János Pach (born May 3, 1954)
is a mathematician and
computer scientist
A computer scientist is a person who is trained in the academic study of computer science.
Computer scientists typically work on the theoretical side of computation, as opposed to the hardware side on which computer engineers mainly focus (al ...
working in the fields of
combinatorics
Combinatorics is an area of mathematics primarily concerned with counting, both as a means and an end in obtaining results, and certain properties of finite structures. It is closely related to many other areas of mathematics and has many appl ...
and
discrete and computational geometry.
Biography
Pach was born and grew up in
Hungary. He comes from a noted academic family: his father, (1919–2001) was a well-known historian, and his mother Klára (née Sós, 1925–2020) was a university mathematics teacher; his maternal aunt
Vera T. Sós and her husband
Pál Turán are two of the best-known Hungarian mathematicians.
Pach received his
Candidate degree from the
Hungarian Academy of Sciences
The Hungarian Academy of Sciences ( hu, Magyar Tudományos Akadémia, MTA) is the most important and prestigious learned society of Hungary. Its seat is at the bank of the Danube in Budapest, between Széchenyi rakpart and Akadémia utca. Its ma ...
, in 1983, where his advisor was
Miklós Simonovits
Miklós Simonovits (4 September 1943 in Budapest) is a Hungarian mathematician who currently works at the Rényi Institute of Mathematics in Budapest and is a member of the Hungarian Academy of Sciences. He is on the advisory board of the journ ...
.
Since 1977, he has been affiliated with the
Alfréd Rényi Institute of Mathematics
The Alfréd Rényi Institute of Mathematics ( hu, Rényi Alfréd Matematikai Kutatóintézet) is the research institute in mathematics of the Hungarian Academy of Sciences. It was created in 1950 by Alfréd Rényi, who directed it until his death. ...
of the Hungarian Academy of Sciences.
[Research Fellows]
Rényi Institute
He was Research Professor at the
Courant Institute of Mathematical Sciences at
NYU[Personal website of János Pach](_blank)
NYU (since 1986), Distinguished Professor of Computer Science at
City College, CUNY (1992-2011), and Neilson Professor at
Smith College
Smith College is a Private university, private Liberal arts colleges in the United States, liberal arts Women's colleges in the United States, women's college in Northampton, Massachusetts. It was chartered in 1871 by Sophia Smith (Smith College ...
(2008-2009).
Between 2008 and 2019, he was Professor of the Chair of Combinatorial Geometry at
École Polytechnique Fédérale de Lausanne.
[János Pach appointed as a full professor of mathematics](_blank)
EPFL, December 12, 2007.
He was the program chair for the
International Symposium on Graph Drawing in 2004 and
Symposium on Computational Geometry in 2015. He is co-editor-in-chief of the journal ''
Discrete and Computational Geometry'', and he serves on the editorial boards of several other journals including ''
Combinatorica'', ''
SIAM Journal on Discrete Mathematics'', ''Computational Geometry'', ''
Graphs and Combinatorics'', ''Central European Journal of Mathematics'', and ''Moscow Journal of Combinatorics and Number Theory''.
He was an invited speaker at the Combinatorics session of the
International Congress of Mathematicians
The International Congress of Mathematicians (ICM) is the largest conference for the topic of mathematics. It meets once every four years, hosted by the International Mathematical Union (IMU).
The Fields Medals, the Nevanlinna Prize (to be rename ...
, in Seoul, 2014.
[List of Speakers at ICM.](_blank)
/ref>
He was a plenary speaker at the European Congress of Mathematics (Portorož), 2021.[List of Plenary Speakers at ECM.](_blank)
/ref>
Research
Pach has authored several books and over 300 research papers. He was one of the most frequent collaborators of Paul Erdős
Paul Erdős ( hu, Erdős Pál ; 26 March 1913 – 20 September 1996) was a Hungarian mathematician. He was one of the most prolific mathematicians and producers of mathematical conjectures of the 20th century. pursued and proposed problems in ...
, authoring over 20 papers with him and thus has an Erdős number of one.
Pach's research is focused in the areas of combinatorics
Combinatorics is an area of mathematics primarily concerned with counting, both as a means and an end in obtaining results, and certain properties of finite structures. It is closely related to many other areas of mathematics and has many appl ...
and discrete geometry.
In 1981, he solved Ulam's problem, showing that there exists
no universal planar graph.[
]
In the early 90s[AMS Meeting](_blank)
/ref>
together with Micha Perles
Micah (; ) is a given name.
Micah is the name of several people in the Hebrew Bible ( Old Testament), and means "Who is like God?" The name is sometimes found with theophoric extensions. Suffix theophory in '' Yah'' and in ''Yahweh'' results in ...
, he initiated the systematic study of extremal problems on topological and
geometric graphs.
Some of Pach's most-cited research work concerns the combinatorial complexity of families of curves in the plane and their applications to motion planning problems the maximum number of k-sets and halving lines that a planar point set may have, crossing numbers of graphs, embedding of planar graph
In graph theory, a planar graph is a graph that can be embedded in the plane, i.e., it can be drawn on the plane in such a way that its edges intersect only at their endpoints. In other words, it can be drawn in such a way that no edges cross ...
s onto fixed sets of points, and lower bounds for epsilon-nets.[.
][.
]
Awards and honors
Pach received the Grünwald Medal of the János Bolyai Mathematical Society (1982), the Ford Award from the Mathematical Association of America
The Mathematical Association of America (MAA) is a professional society that focuses on mathematics accessible at the undergraduate level. Members include university, college, and high school teachers; graduate and undergraduate students; pure a ...
(1990), and the Alfréd Rényi Prize The Alfréd Rényi Prize is awarded biennially by the Alfréd Rényi Institute of Mathematics of the Hungarian Academy of Science in honor of founder Alfréd Rényi. By the current rules it is given to one or two fellows of the Institute in recogni ...
from the Hungarian Academy of Sciences
The Hungarian Academy of Sciences ( hu, Magyar Tudományos Akadémia, MTA) is the most important and prestigious learned society of Hungary. Its seat is at the bank of the Danube in Budapest, between Széchenyi rakpart and Akadémia utca. Its ma ...
(1992). He was an Erdős Lecturer at Hebrew University of Jerusalem
The Hebrew University of Jerusalem (HUJI; he, הַאוּנִיבֶרְסִיטָה הַעִבְרִית בִּירוּשָׁלַיִם) is a public research university based in Jerusalem, Israel. Co-founded by Albert Einstein and Dr. Chaim Weiz ...
in 2005.
In 2011 he was listed as a fellow of the Association for Computing Machinery
The Association for Computing Machinery (ACM) is a US-based international learned society for computing. It was founded in 1947 and is the world's largest scientific and educational computing society. The ACM is a non-profit professional member ...
for his research in computational geometry
Computational geometry is a branch of computer science devoted to the study of algorithms which can be stated in terms of geometry. Some purely geometrical problems arise out of the study of computational geometric algorithms, and such problems ar ...
.
In 2014 he was elected as a member of Academia Europaea, and in 2015 as a fellow of the American Mathematical Society "for contributions to discrete and combinatorial geometry and to convexity and combinatorics."
In 2022 he was elected corresponding member of the Hungarian Academy of Sciences.[.]
Books
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See also
* Mountain climbing problem
In mathematics, the mountain climbing problem is a problem of finding the conditions that two functions forming profiles of a two-dimensional mountain must satisfy, so that two climbers can start on the bottom on the opposite sides of the mounta ...
References
External links
Personal website of János Pach
Chair of Combinatorial Geometry, EPFL
János Pach in the EPFL people directory
*
{{DEFAULTSORT:Pach, Janos
1954 births
Living people
American computer scientists
Hungarian computer scientists
20th-century American mathematicians
Graph theorists
Graph drawing people
20th-century Hungarian mathematicians
21st-century Hungarian mathematicians
City University of New York faculty
Courant Institute of Mathematical Sciences faculty
Hungarian Academy of Sciences
Researchers in geometric algorithms
Fellows of the Association for Computing Machinery
Academic staff of the École Polytechnique Fédérale de Lausanne
Fellows of the American Mathematical Society
21st-century American mathematicians