Vesa
Halava
Professor, Mathematics
Links
Areas of expertise
computability
automata and formal languages
logic
combinatorics on words
Biography
I am a Professor of Discrete Mathematics and Theoretical Computer Science.
Teaching
I teach two course in Logic, basic course and advanced level course. I also teach Analysis I for (the first year) students of mathematics.
Research
My main field of research is in the field of Computability, more precisely on undecidable problems in automata and formal langauges and in the semigroups generated by integer matrices. Recently, I have also focused on the Foundations of Computation and related issues in the Foundations of Mathematics -- in Logic and Set Theory. I have also published articles in Combinatorics on Words.
Publications
Word Problem for deterministic and reversible semi-Thue systems (2012)
TUCS Publication Series
(Julkaistu kehittämis- tai tutkimusraportti taikka -selvitys (D4))
New Proof for the Undecidability of the Circular PCP (2012)
TUCS Publication Series
(Julkaistu kehittämis- tai tutkimusraportti taikka -selvitys (D4))
Words, Graphs, Automata, and Languages: Special Issue Honoring the 60th Birthday of Professor Tero Harju (2012)
pecial Issue Honoring the 60th Birthday of Professor Tero Harju: Preface
Fundamenta Informaticae
(Toimitustyö tieteelliselle lehdelle, kokoomateokselle tai konferenssijulkaisulle (C2))
REDUCTION TREE OF THE BINARY GENERALIZED POST CORRESPONDENCE PROBLEM (2011)
International Journal of Foundations of Computer Science
(Vertaisarvioitu alkuperäisartikkeli tai data-artikkeli tieteellisessä aikakauslehdessä (A1))
A new proof for the decidability of D0L ultimate periodicity (2011)
Electronic Proceedings in Theoretical Computer Science
(Vertaisarvioitu artikkeli konferenssijulkaisussa (A4))
On the Periodicity of Morphic Words (2010)
Lecture Notes in Computer Science
(Vertaisarvioitu artikkeli konferenssijulkaisussa (A4))
On the Joint Spectral Radius for Bounded Matrix Languages (2010)
Lecture Notes in Computer Science
(Vertaisarvioitu artikkeli konferenssijulkaisussa (A4))
ON THE NUMBER OF SQUARES IN PARTIAL WORDS (2010)
RAIRO: Informatique Théorique et Applications / RAIRO: Theoretical Informatics and Applications
(Vertaisarvioitu alkuperäisartikkeli tai data-artikkeli tieteellisessä aikakauslehdessä (A1))
Reachability problems (RP 2008) - Preface (2009)
International Journal of Foundations of Computer Science
(Toimitustyö tieteelliselle lehdelle, kokoomateokselle tai konferenssijulkaisulle (C2))
Overlap-freeness in infinite partial words (2009)
Theoretical Computer Science
(Vertaisarvioitu alkuperäisartikkeli tai data-artikkeli tieteellisessä aikakauslehdessä (A1))