Arshak Hajian, a distinguished Armenian-American mathematician and devoted advocate of Armenian mathematics, passed away on June 6 at the age of 95.
Born in 1930 in Cairo, Egypt, Hajian developed an early interest in mathematics during his college years. In the early 1950s, he continued his education in the United States, studying at the University of Pennsylvania and later at the University of Chicago.
He began his research career under the supervision of one of the leading mathematicians of the time, Shizuo Kakutani, with whom his scientific work remained closely connected throughout his career. Under Kakutani's guidance, Hajian was drawn into foundational work in ergodic theory connected to the work of Eberhard Hopf. Focusing on infinite-dimensional spaces, he went on to become one of the field's leading specialists.
Together with Kakutani, he developed a series of measure-preserving transformations that revealed distinctive properties of ergodic transformations in infinite-dimensional spaces. One of the most well-known of these constructions is now referred to as the Hajian–Kakutani transformation.
Hajian spent much of his academic career at Northeastern University in Boston and retired at the age of eighty.
Deeply committed to his homeland, he devoted much of his life to supporting Armenia and advancing Armenian mathematics. Even during the Soviet period, he visited Armenia several times, including the Institute of Mathematics of the National Academy of Sciences, and established connections with Armenian mathematicians. His engagement significantly expanded after Armenia's independence.
In the difficult years of the 1990s, he played an active role in helping sustain mathematical research in Armenia. Overcoming significant bureaucratic obstacles, he organized the delivery of components for early personal computers to the Institute of Mathematics and assembled them in unheated rooms, continuing this effort for several years.
At his initiative and with his personal funding, the Research Mathematics Foundation was established in 1998. The foundation played a key role in ensuring continuity in Armenian mathematical research by providing scholarships to top students at the Faculty of Mathematics of Yerevan State University, supporting research travel for Armenian mathematicians, hosting foreign scholars, and assisting in the organization of international conferences. With its support, the Institute of Mathematics of the National Academy of Sciences of the Republic of Armenia was renovated, and the first computer lab at the Faculty of Mathematics was established. The foundation remains active today, continuing to contribute to the development of mathematics in Armenia.
Even in his later years, Hajian remained highly active, visiting Yerevan several times a year, participating in conferences, and closely following the work of the foundation.
An eminent mathematician, devoted patriot, philanthropist, and foreign member of the NAS RA, Arshak Hajian's memory will remain vivid and enduring.
Faculty of Mathematics and Mechanics
