Rouben V. Ambartzumian (Armenian: Ռուբեն Վ․ Համբարձումյան;Russian: Рубен В. Амбарцумян) (born 1941) is an Armenian mathematician and Academician of National Academy of Sciences of Armenia. He works in Stochastic Geometry and Integral Geometry where he created a new branch, combinatorial integral geometry. The subject of combinatorial integral geometry received support from mathematicians K. Krickeberg and D. G. Kendall at the 1976 Sevan Symposium (Armenia) which was sponsored by Royal Society of London and The London Mathematical Society. In the framework of the later theory he solved a number of classical problems in particular the solution to the Buffon Sylvester problem as well as the Hilbert's fourth problem in 1976. He is a holder of the Rollo Davidson Prize of Cambridge University of