Béla Bollobás | |
---|---|
![]() | |
Born | [1] Budapest, Hungary | 3 August 1943
Alma mater | Eötvös Loránd University Trinity College, Cambridge |
Known for | Functional analysis combinatorics Extremal graph theory percolation theory graph polynomials |
Spouse | Gabriella Bollobás [2] |
Awards | Senior Whitehead Prize (2007) Bocskai Prize (2015) Széchenyi Prize (2017) |
Scientific career | |
Fields | Mathematics Random graphs Extremal graph theory |
Institutions | Eötvös Loránd University University of Cambridge University of Memphis |
Doctoral advisor | László Fejes Tóth Paul Erdős [3] Frank Adams [4] |
Doctoral students | |
Website | royalsociety dpmms |
Béla Bollobás FRS (born 3 August 1943) is a Hungarian-born British mathematician who has worked in various areas of mathematics, including functional analysis, combinatorics, graph theory, and percolation. He was strongly influenced by Paul Erdős from the age of 14. [2] [6] [7] [8]
As a student, he took part in the first three International Mathematical Olympiads, winning two gold medals. [9] Paul Erdős invited Bollobás to lunch after hearing about his victories, and they kept in touch afterward. Bollobás' first publication was a joint publication with Erdős [10] on extremal problems in graph theory, written when he was in high school in 1962.
With Erdős's recommendation to Harold Davenport and a long struggle for permission from the Hungarian authorities, Bollobás was able to spend an undergraduate year in Cambridge, England. However, the authorities denied his request to return to Cambridge for doctoral study. A similar scholarship offer from Paris was also quashed. He wrote his first doctorate in discrete geometry under the supervision of László Fejes Tóth and Paul Erdős in Budapest University, 1967, after which he spent a year in Moscow with Israïl Moiseevich Gelfand. After spending a year at Christ Church, Oxford, where Michael Atiyah held the Savilian Chair of Geometry, he vowed never to return to Hungary due to his disillusion with the 1956 Soviet intervention. He then went to Trinity College, Cambridge, where in 1972 he received a second PhD in functional analysis, studying Banach algebras under the supervision of Frank Adams. [4] [2] Bollobás recalled, "By then, I said to myself, 'If I ever manage to leave Hungary, I won't return.'" In 1970, he was awarded a fellowship to the college. [11]
His main area of research is combinatorics, particularly graph theory. His chief interests are in extremal graph theory and random graph theory. In 1996 he resigned his university post, but remained a Fellow of Trinity College, Cambridge.
Bollobás has been a Fellow of Trinity College, Cambridge, since 1970; in 1996 he was appointed to the Jabie Hardin Chair of Excellence at the University of Memphis, and in 2005 he was awarded a senior research fellowship at Trinity College. [2]
Bollobás has proved results on extremal graph theory, functional analysis, the theory of random graphs, graph polynomials and percolation. For example, with Paul Erdős he proved results about the structure of dense graphs; he was the first to prove detailed results about the phase transition in the evolution of random graphs; he proved that the chromatic number of the random graph on n vertices is asymptotically n/2 log n; with Imre Leader he proved basic discrete isoperimetric inequalities; with Richard Arratia and Gregory Sorkin he constructed the interlace polynomial; with Oliver Riordan he introduced the ribbon polynomial (now called the Bollobás–Riordan polynomial); with Andrew Thomason, József Balogh, Miklós Simonovits, Robert Morris and Noga Alon he studied monotone and hereditary graph properties; with Paul Smith and Andrew Uzzell he introduced and classified random cellular automata with general homogeneous monotone update rules; with József Balogh, Hugo Duminil-Copin and Robert Morris he studied bootstrap percolation; with Oliver Riordan he proved that the critical probability in random Voronoi percolation in the plane is 1/2; and with Svante Janson and Oliver Riordan he introduced a very general model of heterogeneous sparse random graphs.
In addition to over 350 research papers on mathematics, Bollobás has written several books, including the research monographs Extremal Graph Theory in 1978, Random Graphs in 1985 and Percolation (with Oliver Riordan) in 2006, the introductory books Modern Graph Theory for undergraduate courses in 1979, Combinatorics and Linear Analysis in 1990, and the collection of problems The Art of Mathematics – Coffee Time in Memphis in 2006, with drawings by Gabriella Bollobás. He has also edited a number of books, including Littlewood's Miscellany.
Bollobás's research students have included Keith Ball at Warwick, Graham Brightwell at LSE, Timothy Gowers (who was awarded a Fields Medal in 1998 and is Rouse Ball Professor of Mathematics), Imre Leader at the University of Cambridge, Jonathan Partington at Leeds, and Charles Read at Leeds, who died in 2015.
Bollobás is an External Member of the Hungarian Academy of Sciences; in 2007 he was awarded the Senior Whitehead Prize by the London Mathematical Society. [12] In 2011 he was elected a Fellow of the Royal Society for his major contributions to many different areas of mathematics within the broad field of combinatorics, including random graphs, percolation, extremal graphs, set systems and isoperimetric inequalities. The citation also recognises the profound influence of his textbooks in many of these areas, and his key role in establishing Britain as one of the leading countries in probabilistic and extremal combinatorics. [13] In 2012 he became a fellow of the American Mathematical Society. [14]
Bollobás was elected a Fellow of the Royal Society in 2011. His nomination reads
Béla Bollobás is one of the world's leading mathematicians in combinatorics. He has a huge published output, which includes major contributions to many different branches of this very large area, such as random graphs, percolation, extremal graphs and set systems, isoperimetric inequalities, and more. In addition, through his classic textbooks, he has more or less defined many of these subjects. Britain is now one of the strongest countries for probabilistic and extremal combinatorics in the world: this is almost entirely due to Bollobás's influence. [15]
In 1998 he was an invited speaker of the International Congress of Mathematicians in Berlin. [16] He was elected Foreign Member of the Polish Academy of Sciences in 2013, a Member of the Academy of Europea in 2017 and a member of Academia Brasileira Ciencias (ABC) in 2023. He received an honorary doctorate from Adam Mickiewicz University, Poznań in 2013. In 2016 he received the Bocskai Prize and the Széchenyi Prize in 2017.
His father was a physician. His wife, Gabriella Bollobás, born in Budapest, was an actress and a musician in Hungary before moving to England to become a sculptor. She made busts of mathematicians and scientists, including Paul Erdős, Bill Tutte, George Batchelor, John von Neumann, Paul Dirac, and Stephen Hawking, as well as a cast bronze of David Hilbert. [2] He has one son, Mark.
Bollobás is also a sportsman, having represented the University of Oxford at modern pentathlon and the University of Cambridge at fencing. [17] [18]
In statistical physics and mathematics, percolation theory describes the behavior of a network when nodes or links are added. This is a geometric type of phase transition, since at a critical fraction of addition the network of small, disconnected clusters merge into significantly larger connected, so-called spanning clusters. The applications of percolation theory to materials science and in many other disciplines are discussed here and in the articles Network theory and Percolation.
In mathematics, random graph is the general term to refer to probability distributions over graphs. Random graphs may be described simply by a probability distribution, or by a random process which generates them. The theory of random graphs lies at the intersection between graph theory and probability theory. From a mathematical perspective, random graphs are used to answer questions about the properties of typical graphs. Its practical applications are found in all areas in which complex networks need to be modeled – many random graph models are thus known, mirroring the diverse types of complex networks encountered in different areas. In a mathematical context, random graph refers almost exclusively to the Erdős–Rényi random graph model. In other contexts, any graph model may be referred to as a random graph.
Extremal graph theory is a branch of combinatorics, itself an area of mathematics, that lies at the intersection of extremal combinatorics and graph theory. In essence, extremal graph theory studies how global properties of a graph influence local substructure. Results in extremal graph theory deal with quantitative connections between various graph properties, both global and local, and problems in extremal graph theory can often be formulated as optimization problems: how big or small a parameter of a graph can be, given some constraints that the graph has to satisfy? A graph that is an optimal solution to such an optimization problem is called an extremal graph, and extremal graphs are important objects of study in extremal graph theory.
Paul Erdős was a Hungarian mathematician. He was one of the most prolific mathematicians and producers of mathematical conjectures of the 20th century. Erdős pursued and proposed problems in discrete mathematics, graph theory, number theory, mathematical analysis, approximation theory, set theory, and probability theory. Much of his work centered around discrete mathematics, cracking many previously unsolved problems in the field. He championed and contributed to Ramsey theory, which studies the conditions in which order necessarily appears. Overall, his work leaned towards solving previously open problems, rather than developing or exploring new areas of mathematics.
Pál Turán also known as Paul Turán, was a Hungarian mathematician who worked primarily in extremal combinatorics.
Richard Kenneth Guy was a British mathematician. He was a professor in the Department of Mathematics at the University of Calgary. He is known for his work in number theory, geometry, recreational mathematics, combinatorics, and graph theory. He is best known for co-authorship of Winning Ways for your Mathematical Plays and authorship of Unsolved Problems in Number Theory. He published more than 300 scholarly articles. Guy proposed the partially tongue-in-cheek "strong law of small numbers", which says there are not enough small integers available for the many tasks assigned to them – thus explaining many coincidences and patterns found among numerous cultures. For this paper he received the MAA Lester R. Ford Award.
László Lovász is a Hungarian mathematician and professor emeritus at Eötvös Loránd University, best known for his work in combinatorics, for which he was awarded the 2021 Abel Prize jointly with Avi Wigderson. He was the president of the International Mathematical Union from 2007 to 2010 and the president of the Hungarian Academy of Sciences from 2014 to 2020.
Noga Alon is an Israeli mathematician and a professor of mathematics at Princeton University noted for his contributions to combinatorics and theoretical computer science, having authored hundreds of papers.
Peter Jephson Cameron FRSE is an Australian mathematician who works in group theory, combinatorics, coding theory, and model theory. He is currently half-time Professor of Mathematics at the University of St Andrews, and Emeritus Professor at Queen Mary University of London.
János Pach is a mathematician and computer scientist working in the fields of combinatorics and discrete and computational geometry.
In graph theory, an area of mathematics, an equitable coloring is an assignment of colors to the vertices of an undirected graph, in such a way that
Geoffrey Richard GrimmettOLY is an English mathematician known for his work on the mathematics of random systems arising in probability theory and statistical mechanics, especially percolation theory and the contact process. He is the Professor of Mathematical Statistics in the Statistical Laboratory, University of Cambridge, and was the Master of Downing College, Cambridge, from 2013 to 2018.
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 journal Combinatorica. He is best known for his work in extremal graph theory and was awarded Széchenyi Prize in 2014. Among other things, he discovered the method of progressive induction which he used to describe graphs which do not contain a predetermined graph and the number of edges is close to maximal. With Lovász, he gave a randomized algorithm using O(n7 log2n) separation calls to approximate the volume of a convex body within a fixed relative error.
Paul Allen Catlin was a mathematician, professor of mathematics who worked in graph theory and number theory. He wrote a significant paper on the series of chromatic numbers and Brooks' theorem, titled Hajós graph coloring conjecture: variations and counterexamples.
Richard Alejandro Arratia is a mathematician noted for his work in combinatorics and probability theory.
Robert (Rob) Morris is a mathematician who works in combinatorics, probability, graph theory and Ramsey theory. He is a researcher at IMPA.
Ilona Palásti (1924–1991) was a Hungarian mathematician who worked at the Alfréd Rényi Institute of Mathematics. She is known for her research in discrete geometry, geometric probability, and the theory of random graphs. With Alfréd Rényi and others, she was considered to be one of the members of the Hungarian School of Probability.
William G. Brown is a Canadian mathematician specializing in graph theory. He is a professor emeritus of mathematics at McGill University.
József Balogh is a Hungarian-American mathematician, specializing in graph theory and combinatorics.
Julian Sahasrabudhe is a Canadian mathematician who is an assistant professor of mathematics at the University of Cambridge, in their Department of Pure Mathematics and Mathematical Statistics. His research interests are in extremal and probabilistic combinatorics, Ramsey theory, random polynomials and matrices, and combinatorial number theory.
{{cite web}}
: CS1 maint: archived copy as title (link)