Giovanni Pighizzini

Last updated
Giovanni Pighizzini
Alma mater University of Milan
Known for state complexity
Scientific career
Fields Theoretical Computer Science
formal language theory
Institutions University of Milan

Giovanni Pighizzini is an Italian theoretical computer scientist known for his work in formal language theory and particularly in state complexity of two-way finite automata. He earned his PhD in 1993 from the University of Milan, where he is a full professor since 2001. Pighizzini serves as the Steering Committee Chair of the annual Descriptional Complexity of Formal Systems academic conference since 2006.

Contents

Research contributions

Pighizzini obtained optimal state complexity tradeoffs between different types of finite automata over a one-letter alphabet, [1] [2] [3] In particular, in his joint paper with Geffert and Mereghetti [2] he presented the first simulation of two-way nondeterministic finite automata by two-way deterministic finite automata using Savitch's theorem, contributing to the 2DFA vs. 2NFA open question. Jointly with Jirásková, he determined state complexity of self-verifying finite automata. [4]

He also contributed to the computational complexity theory by results on sublogarithmic space complexity classes [5] and on the complexity of searching for a lexicographically maximal string. [6]

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References

  1. Mereghetti, Carlo; Pighizzini, Giovanni (2001). "Optimal Simulations between Unary Automata". SIAM Journal on Computing. 30 (6): 1976–1992. doi:10.1137/S009753979935431X. hdl: 2434/35121 . ISSN   0097-5397.
  2. 1 2 Geffert, Viliam; Mereghetti, Carlo; Pighizzini, Giovanni (2003). "Converting two-way nondeterministic unary automata into simpler automata". Theoretical Computer Science. 295 (1–3): 189–203. doi:10.1016/S0304-3975(02)00403-6. ISSN   0304-3975.
  3. Geffert, Viliam; Guillon, Bruno; Pighizzini, Giovanni (2014). "Two-way automata making choices only at the endmarkers". Information and Computation. 239: 71–86. arXiv: 1110.1263 . doi:10.1016/j.ic.2014.08.009. ISSN   0890-5401.
  4. Jirásková, Galina; Pighizzini, Giovanni (2011). "Optimal simulation of self-verifying automata by deterministic automata". Information and Computation. 209 (3): 528–535. doi:10.1016/j.ic.2010.11.017. ISSN   0890-5401.
  5. Geffert, Viliam; Mereghetti, Carlo; Pighizzini, Giovanni (1998). "Sublogarithmic Bounds on Space and Reversals". SIAM Journal on Computing. 28 (1): 325–340. doi:10.1137/S0097539796301306. hdl: 2434/178756 . ISSN   0097-5397. S2CID   37853723.
  6. Allender, Eric; Bruschi, Danilo; Pighizzini, Giovanni (1993). "The complexity of computing maximal word functions". Computational Complexity. 3 (4): 368–391. doi:10.1007/BF01275489. ISSN   1016-3328. S2CID   886700.