Prof Ratnavelu obtained his BSc (First Class Hons) and his MSc by research from the Department of Mathematics, University Malaya and furthered his PhD study in Atomic Physics at Flinders University in 1985 with a Flinders Research Scholarship. He started as a Lecturer in 1989; was promoted to Associate Professor in 1994 and subsequently as Professor in 2001. Prof Ratnavelu’s research and academic achievements has been recognized and he was awarded the Malaysian Toray Science Foundation Science & Technology Award in 2004 and also the Young Scientist Award (Strategic Sector) in 1996 by MOSTE. He was elected as a Fellow of the Academy of Sciences Malaysia in 2005. In 2006, he was awarded the Inaugural Distinguished Alumni Award by Flinders University.

His main research interest is in Theoretical Atomic Collision Processes with specific interest in positron collisions with atoms.  His outstanding contributions are in the recent development and the demonstration of an optical potential method to positron-hydrogen atom scattering process and its extension to other hydrogenic-type atoms. Another major contribution is his joint theoretical work with Jim Mitroy on anti-hydrogen formation in 1995. His scientific contribution’s is evidenced by his international publications; as a reviewer for international journals and his collaboration with eminent international researchers.

He has contributed to the scientific community in Malaysia as the Associate Editor of the Jurnal Fizik Malaysia (the leading physics journal in Malaysia) and the Associate Editor of Malaysia Journal of Science (one of the oldest journal in Malaysia). He has immensely helped in the professional development of Physics and Mathematics in Malaysia since the 1990’s in his capacity as the Honorary Secretary of the Institut Fizik Malaysia (1996-now) and Malaysian Mathematical Society (PERSAMA) respectively.

At University of Malaya, he has served as a Deputy Dean of Science (2003-2006) and acting Deputy Dean (1999-2000).