Michael Shub

Last updated
Michael Shub
Michael Shub.jpg
Michael Shub in April 2012
Born
Michael Ira Shub

(1943-08-17) August 17, 1943 (age 80)
NationalityAmerican
Alma mater University of California, Berkeley
Known for Blum Blum Shub pseudorandom number generator
Scientific career
Fields Mathematics
Institutions Brandeis University
University of California, Santa Cruz
Queens College at the City University of New York
Thomas J. Watson Research Center
University of Toronto
University of Buenos Aires

Michael Ira Shub (born August 17, 1943) is an American mathematician who has done research into dynamical systems and the complexity of real number algorithms.

Contents

Career

1967: Ph.D. and early career

In 1967, Shub obtained his Ph.D. degree at the University of California, Berkeley with a thesis entitled Endomorphisms of Compact Differentiable Manifolds. In his Ph.D. thesis, he introduced the notion of expanding maps, which gave the first examples of structurally stable strange attractors. His advisor was Stephen Smale. [1]

From 1967 to 1985, he worked at Brandeis University, the University of California, Santa Cruz and the Queens College at the City University of New York. In 1974, he proposed the Entropy Conjecture, an open problem in dynamical systems, which was proved by Yosef Yomdin for mappings in 1987. [2]

1985–2004: IBM research

From 1985 to 2004, he joined IBM's Thomas J. Watson Research Center. In 1987, Shub published his book Global Stability of Dynamical Systems, which is often used as a reference in introductory and advanced books on the subject of dynamical systems. [3] [4] [5] In 1993, Shub and Stephen Smale initiated a rigorous analysis of homotopy-based algorithms for solving systems of nonlinear algebraic equations, which has inspired much of the work in that area during the last two decades. [6]

From 1995 to 1997, Shub was the founding chair of the Society for the Foundations of Computational Mathematics. In 2001, Shub became a founding editor of their journal, Foundations of Computational Mathematics. [7]

1986: Blum Blum Shub

Shub, along with coauthors Lenore and Manuel Blum, described a simple, unpredictable, secure random number generator (see Blum Blum Shub). This random generator is useful from theoretical and practical perspectives. [8]

1989: Blum–Shub–Smale machine

In 1989, he proposed with Lenore Blum and Stephen Smale the notion of Blum–Shub–Smale machine, an alternative to the classical Turing model of computation. Their model is used to analyse the computability of functions. [9]

2004–2010: Post-IBM

From 2004 to 2010, he worked at the University of Toronto. [7] After 2010, he became a researcher at the University of Buenos Aires and at the Graduate Center of the City University of New York. [7] Since 2016, he has been Martin and Michele Cohen Professor and Chair of the Mathematics Department at City College of New York. [7]

Awards and recognition

Selected publications

Related Research Articles

Complexity characterises the behaviour of a system or model whose components interact in multiple ways and follow local rules, leading to non-linearity, randomness, collective dynamics, hierarchy, and emergence.

<span class="mw-page-title-main">Stephen Smale</span> American mathematician (born 1930)

Stephen Smale is an American mathematician, known for his research in topology, dynamical systems and mathematical economics. He was awarded the Fields Medal in 1966 and spent more than three decades on the mathematics faculty of the University of California, Berkeley, where he currently is Professor Emeritus, with research interests in algorithms, numerical analysis and global analysis.

<span class="mw-page-title-main">Manuel Blum</span> Venezuelan computer scientist

Manuel Blum is a Venezuelan born American computer scientist who received the Turing Award in 1995 "In recognition of his contributions to the foundations of computational complexity theory and its application to cryptography and program checking".

<span class="mw-page-title-main">Real computation</span> Concept in computability theory

In computability theory, the theory of real computation deals with hypothetical computing machines using infinite-precision real numbers. They are given this name because they operate on the set of real numbers. Within this theory, it is possible to prove interesting statements such as "The complement of the Mandelbrot set is only partially decidable."

<span class="mw-page-title-main">Lenore Blum</span> USA computer scientist and mathematician

Lenore Carol Blum is an American computer scientist and mathematician who has made contributions to the theories of real number computation, cryptography, and pseudorandom number generation. She was a distinguished career professor of computer science at Carnegie Mellon University until 2019 and is currently a professor in residence at the University of California, Berkeley. She is also known for her efforts to increase diversity in mathematics and computer science.

In computational complexity theory, R is the class of decision problems solvable by a Turing machine, which is the set of all recursive languages.

Joseph Frederick Traub was an American computer scientist. He was the Edwin Howard Armstrong Professor of Computer Science at Columbia University and External Professor at the Santa Fe Institute. He held positions at Bell Laboratories, University of Washington, Carnegie Mellon, and Columbia, as well as sabbatical positions at Stanford, Berkeley, Princeton, California Institute of Technology, and Technical University, Munich.

Smale's problems are a list of eighteen unsolved problems in mathematics proposed by Steve Smale in 1998 and republished in 1999. Smale composed this list in reply to a request from Vladimir Arnold, then vice-president of the International Mathematical Union, who asked several mathematicians to propose a list of problems for the 21st century. Arnold's inspiration came from the list of Hilbert's problems that had been published at the beginning of the 20th century.

In computation theory, the Blum–Shub–Smale machine, or BSS machine, is a model of computation introduced by Lenore Blum, Michael Shub and Stephen Smale, intended to describe computations over the real numbers. Essentially, a BSS machine is a Random Access Machine with registers that can store arbitrary real numbers and that can compute rational functions over reals in a single time step. It is closely related to the Real RAM model.

In computing, especially computational geometry, a real RAM is a mathematical model of a computer that can compute with exact real numbers instead of the binary fixed point or floating point numbers used by most actual computers. The real RAM was formulated by Michael Ian Shamos in his 1978 Ph.D. dissertation.

<span class="mw-page-title-main">Rufus Bowen</span> American mathematician

Robert Edward "Rufus" Bowen was an internationally known professor in the Department of Mathematics at the University of California, Berkeley, who specialized in dynamical systems theory. Bowen's work dealt primarily with axiom A systems, but the methods he used while exploring topological entropy, symbolic dynamics, ergodic theory, Markov partitions, and invariant measures "have application far beyond the axiom A systems for which they were invented." The Bowen Lectures at the University of California, Berkeley, are given in his honor.

In mathematical logic, computational complexity theory, and computer science, the existential theory of the reals is the set of all true sentences of the form

<span class="mw-page-title-main">Morris Hirsch</span> American mathematician

Morris William Hirsch is an American mathematician, formerly at the University of California, Berkeley.

<span class="mw-page-title-main">Richard M. Pollack</span> American mathematician

Richard M. Pollack was an American geometer who spent most of his career at the Courant Institute of Mathematical Sciences at New York University, where he was Professor Emeritus until his death.

<span class="mw-page-title-main">Foundations of Computational Mathematics</span>

Foundations of Computational Mathematics (FoCM) is an international nonprofit organization that supports and promotes research at the interface of mathematics and computation. It fosters interaction among mathematics, computer science, and other areas of computational science through conferences, events and publications.

Beresford Neill Parlett is an English applied mathematician, specializing in numerical analysis and scientific computation.

Peter Bürgisser is a Swiss mathematician and theoretical computer scientist who deals with algorithmic algebra and algebraic complexity theory.

Complexity and Real Computation is a book on the computational complexity theory of real computation. It studies algorithms whose inputs and outputs are real numbers, using the Blum–Shub–Smale machine as its model of computation. For instance, this theory is capable of addressing a question posed in 1991 by Roger Penrose in The Emperor's New Mind: "is the Mandelbrot set computable?"

<span class="mw-page-title-main">Felipe Cucker</span> Uruguayan mathematician

Juan Felipe Cucker Farkas is an Uruguayan mathematician and theoretical computer scientist who has done research into the complexity theory of the Blum–Shub–Smale computational model and the complexity of numerical algorithms in linear programming and numerical algebraic geometry.

<span class="mw-page-title-main">Anders C. Hansen</span> Norwegian mathematician

Anders C. Hansen is a Norwegian mathematician, who is currently a Professor of Mathematics at University of Cambridge, where he is the head of the Applied Functional and Harmonic Analysis group, and also Professor II at the University of Oslo. He works in functional analysis, harmonic analysis (applied), foundations of mathematics (computational), data science and numerical analysis.

References

  1. Michael Ira Shub at the Mathematics Genealogy Project
  2. Yomdin, Yosef (October 1987). "Volume growth and entropy". Israel Journal of Mathematics . Jerusalem, Israel: Hebrew University of Jerusalem. 57 (3): 285–300. doi: 10.1007/BF02766215 . S2CID   121442787.
  3. Devaney, Robert L. (1992). A First Course in Chaotic Dynamical Systems. Boulder, Colorado: Westview Press. pp. 14–127. ISBN   9780429983115.
  4. Wiggin, Stephen (1990). Introduction to Applied Nonlinear Systems and Chaos. New York City: Springer-Verlag. p. 470. ISBN   978-0387001777.
  5. Hasselblatt, Boris; Katok, Anatole (2002). Handbook of Dynamical Systems, Vol I. Amsterdam, Netherlands: Elsevier. p. 69. ISBN   0444826696.
  6. Bürgisser, Peter; Cucker, Felipe (2013). Condition: The Geometry of Numerical Algorithms. New York City: Springer-Verlag. p. 283. ISBN   978-3-642-38895-8.
  7. 1 2 3 4 5 York, The City College of New (2016-09-06). "Michael Shub". The City College of New York. Retrieved 2023-02-21.
  8. Stinson, Douglas R. (2005). Cryptography: Theory and Practice, Third Edition. Oxfordshire, England: Taylor & Francis. p. 336. ISBN   978-1584885085.
  9. Grädel, Erich (2007). "Algorithmic Model Theory". Finite Model Theory and Its Applications (PDF). New York City: Springer-Verlag. p. 217.
  10. 1 2 "Michael Shub: H-index & Awards - Academic Profile | Research.com". Research.com. Retrieved 2023-02-21.
  11. From Dynamics to Complexity - A conference celebrating the work of Shub. Toronto, Ontario, Canada: Fields Institute. May 7–11, 2012.
  12. "2016 Class of the Fellows of the AMS". American Mathematical Society . Retrieved November 16, 2015.