Lloyd N. Trefethen

Last updated

Nick Trefethen
Born
Lloyd Nicholas Trefethen

(1955-08-30) 30 August 1955 (age 63) [1] [2]
Alma mater
Known for Embree–Trefethen constant [3]
Spouse(s)
  • Anne Trefethen (née Daman)(m. 19882008)
  • Kate McLoughlin(m. 2011)
Childrenone son, one daughter [1]
Awards
Scientific career
Fields Numerical analysis
Institutions
Thesis Wave Propagation and Stability for Finite Difference Schemes  (1982)
Doctoral advisor Joseph E. Oliger [5]
Doctoral students
  • Jeffrey Baggett
  • Richard Baltensperger
  • Lehel Banjai [6]
  • Timo Betcke
  • Asgeir Birkisson [7]
  • Tobin Driscoll
  • Alan Edelman
  • Nick Hale
  • Louis Howell
  • Walter Mascarenhas
  • Hadrien Montanelli
  • Noel Nachtigal
  • Ricardo Pachon [8]
  • Satish Reddy
  • Mark Richardson
  • Thomas Schmelzer
  • Kim-Chuan Toh
  • Alex Townsend [9]
  • Divakar Viswanath
  • Thomas Wright [5]
Website people.maths.ox.ac.uk/trefethen

(Lloyd) Nicholas Trefethen, FRS [4] (born 30 August 1955) is professor of numerical analysis and head of the Numerical Analysis Group at the Mathematical Institute, University of Oxford. [10] [11] [12] [13]

Fellow of the Royal Society Elected Fellow of the Royal Society, including Honorary, Foreign and Royal Fellows

Fellowship of the Royal Society is an award granted to individuals that the Royal Society of London judges to have made a 'substantial contribution to the improvement of natural knowledge, including mathematics, engineering science, and medical science'.

Numerical analysis study of algorithms that use numerical approximation for the problems of mathematical analysis

Numerical analysis is the study of algorithms that use numerical approximation for the problems of mathematical analysis. Numerical analysis naturally finds application in all fields of engineering and the physical sciences, but in the 21st century also the life sciences, social sciences, medicine, business and even the arts have adopted elements of scientific computations. The growth in computing power has revolutionized the use of realistic mathematical models in science and engineering, and subtle numerical analysis is required to implement these detailed models of the world. For example, ordinary differential equations appear in celestial mechanics ; numerical linear algebra is important for data analysis; stochastic differential equations and Markov chains are essential in simulating living cells for medicine and biology.

Mathematical Institute, University of Oxford

The Mathematical Institute is the mathematics department at the University of Oxford, England. It forms one of the twelve departments of the Mathematical, Physical and Life Sciences Division in the University. The department is located between Somerville College and Green Templeton College on Woodstock Road, next to the Faculty of Philosophy.

Contents

Education

Trefethen is the son of mechanical engineer Lloyd M. Trefethen and codebreaker, poet, and English professor Florence Newman Trefethen. [1]

Lloyd MacGregor Trefethen was an American expert in fluid dynamics known for his invention of the heat pipe and his research on the Coriolis effect and card shuffling. He worked for many years as a professor of mechanical engineering at Tufts University.

Florence Marion Newman Trefethen (1921–2012) was an American codebreaker, historian of operations research, poet, and English professor.

He obtained his bachelor's degree from Harvard University in 1977 and his master's from Stanford University in 1980. His PhD was on Wave Propagation and Stability for Finite Difference Schemes supervised by Joseph E. Oliger at Stanford University. [5] [14] [15]

Harvard University private research university in Cambridge, Massachusetts, United States

Harvard University is a private Ivy League research university in Cambridge, Massachusetts, with about 6,700 undergraduate students and about 15,250 postgraduate students. Established in 1636 and named for its first benefactor, clergyman John Harvard, Harvard is the United States' oldest institution of higher learning. Its history, influence, and wealth have made it one of the world's most prestigious universities.

Stanford University private research university located in Stanford, California, United States

Leland Stanford Junior University is a private research university in Stanford, California. Stanford is known for its academic strength, wealth, proximity to Silicon Valley, and ranking as one of the world's top universities.

Career and research

Following his PhD, Trefethen went on to work at the Courant Institute of Mathematical Sciences in New York, Massachusetts Institute of Technology, and Cornell University, before being appointed to a chair at the University of Oxford and a Fellowship of Balliol College, Oxford. [16]

Courant Institute of Mathematical Sciences

The Courant Institute of Mathematical Sciences (CIMS) is an independent division of New York University (NYU) under the Faculty of Arts & Science that serves as a center for research and advanced training in computer science and mathematics. It is considered one of the leading and most prestigious mathematics schools and mathematical sciences research centers in the world. It is named after Richard Courant, one of the founders of the Courant Institute and also a mathematics professor at New York University from 1936 to 1972.

Massachusetts Institute of Technology University in Massachusetts

The Massachusetts Institute of Technology (MIT) is a private research university in Cambridge, Massachusetts. Founded in 1861 in response to the increasing industrialization of the United States, MIT adopted a European polytechnic university model and stressed laboratory instruction in applied science and engineering. It has since played a key role in the development of many aspects of modern science, engineering, and mathematics, and is widely known for its innovation and academic strength, making it one of the most prestigeous institutions of higher learning in the world. The Institute is a land-grant, sea-grant, and space-grant university, with an urban campus that extends more than a mile alongside the Charles River.

Cornell University Private Ivy League research university in Upstate New York

Cornell University is a private and statutory Ivy League research university in Ithaca, New York. Founded in 1865 by Ezra Cornell and Andrew Dickson White, the university was intended to teach and make contributions in all fields of knowledge—from the classics to the sciences, and from the theoretical to the applied. These ideals, unconventional for the time, are captured in Cornell's founding principle, a popular 1868 Ezra Cornell quotation: "I would found an institution where any person can find instruction in any study."

As of 2018, he has published around 140 journal papers spanning a wide range of areas within numerical analysis and applied mathematics, including non-normal eigenvalue problems and applications, spectral methods for differential equations, numerical linear algebra, fluid mechanics, computational complex analysis, and approximation theory. [17] He is perhaps best known for his work on pseudospectra of non-normal matrices and operators. This work covers theoretical aspects as well as numerical algorithms, and applications including fluid mechanics, numerical solution of partial differential equations, numerical linear algebra, shuffling of cards, random matrices, differential equations and lasers. Trefethen is currently an ISI highly cited researcher. [18]

Numerical linear algebra is the study of how matrix operations can be used to create computer algorithms which efficiently and accurately provide approximate answers to mathematical questions. It is a subfield of numerical analysis, and a type of linear algebra. Because computers use floating-point arithmetic, they cannot exactly represent irrational data, and many algorithms increase that imprecision when implemented by a computer. Numerical linear algebra uses properties of vectors and matrices to develop computer algorithms that minimize computer error while retaining efficiency and precision.

Fluid mechanics is the branch of physics concerned with the mechanics of fluids and the forces on them. It has applications in a wide range of disciplines, including mechanical, civil, chemical and biomedical engineering, geophysics, astrophysics, and biology.

Complex analysis Branch of mathematics studying functions of a complex variable

Complex analysis, traditionally known as the theory of functions of a complex variable, is the branch of mathematical analysis that investigates functions of complex numbers. It is useful in many branches of mathematics, including algebraic geometry, number theory, analytic combinatorics, applied mathematics; as well as in physics, including the branches of hydrodynamics, thermodynamics, and particularly quantum mechanics. By extension, use of complex analysis also has applications in engineering fields such as nuclear, aerospace, mechanical and electrical engineering.

Trefethen has written a number of books on numerical analysis including Numerical Linear Algebra [19] with David Bau, Spectral Methods in MATLAB, Schwarz–Christoffel Mapping with Tobin Driscoll, and Spectra and Pseudospectra: The Behavior of Nonnormal Matrices and Operators [20] with Mark Embree. [3] He has recently been heavily involved in the creation and development of the MATLAB-based Chebfun software project.

Mark Embree is professor of computational and applied mathematics at Virginia Tech in Blacksburg, Virginia. Until 2013, he was a professor of computational and applied mathematics at Rice University in Houston, Texas.

MATLAB multi-paradigm numerical computing environment

MATLAB is a multi-paradigm numerical computing environment and proprietary programming language developed by MathWorks. MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages, including C, C++, C#, Java, Fortran and Python.

Chebfun is a free/open-source software system written in MATLAB for numerical computation with functions of a real variable. It is based on the idea of overloading MATLAB's commands for vectors and matrices to analogous commands for functions and operators. Thus, for example, whereas the SUM command in MATLAB adds up the elements of a vector, the SUM command in Chebfun evaluates a definite integral. Similarly the backslash command in MATLAB becomes a Chebfun command for solving differential equations.

In 2013 he proposed a new formula to calculate the BMI of a person: [21] [22]

(International System of Units)

Notable publications

Awards and honours

Trefethen was the first winner of the Leslie Fox Prize for Numerical Analysis. He is a fellow of the American Mathematical Society, [24] and a member of the National Academy of Engineering in the United States. Trefethen was elected a Fellow of the Royal Society (FRS) in 2005, [4] his certificate of election reads:

Nick Trefethen is distinguished for his many seminal contributions to Numerical Analysis and its applications in Applied Mathematics and in Engineering Science. His research spans theory, algorithms, software and physical applications, particularly involving eigenvalues, pseudospectra – a concept which he introduced – and dynamics. He has an international reputation for his work on nonnormal matrices and operators. He has also made major contributions to finite difference and spectral methods for partial differential equations, numerical linear algebra, and complex analysis. His monograph Numerical Linear Algebra (SIAM, 1997) is one of the SIAM's best selling books and has already been through five printings. [4]

In 2010 Trefethen was awarded the Gold Medal of the Institute of Mathematics and its Applications in recognition of his "outstanding contributions to mathematics and its applications over a period of years". [25] In 2013 Trefethen was awarded the Naylor Prize and lectureship in Applied Mathematics from the London Mathematical Society. [26]

Personal life

Trefethen has one son and one daughter from his first marriage to Anne Elizabeth Trefethen (née Daman). [1]

Related Research Articles

Linear algebra branch of mathematics

Linear algebra is the branch of mathematics concerning linear equations such as

In linear algebra, a diagonal matrix is a matrix in which the entries outside the main diagonal are all zero. The term usually refers to square matrices. An example of a 2-by-2 diagonal matrix is ; the following matrix is a 3-by-3 diagonal matrix: . An identity matrix of any size, or any multiple of it, will be a diagonal matrix.

In the mathematical discipline of linear algebra, a matrix decomposition or matrix factorization is a factorization of a matrix into a product of matrices. There are many different matrix decompositions; each finds use among a particular class of problems.

In mathematics, spectral theory is an inclusive term for theories extending the eigenvector and eigenvalue theory of a single square matrix to a much broader theory of the structure of operators in a variety of mathematical spaces. It is a result of studies of linear algebra and the solutions of systems of linear equations and their generalizations. The theory is connected to that of analytic functions because the spectral properties of an operator are related to analytic functions of the spectral parameter.

In mathematics, operator theory is the study of linear operators on function spaces, beginning with differential operators and integral operators. The operators may be presented abstractly by their characteristics, such as bounded linear operators or closed operators, and consideration may be given to nonlinear operators. The study, which depends heavily on the topology of function spaces, is a branch of functional analysis.

Numerical partial differential equations is the branch of numerical analysis that studies the numerical solution of partial differential equations (PDEs).

In linear algebra, an eigenvector or characteristic vector of a linear transformation is a non-zero vector that changes by only a scalar factor when that linear transformation is applied to it. More formally, if T is a linear transformation from a vector space V over a field F into itself and v is a vector in V that is not the zero vector, then v is an eigenvector of T if T(v) is a scalar multiple of v. This condition can be written as the equation

In mathematics, the pseudospectrum of an operator is a set containing the spectrum of the operator and the numbers that are "almost" eigenvalues. Knowledge of the pseudospectrum can be particularly useful for understanding non-normal operators and their eigenfunctions.

Nicholas John Higham FRS is a British numerical analyst. He is Royal Society Research Professor and Richardson Professor of Applied Mathematics in the School of Mathematics at the University of Manchester.

Leslie Fox was a British mathematician noted for his contribution to numerical analysis.

In the mathematical field of linear algebra and convex analysis, the numerical range or field of values of a complex n × n matrix A is the set

Matrix (mathematics) Two-dimensional array of numbers with specific operations

In mathematics, a matrix is a rectangular array of numbers, symbols, or expressions, arranged in rows and columns. For example, the dimensions of the matrix below are 2 × 3, because there are two rows and three columns:

The following is a timeline of numerical analysis after 1945, and deals with developments after the invention of the modern electronic computer, which began during Second World War. For a fuller history of the subject before this period, see timeline and history of mathematics.

Alan Edelman American mathematician and computer scientist

Alan Stuart Edelman is an American mathematician and computer scientist. He is a Professor of Applied Mathematics at the Massachusetts Institute of Technology and a Principal Investigator at the MIT Computer Science and AI Laboratory (CSAIL) where he leads a group in Applied Computing. In 2004 Professor Edelman founded Interactive Supercomputing, acquired by Microsoft.

References

  1. 1 2 3 4 TREFETHEN, Prof. Lloyd Nicholas, (Nick). ukwhoswho.com. Who's Who. 2015 (online Oxford University Press ed.). A & C Black, an imprint of Bloomsbury Publishing plc. Closed Access logo transparent.svg (subscription required)
  2. "New directions in Numerical Computation, 25–28 August 2015: In Celebration of Nick Trefethen's 60th birthday". University of Oxford. Archived from the original on 4 April 2015.
  3. 1 2 Embree, M.; Trefethen, L. N. (1999). "Growth and decay of random Fibonacci sequences" (PDF). Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 455 (1987): 2471. Bibcode:1999RSPSA.455.2471T. CiteSeerX   10.1.1.33.1658 . doi:10.1098/rspa.1999.0412.
  4. 1 2 3 4 "Certificate of candidature and election: Trefethen, Lloyd Nicholas, EC/2005/40". London: The Royal Society. Archived from the original on 22 January 2014.
  5. 1 2 3 Lloyd N. Trefethen at the Mathematics Genealogy Project
  6. Banjai, Lehel. (2003). Computation of conformal maps by fast multipole method accelerated Schwarz-Christoffel transformation (PhD thesis). University of Oxford.
  7. Birkisson, Asgeir (2013). Numerical solution of nonlinear boundary value problems for ordinary differential equations in the continuous framework (PhD thesis). University of Oxford.
  8. Pachon, Ricardo (2010). Algorithms for polynomial and rational approximation (PhD thesis). University of Oxford. Open Access logo PLoS transparent.svg
  9. Townsend, Alex (2014). Computing with functions in two dimensions (PhD thesis). University of Oxford.
  10. Lloyd N. Trefethen's publications indexed by the Scopus bibliographic database. (subscription required)
  11. Lloyd N. Trefethen publications indexed by Google Scholar
  12. Lloyd N. Trefethen at DBLP Bibliography Server Blue pencil.svg
  13. Nachtigal, N. L. M.; Reddy, S. C.; Trefethen, L. N. (1992). "How Fast are Nonsymmetric Matrix Iterations?". SIAM Journal on Matrix Analysis and Applications. 13 (3): 778. CiteSeerX   10.1.1.210.62 . doi:10.1137/0613049.
  14. Trefethen, Lloyd Nicholas (1982). Wave Propagation and Stability for Finite Difference Schemes (PhD thesis). Stanford University. OCLC   9136203.
  15. Lloyd N. Trefethen author profile page at the ACM Digital Library
  16. "SNC '07 Invited Speakers" . Retrieved 26 April 2008.
  17. "Nick Trefethen publication list".
  18. "T – Research Analytics – Thomson Reuters". Highlycited.com. 15 September 2011. Retrieved 12 February 2013.
  19. Stewart, G. W. (1999). "Review: Numerical linear algebra, by L. N. Trefethen and D. Bau". Math. Comp. 68 (225): 453–454. doi:10.1090/S0025-5718-99-01069-8.
  20. Higham, Nicholas J. (2007). "Review: Spectra and pseudospectra: the behavior of nonnormal matrices and operators, by L. N. Trefethen and M. Embree". Bull. Amer. Math. Soc. (N.S.). 44 (2): 277–284. doi:10.1090/s0273-0979-06-01128-1.
  21. "New BMI (New Body Mass Index)".
  22. Stephenson, Wesley (29 January 2013). "Does the BMI need correcting?". BBC News.
  23. Trefethen, L. N.; Trefethen, A. E.; Reddy, S. C.; Driscoll, T. A. (1993). "Hydrodynamic Stability Without Eigenvalues". Science. 261 (5121): 578–584. Bibcode:1993Sci...261..578T. doi:10.1126/science.261.5121.578. PMID   17758167.
  24. List of Fellows of the American Mathematical Society. Retrieved 27 August 2013.
  25. "IMA Gold Medal" . Retrieved 16 May 2018. Institute of Mathematics and its Applications
  26. "List of LMS prize winners". London Mathematical Society. Retrieved 25 November 2014.