• Tata Institute of Fundamental Research, Scanner, Bubble Chamber Group, 1970.
  • Centre for Advanced Study in Mathematics, Bombay (courses at TIFR), UGC Junior Research Fellow, 1975-76.
  • Indian Institute of Technology, Delhi, Junior Research Fellow, 1976.
  • Indian Statistical Institute, Delhi and Calcutta, Junior/Senior Research Fellow, 1976-81.
  • University of Poona, Departments of Mathematics and Statistics, Lecturer, 1981-88.
  • Indian Institute of Science, Bangalore, Senior Scientific Officer, 1988 (declined).
  • C-DAC (Centre for Development of Advanced Computing), Pune and Delhi, Member Technical Staff 1988-95. As head of initial Application Development Group, played a lead role in building the first Indian supercomputer PARAM.
  • Indian Institute of Advanced Study, Shimla, Fellow, 1991-93. Wrote a book: Time: Towards a Consistent Theory, Kluwer Academic, Dordrecht, 1994.
  • National Institute of Science, Technology, and Development Studies, Delhi, Fellow, 1995-98. Started writing a book: The Eleven Pictures of Time, Sage 2003.
  • Indian National Science Academy, Project Coordinator, 1998-2002. Project on "Madhava and the Origin of the Calculus".
  • Nehru Memorial Museum and Library, Affiliated Fellow, 1999-2002.
  • Centre for Studies in Civilizations, New Delhi, Editorial Fellow, Project of History of Indian Science, Philosophy, and Culture, 1999-2007. Authored a volume,: Cultural Foundations of Mathematics, Pearson Longman, 2007.
  • Integrated Academy of Management and Technology, Delhi NCR (Ghaziabad), Director (Academic), and Professor & Head (Information Technology), Feb 2000-Jan 2001.
  • National University of Journalism, Bhopal, Professor & Head, Centre for Computer Science, Feb 2001-06
  • Confederation of Indian Industry---Technology Development Board, Transfer of Technology Network, Centre Director for MCRPV Centre, 2003-06.
  • Inmantec, Delhi NCR (Ghaziabad), Distinguished Professor, and Director (Academic) 2007-


  • B.Sc. (Hons), Physics, 1973, Institute of Science, University of Bombay.
  • M.Sc., Mathematics, 1975, Centre for Advanced Study in Mathematics, University of Bombay.
  • Ph.D., 1980, Indian Statistical Institute, Calcutta.


  • Founder Member, Indian Society for Industrial and Applicable Mathematics.
  • Life Member, Computer Society of India.
  • Life Member, Indian Association for General Relativity and Gravitation.
  • Member, International Society for the Study of Time.
  • Member of the Editorial Board, Journal of Indian Council of Philosophical Research, 1998-2001.
  • Advisory Board, Encyclopaedia of Non-Western Science and Technology, Kluwer/Springer.
  • Listed in Marquis International Who's Who in Science and Technology, Dictionary of International Biography, etc.