English

Lower bounds on the size of semi-quantum finite automata

Formal Languages and Automata Theory 2015-10-06 v2 Quantum Physics

Abstract

In the literature, there exist several interesting hybrid models of finite automata which have both quantum and classical states. We call them semi-quantum automata. In this paper, we compare the descriptional power of these models with that of DFA. Specifically, we present a uniform method that gives a lower bound on the size of the three existing main models of semi-quantum automata, and this bound shows that semi-quantum automata can be at most exponentially more concise than DFA. Compared with a recent work (Bianchi, Mereghetti, Palano, Theoret. Comput. Sci., 551(2014), 102-115), our method shows the following two advantages: (i) our method is much more concise; and (ii) our method is universal, since it is applicable to the three existing main models of semi-quantum automata, instead of only a specific model.

Keywords

Cite

@article{arxiv.1502.02839,
  title  = {Lower bounds on the size of semi-quantum finite automata},
  author = {Lvzhou Li and Daowen Qiu},
  journal= {arXiv preprint arXiv:1502.02839},
  year   = {2015}
}

Comments

arXiv admin note: text overlap with arXiv:1206.2131. To appear in Theoretical Computer Science