6 research outputs found
Representing a P-complete problem by small trellis automata
A restricted case of the Circuit Value Problem known as the Sequential NOR
Circuit Value Problem was recently used to obtain very succinct examples of
conjunctive grammars, Boolean grammars and language equations representing
P-complete languages (Okhotin, http://dx.doi.org/10.1007/978-3-540-74593-8_23
"A simple P-complete problem and its representations by language equations",
MCU 2007). In this paper, a new encoding of the same problem is proposed, and a
trellis automaton (one-way real-time cellular automaton) with 11 states solving
this problem is constructed
On the equivalence of linear conjunctive grammars and trellis automata
This paper establishes computational equivalence of two seemingly unrelated concepts:
linear conjunctive grammars and trellis automata.
Trellis automata, also studied under the name of one-way real-time cellular automata,
have been known since early 1980s as a purely abstract model of parallel computers, while
linear conjunctive grammars, introduced a few years ago, are linear context-free grammars extended
with an explicit intersection operation.
Their equivalence implies the equivalence of several other formal systems,
including a certain restricted class of Turing machines and a certain type of language equations, thus
giving further evidence for the importance of the language family they all generate