proof generalizes a proof from [8] where it is used to prove the collapse of the AC(C=NC) hierarchy. It is essentially based on a polynomial degree characterization of each of the base classes.
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عنوان ژورنال:
- Electronic Colloquium on Computational Complexity (ECCC)
دوره 20 شماره
صفحات -
تاریخ انتشار 2013