Mikołaj Bojańczyk

{{Short description|Polish theoretical computer scientist and logician}}

{{Infobox scientist

| honorific_prefix =

| name = Mikołaj Bojańczyk

| honorific_suffix =

| native_name =

| native_name_lang =

| image =

| image_size =

| image_upright =

| alt =

| caption =

| birth_date = {{birth date and age|1977|6|8}}

| birth_place =

| death_date =

| death_place =

| death_cause =

| resting_place =

| resting_place_coordinates =

| other_names =

| citizenship =

| nationality =

| fields = {{unbulleted list|Automata theory|Logic in computer science}}

| workplaces = {{unbulleted list|Warsaw University}}

| patrons =

| education =

| alma_mater = Warsaw University

| thesis_title =

| thesis_url =

| thesis_year =

| doctoral_advisor = Igor Walukiewicz

| academic_advisors =

| doctoral_students =

| notable_students =

| known_for = Tree walking automata

| influences =

| influenced =

| awards = Presburger Award (2010)
Kuratowski Prize (2007)

| author_abbrev_bot =

| author_abbrev_zoo =

| spouse =

| partner =

| children =

| signature =

| signature_alt =

| website = {{URL|https://www.mimuw.edu.pl/~bojan/}}

| footnotes =

}}

Mikołaj Bojańczyk (born 1977) is a Polish theoretical computer scientist and logician known for settling open problems on tree walking automata{{Cite journal|last1=Bojańczyk|first1=Mikołaj|last2=Colcombet|first2=Thomas|title=Tree-walking automata cannot be determinized|journal=Theoretical Computer Science|language=en|volume=350|issue=2–3|pages=164–173|doi=10.1016/j.tcs.2005.10.031|year=2006|doi-access=free}}{{Cite journal|last1=Bojańczyk|first1=M.|last2=Colcombet|first2=T.|date=2008-01-01|title=Tree-Walking Automata Do Not Recognize All Regular Languages|journal=SIAM Journal on Computing|volume=38|issue=2|pages=658–701|doi=10.1137/050645427|issn=0097-5397|citeseerx=10.1.1.100.7065}} jointly with Thomas Colcombet, and for contributions to logic in automata theory.{{Cite journal|last1=Bojańczyk|first1=Mikołaj|last2=Parys|first2=Paweł|date=2011-07-01|title=XPath Evaluation in Linear Time|journal=Journal of the ACM|volume=58|issue=4|pages=17:1–17:33|doi=10.1145/1989727.1989731|issn=0004-5411|citeseerx=10.1.1.217.4646|s2cid=47301339}}{{Cite journal|last1=Bojańczyk|first1=Mikoaj|last2=Muscholl|first2=Anca|author2-link= Anca Muscholl |last3=Schwentick|first3=Thomas|last4=Segoufin|first4=Luc|date=2009-05-01|title=Two-variable Logic on Data Trees and XML Reasoning|journal=Journal of the ACM|volume=56|issue=3|pages=13:1–13:48|doi=10.1145/1516512.1516515|issn=0004-5411|citeseerx=10.1.1.157.4510|s2cid=52817406}} He is a professor at Warsaw University.