We define Concurrent Turing Machines (CTMs) as Turing machines with Petri nets as finite control. This leads to machines with arbitrary many tape heads, thus subsuming any class ...
Abstract. Turing machines exposed to a small stochastic noise are considered. An exact characterisation of their (≈ Π0 2 ) computational power (as noise level tends to 0) is obt...
Unambiguity in alternating Turing machines has received considerable attention in the context of analyzing globally-unique games by Aida et al. [ACRW04] and in the design of effic...
This paper shows that satisfiability for Propositional Dynamic Logic with Intersection is EXPSPACE-hard. The proof uses a reduction from the word problem for alternating, exponent...