Oded Regev (born 1946) is a physicist and astrophysicist, professor emeritus of the Technion, Israel Institute of Technology. He is best known for his theoretical application of

fluid dynamics In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids— liquids and gases. It has several subdisciplines, including ''aerodynamics'' (the study of air and other gases in motion) an ...

and

dynamical systems In mathematics, a dynamical system is a system in which a function describes the time dependence of a point in an ambient space. Examples include the mathematical models that describe the swinging of a clock pendulum, the flow of water in a p ...

theory to

astrophysics Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline said, Astrophysics "seeks to ascertain the nature of the h ...

Career

Regev was born in Poland and emigrated to Israel in 1958. His academic career was mainly in Israel. He studied physics and mathematics at the

Hebrew University of Jerusalem The Hebrew University of Jerusalem (HUJI; he, הַאוּנִיבֶרְסִיטָה הַעִבְרִית בִּירוּשָׁלַיִם) is a public research university based in Jerusalem, Israel. Co-founded by Albert Einstein and Dr. Chaim Weiz ...

, with graduate studies and a Ph.D. at

Tel Aviv University Tel Aviv University (TAU) ( he, אוּנִיבֶרְסִיטַת תֵּל אָבִיב, ''Universitat Tel Aviv'') is a public research university in Tel Aviv, Israel. With over 30,000 students, it is the largest university in the country. Locate ...

, and became a faculty member at the

Technion – Israel Institute of Technology The Technion – Israel Institute of Technology ( he, הטכניון – מכון טכנולוגי לישראל) is a public research university located in Haifa, Israel. Established in 1912 under the dominion of the Ottoman Empire, the Technion ...

. During his studies he served four years in the

Israel Defense Forces The Israel Defense Forces (IDF; he, צְבָא הַהֲגָנָה לְיִשְׂרָאֵל , ), alternatively referred to by the Hebrew-language acronym (), is the national military of the Israel, State of Israel. It consists of three servic ...

and continued to serve in the reserve units, reaching the rank of major. In 2002 he moved to the US.

Contributions

His early numerical calculations (with G. Shaviv) of a rotating gas sphere

gravitational collapse Gravitational collapse is the contraction of an astronomical object due to the influence of its own gravity, which tends to draw matter inward toward the center of gravity. Gravitational collapse is a fundamental mechanism for structure formatio ...

(1980) were the first to show that a central object (a star) is formed surrounded by a protoplanetary disk-like nebula, provided

turbulent In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between t ...

viscosity The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the inte ...

is included. Together with J.R. Buchler he found a simplistic model of a stellar oscillator that exhibited chaotic pulsation. This oscillator was later found to be related to the Moore-Spiegel oscillator. He was among the discoverers of the advection dominated

accretion Accretion may refer to: Science * Accretion (astrophysics), the formation of planets and other bodies by collection of material through gravity * Accretion (meteorology), the process by which water vapor in clouds forms water droplets around nucl ...

flows (ADAF) which became a very popular idea in modeling

accretion disks An accretion disk is a structure (often a circumstellar disk) formed by diffuse material in orbital motion around a massive central body. The central body is typically a star. Friction, uneven irradiance, magnetohydrodynamic effects, and other fo ...

around

black holes A black hole is a region of spacetime where gravity is so strong that nothing, including light or other electromagnetic waves, has enough energy to escape it. The theory of general relativity predicts that a sufficiently compact mass can def ...

. In his later years he concentrated on theory of accretion disks applying mathematical approximation methods that were novel to astrophysics. He investigated instabilities of accretion disks that may give rise to angular momentum transport, excluding the possibility that the magneto-rotational instability may develop beyond linear stage in thin, disks with very low magnetic

Prandtl number The Prandtl number (Pr) or Prandtl group is a dimensionless number, named after the German physicist Ludwig Prandtl, defined as the ratio of momentum diffusivity to thermal diffusivity. The Prandtl number is given as: : \mathrm = \frac = \frac ...

as such structures usually are.

Books

Regev is the author of : *''Physics with Answers: 500 Problems and Solutions'' (with Andrew R. King, Cambridge University Press, 1997) *''Chaos and Complexity in Astrophysics'' (Cambridge University Press, 2010) *''Asymptotic Approximation Methods in Astrophysical Fluid Dynamics: Techniques and Example Applications'' (with Orkan M. Umuthan, VDM Verlag, 2010) *''Modern Fluid Dynamics for Physics and Astrophysics'' (with Orkan M. Umurhan and Philip A. Yecko, Graduate Texts in Physics, Springer, 2016)Review of Modern Fluid Dynamics for Physics and Astrophysics: *

References

External links

Home page
* {{DEFAULTSORT:Regev, Oded 1946 births Living people Israeli astrophysicists Jewish physicists