Manindra Agrawal, Eric Allender, Samir Datta, Heribert Vollmer, Klaus W. Wagner

Motivated by the question of how to define an analog of interactive

proofs in the setting of logarithmic time- and space-bounded

computation, we study complexity classes defined in terms of

operators quantifying over oracles. We obtain new

characterizations of $\NCe$, $\L$, $\NL$, $\NP$, ...
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Nutan Limaye, Meena Mahajan, B. V. Raghavendra Rao

The parallel complexity class NC^1 has many equivalent models such as

polynomial size formulae and bounded width branching

programs. Caussinus et al. \cite{CMTV} considered arithmetizations of

two of these classes, #NC^1 and #BWBP. We further this study to

include arithmetization of other classes. In particular, we show that

counting paths ...
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Scott Aaronson, John Watrous

While closed timelike curves (CTCs) are not known to exist, studying their consequences has led to nontrivial insights in general relativity, quantum information, and other areas. In this paper we show that if CTCs existed, then quantum computers would be no more powerful than classical computers: both would have the ... more >>>

Raghav Kulkarni

The purpose of this paper is to study the deterministic

{\em isolation} for certain structures in directed and undirected

planar graphs.

The motivation behind this work is a recent development on this topic. For example, \cite{btv07} isolate a directed path in planar graphs and

\cite{dkr08} isolate a perfect matching in ...
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