«Science History»
Young, Lai-Sang

Lai-Sang Young


Born: 1952 in Hong Kong


Lai-Sang Young received her primary and secondary school education in Hong Kong. Her teaching there was partly in Cantonese and partly in English. She emigrated to the United States where she began her higher education.

Entering the University of Wisconsin, Madison, Young received her B.A. in 1973. She then moved to the University of California at Berkeley where she was awarded an M.A. in 1976 and a Ph.D. in 1978. After the award of her doctorate Young taught at Northwestern University for a year beginning in 1978. We mention below the time she spent at the University of Warwick, England, and following this, in 1980, she also taught at Michigan State University.

Following this she held a position at the University of Arizona, and concurrently she worked at at the University of California at Los Angeles where she became Professor of Mathematics. During 1983-84 she held a visiting position at the Mathematical Sciences Research Institute at Berkeley. Following this she was awarded an Alfred P Sloan Fellowship for 1985-86 which enabled her to spend this year at the University of Bielefeld in Germany. In 1989 she held another visiting position, this time at the Institute for Advanced Study at Princeton.

Young's first paper was published in 1977 and gives results which she proved at the beginning of her graduate studies. The paper Entropy of continuous flows on compact 2-manifolds was published in Topology and shows that a continuous one-dimensional flow on a 2-dimensional manifold has zero topological entropy. In each of 1979, 1980 and 1981 one of Young's papers appeared, these being: A closing lemma on the interval; Non absolutely continuous foliations for an Anosov diffeomorphism; and On the prevalence of horseshoes.

In 1979-80 a symposium was held at the University of Warwick in England on Dynamical systems and turbulence. Young attended this and was one of the two editors, the other being David Rand, of the Proceedings of the Symposium which was published in 1981. Having mentioned all this work by Young on dynamical systems perhaps it is time to say briefly what a dynamical system is. It would be best for us give Young's own description of the area of dynamical systems as she describes it at the beginning of her clearly written article Developments in chaotic dynamics which appeared in the Notices of the American Mathematical Society in 1998:-

Dynamical systems as a mathematical discipline goes back to Poincaré, who developed a qualitative approach to problems that arose from celestial mechanics. The subject has expanded considerably in scope and has undergone some fundamental changes in the last three decades. Today it stands at the crossroads of several areas of mathematics, including analysis, geometry, topology, probability, and mathematical physics. It is generally regarded as a study of the iteration of maps, of time evolution of differential equations, and of group actions on manifolds.
In 1993 Young was honoured with the award of the Ruth Lyttle Satter Prize. The citation for this prize reads:-
Young has played a leading role in the investigation of the statistical (or ergodic) properties of dynamical systems and has developed important and difficult techniques which have done much to clarify the subject. In one major paper she established the exponential decay of correlations for a certain class of quadratic maps, which are one of the simplest kinds of nonuniformly hyperbolic systems. this implies that the limit theorems of probability hold in this case. Although similar results were known for [systems which have uniform hyperbolicity], nothing was known in the nonuniform case, and the numerical evidence was contradictory. Thus, her result was both unexpected and deep.

A second outstanding piece of work is her joint paper with Benedicks, in which they study the statistical properties of the Hénon attractor. They show that orbits from a subset of the basin of attraction of positive measure have a common distribution in the limit ... This explains why we "see" the attractor on the computer.

The joint paper referred to here is one Young wrote with Michael Benedicks which they published in the Ergodic Theory of Dynamical Systems in 1992.

Young's response to the presentation of the Ruth Lyttle Satter Prize was to thank Joan Birman for creating the prize and the committee who selected her which was chaired by the previous winner Dusa McDuff. She then continued:-
I ... want to take this opportunity to express my gratitude to my teachers and friends for their support and guidence over the years.

I would like to tell you a little about my work. For the last ten years one of my projects has been to study the dynamics of strange sttractors. Numerically it has been observed time and time again that if we randomly pick a point near an attractor and plot the first n points of its orbit, then the same picture emerges independently of the initial condition. This suggests the existence of a natural invariant measure, one that governs the asymptotic distribution of almost all points in the basin of attraction.

After giving details of how this measure was discovered, and her own contributions, but she explained that there had been an embarrassing lack of examples. Her work with Benedicks mentioned in the citation gave important examples. She continued:-
These are of course only the first examples. We have a long way to go before we understand the ergodic theory of strange attractors.
Young then spoke about women in mathematics:-
There is no doubt that our situation has improved; life in academia for women is easier for my generation than the generation before. I feel that more institutional support is still needed for women who try to juggle career and family, and a conscious effort on our part is necessary if we are to rid ourselves of the cultural prejudices that have existed for so long.
Young has published several excellent surveys of her area and her own contributions to it. In 1993, the same year that she received the Ruth Lyttle Satter Prize, Young lectured at the Real and complex dynamical systems meeting in Hillerod, Denmark. Her contribution Ergodic theory of differentiable dynamical systems appeared in the resulting 1995 publication presents:-
A comprehensive self-contained survey of the results on ergodic theory of differentiable dynamical systems achieved in the last two decades...
More recent surveys include her invited lecture to the International Congress of Mathematicians in 1994. An article based on her lecture Ergodic theory of attractors was published in the Proceedings. It surveys:-
... recent developments in the study of the ergodic properties of attractors of certain dissipative surface diffeomorphisms. The motivating prototype is the Henon family of plane diffeomorphisms ...
Young had been an invited plenary speaker at further meetings over the last few years including: the International Congress of Mathematical Physics (1997); the American Mathematical Society Annual Meeting (1998); and the Society for Industrial and Applied Mathematics Annual Meeting (1999). At the first of these she lectured on the Ergodic theory of chaotic dynamical systems.

Young gives the following list of her current research interests:

  1. measurements of dynamical complexity, including entropy, Lyapunov exponents and fractal dimension;
  2. analysis of strange attractors;
  3. cumulative effects of small random perturbations (or "noise") on the long term behaviour of dynamical systems;
  4. correlation decay and other probabilistic laws for chaotic systems.
Finally we should mention two further prestigious awards which Young has received. She received a Faculty Award for Women in Science and Engineering from the National Science Foundation for 1991-1996, and a Guggenheim Fellowship for 1997-98.

Young, who is currently Henry & Lucy Moses Professor of Science at New York University's Courant Institute of Mathematical Sciences, was elected as a Fellow of the American Academy of Arts and Sciences in 2004. In the following year she was the Association for Women in Mathematics' Noether Lecturer at the Joint Mathematics Meetings in Atlanta, Georgia. In 2007 the Association for Women in Mathematics and the Society for Industrial and Applied Mathematics selected Young to give the Sonia Kovalevsky Lecture at the 2007 SIAM Conference on Applications of Dynamical Systems held at the end of May in Snowbird, Utah. The Press Release states:-

The Kovalevsky Lecture recognizes her fundamental contributions in the field of ergodic theory and dynamical systems. Her pioneering research has had a significant impact in the investigation of dynamical complexity, strange attractors and probabilistic laws of chaotic systems. Her interests include theory, applications and deep connections to mathematical physics and probability. She is an inspiration to the entire mathematics community, especially to the women's mathematics community.
Barbara Keyfitz, Past President of the Association for Women in Mathematics, said that:-
... with the choice of Lai-Sang Young to give the Kovalevsky lecture within two years of her Noether lecture, two independent selection committees have recognized the importance of Young's work.
Cathy Kessel, President of the Association for Women in Mathematics, commented that:-
... the award is especially appropriate - Young is a very distinguished mathematician and her research extends the field in which Kovalevsky did her most significant work.

Article by: J J O'Connor and E F Robertson

September 2009
MacTutor History of Mathematics
[http://www-history.mcs.st-andrews.ac.uk/Biographies/Young_Lai-Sang.html]
Search All Ebay* AU* AT* BE* CA* FR* DE* IN* IE* IT* MY* NL* PL* SG* ES* CH* UK*
ELVIRA Mistress of the Dark hardcover book Cassandra Peterson SEALED NEW COPY

$37.48
End Date: Monday Aug-20-2018 7:25:25 PDT
Buy It Now for only: $37.48
|
Blue Book of Gun Values 2018 2019 39th Edition

$24.00
End Date: Wednesday Sep-12-2018 19:52:49 PDT
Buy It Now for only: $24.00
|
Confederate Flag 49”x49”

$13.79
End Date: Tuesday Aug-28-2018 5:21:11 PDT
Buy It Now for only: $13.79
|
Astrophysics for People in a Hurry by Neil deGrasse Tyson (Physics) [Hardcover]

$28.99
End Date: Saturday Aug-25-2018 6:51:54 PDT
Buy It Now for only: $28.99
|
Biblia Mediana, pasta NEGRA, Reina Valera 1960, LETRA GRANDE, pasta Vinil #01

$10.08
End Date: Wednesday Aug-15-2018 13:28:17 PDT
Buy It Now for only: $10.08
|
Deadly Skills : The SEAL Operative's Guide to Eluding Pursuers, Evading Capture,

$3.00
End Date: Monday Aug-27-2018 8:36:36 PDT
Buy It Now for only: $3.00
|
Between the World and Me by Ta-Nehisi Coates / digital eb00k **eb00k

$9.89
End Date: Tuesday Sep-11-2018 18:28:20 PDT
Buy It Now for only: $9.89
|
The Business of the 21st Century Paperback Rich Dad Robert T. Kiyosaki

$19.95
End Date: Wednesday Sep-12-2018 8:20:46 PDT
Buy It Now for only: $19.95
|
Children and young people’s workforce level 3 Book and cd

$5.88 (0 Bids)
End Date: Aug-19 05:03
|
Young Living Essential Oils Dragon Time 5ml Authentic and New

$0.99 (1 Bids)
End Date: Aug-17 13:30
|
Trolley COVERI you young,, Hand Luggage

$34.13
End Date: Aug-16 13:23
Buy It Now for only: US $34.13
Buy it now |
Hoya young house plant or cutting

$10.21
End Date: Sep-11 11:55
Buy It Now for only: US $10.21
Buy it now |
1Pcs KPOP NCT 2018 Empathy Official Photocard Dream Ver. Reality Select Members

$0.76
End Date: Aug-21 03:15
Buy It Now for only: US $0.76
Buy it now |
Teenage Underwear For Girls Children Young Training Bra For Kids Teens Puberty

$1.39
End Date: Sep-11 01:45
Buy It Now for only: US $1.39
Buy it now |
BTS Bangtan Boys Collective Photo Card LOVE YOURSELF WINGS YOUNG FOREVER

$1.89
End Date: Sep-04 12:19
Buy It Now for only: US $1.89
Buy it now |
Universal Phone Pop Up Holder Expanding Stand Grip Mount For Tablet Smartphone

$1.63
End Date: Aug-21 10:52
Buy It Now for only: US $1.63
Buy it now |

THE SLENDER COLLECTION The premium weight loss package- Now only $98

Start: 07 Nov 2017 | End: 07 Apr 2018

Save 15% off .com domain names at Heart Internet with AFFCOM15 at checkout.

Code: AFFCOM15

Start: 02 Oct 2017 | End: 30 Apr 2018

Save Up to 40% Off Budget-Friendly Used Tires at BestUsedTires.com!

Start: 03 Oct 2017 | End: 30 Apr 2018

Search All Amazon* UK* DE* FR* JP* CA* CN* IT* ES* IN* BR* MX
Booking.com B.V. is based in Amsterdam in the Netherlands. Ready for some statistics? Our 1,534,024 properties, including 860,482 holiday rentals, are located in 123,105 destinations in 229 countries and territories, and are supported internationally by 198 offices in 70 countries.
2013 Copyright © Techhap.com Mobile version 2015 | PeterLife & company
Skimlinks helps publishers monetize editorial content through automated affiliate links for products. Affiliate programm.
Terms of use Link at is mandatory if site materials are using fully or particulary.
Were treated to the site administrator, a cup of coffee *https://paypal.me/peterlife
Yandex.ru