Tudor Stefan Rațiu (born March 18, 1950 in

Timișoara ), City of Roses ( ro, Orașul florilor), City of Parks ( ro, Orașul parcurilor) , image_map = Timisoara jud Timis.svg , map_caption = Location in Timiș County , pushpin_map = Romania#Europe , pushpin_ ...

) is a

Romania Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, S ...

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

who has made contributions to

geometric mechanics Geometric mechanics is a branch of mathematics applying particular geometric methods to many areas of mechanics, from mechanics of particles and rigid bodies to fluid mechanics to control theory. Geometric mechanics applies principally to systems f ...

and

dynamical systems theory Dynamical systems theory is an area of mathematics used to describe the behavior of complex dynamical systems, usually by employing differential equations or difference equations. When differential equations are employed, the theory is called ' ...

Education

His father, Mircea Ratiu, an engineer, was the younger brother of

Ion Rațiu Ion Rațiu (; 6 June 1917 – 17 January 2000) was a Romanian lawyer, diplomat, journalist, businessman, writer, and politician as well as the official presidential candidate of the Christian Democratic National Peasants' Party (PNȚ-CD) in the ...

, a well-known Romanian politician, while his mother, Rodica Bucur, was a piano professor at the Conservatory of Music in Timișoara. Ratiu did his undergraduate studies at the University of Timișoara, completing his

B.Sc. A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years. The first university to admit a student to the degree of Bachelor of Science was the University of ...

in 1973 and his

M.S. A Master of Science ( la, Magisterii Scientiae; abbreviated MS, M.S., MSc, M.Sc., SM, S.M., ScM or Sc.M.) is a master's degree in the field of science awarded by universities in many countries or a person holding such a degree. In contrast to ...

in 1974. After moving to the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, he completed his

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

degree at the

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...

in 1980; his dissertation, written under the supervision of

Jerrold E. Marsden Jerrold Eldon Marsden (August 17, 1942 – September 21, 2010) was a Canadian mathematician. He was the Carl F. Braun Professor of Engineering and Control & Dynamical Systems at the California Institute of Technology.. Marsden is listed as an ISI ...

, was titled ''Euler-Poisson Equations on Lie Algebras''.

Career

From 1980 to 1983 he was a T. H. Hildebrandt Research Assistant Professor at the

University of Michigan , mottoeng = "Arts, Knowledge, Truth" , former_names = Catholepistemiad, or University of Michigania (1817–1821) , budget = $10.3 billion (2021) , endowment = $17 billion (2021)As o ...

, after which he became an Associate Professor of Mathematics at the

University of Arizona The University of Arizona (Arizona, U of A, UArizona, or UA) is a public land-grant research university in Tucson, Arizona. Founded in 1885 by the 13th Arizona Territorial Legislature, it was the first university in the Arizona Territory. T ...

. In 1987 he moved to the

University of California, Santa Cruz The University of California, Santa Cruz (UC Santa Cruz or UCSC) is a public university, public Land-grant university, land-grant research university in Santa Cruz, California. It is one of the ten campuses in the University of California syste ...

, where he became a Professor of Mathematics in 1988. In 1998 Ratiu moved to the

École Polytechnique Fédérale de Lausanne École may refer to: * an elementary school in the French educational stages normally followed by secondary education establishments (collège and lycée) * École (river), a tributary of the Seine flowing in région Île-de-France * École, Savoi ...

, where he was a professor until 2015. In 2014–15, he was a Professor of Mathematics at the

Skolkovo Institute of Science and Technology The Skolkovo Institute of Science and Technology, or Skoltech, is a private institute located in Moscow, Russia. Skoltech was established in 2011 as part of a multi-year partnership with the Massachusetts Institute of Technology (MIT) Globally ...

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

. Since 2016 he is a professor at

Shanghai Jiao Tong University Shanghai Jiao Tong University (SJTU; ) is a public research university in Shanghai, China. The university is funded by the Ministry of Education of China. The university was established on April 8, 1896 as Nanyang Public School (南洋� ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

. Ratiu received a

Sloan Research Fellowship The Sloan Research Fellowships are awarded annually by the Alfred P. Sloan Foundation since 1955 to "provide support and recognition to early-career scientists and scholars". This program is one of the oldest of its kind in the United States. ...

in 1980, and he became a fellow of the

American Mathematical Society The American Mathematical Society (AMS) is an association of professional mathematicians dedicated to the interests of mathematical research and scholarship, and serves the national and international community through its publications, meetings, ...

in 2012.

Publications

* * * * *

References

External links

* 1950 births Living people Scientists from Timișoara 20th-century Romanian mathematicians 21st-century Romanian mathematicians Politehnica University of Timișoara alumni University of California, Berkeley alumni University of Michigan faculty University of Arizona faculty University of California, Santa Cruz faculty Academic staff of the École Polytechnique Fédérale de Lausanne Academic staff of Shanghai Jiao Tong University Dynamical systems theorists Fellows of the American Mathematical Society Sloan Research Fellows {{US-mathematician-stub