1. Hagen Kleinert was born on 15 June 1941 and is professor of theoretical physics at the Free University of Berlin, Germany, Honorary Doctor at the West University of Timisoara, and at the Kyrgyz-Russian Slavic University in Bishkek.

1. Hagen Kleinert was born on 15 June 1941 and is professor of theoretical physics at the Free University of Berlin, Germany, Honorary Doctor at the West University of Timisoara, and at the Kyrgyz-Russian Slavic University in Bishkek.
Hagen Kleinert is Honorary Member of the Russian Academy of Creative Endeavors.
Hagen Kleinert is married to Dr Annemarie Kleinert since 1974 with whom he has a son Michael Kleinert.
Hagen Kleinert has written several books on theoretical physics, the most notable of which, Path Integrals in Quantum Mechanics, Statistics, Polymer Physics, and Financial Markets, has been published in five editions since 1990 and has received enthusiastic reviews.
Hagen Kleinert studied physics at the Leibniz University Hannover between 1960 and 1963, and at several American universities including Georgia Institute of Technology, where he learned general relativity as a graduate student from George Gamow, one of the fathers of the Big Bang theory.
Hagen Kleinert earned his doctorate in 1967 at the University of Colorado, Boulder.
Later, Hagen Kleinert was to collaborate with Feynman in some of the latter's last work.
Landau for phase transitions which Hagen Kleinert developed in the books on Gauge Fields in Condensed Matter.
Together with A Chervyakov, Kleinert developed an extension of the theory of distributions from linear spaces to semigroups by defining their products uniquely.
Hagen Kleinert is a senior member of the faculty for the International Relativistic Astrophysics PhD Archived 6 July 2007 at the Wayback Machine Project, which forms part of the international network for astrophysics.
Hagen Kleinert was involved in the European Science Foundation's project Cosmology in the Laboratory.