Raj Kumar Pathria

Pathria is also the author of a graduate textbook on statistical mechanics, whose fourth edition appeared in the year 2021. He also wrote a book on relativity that was published as a Dover edition in the year 2003.

Pathria is married to a former student of his, named Raj Kumari (nee Gulati). They were blessed with two daughters and a son, as well as five grandchildren; unfortunately, they lost their younger daughter to Cancer in 2011.

Pathria retired from the University of Waterloo in August 1998 and, soon thereafter, moved to the west coast of the US and became an adjunct professor of physics at the University of California at San Diego – a position he continued to hold till 2010. In 2009, Pathria's newest publishers (Elsevier/Academic) prevailed upon him to produce a third edition of this book. He now sought the help of Paul Beale, of the University of Colorado at Boulder, whose co-authorship resulted in another brand new edition in March 2011. Ten years later, in 2021, Pathria and Beale produced a fourth edition of this book.

Pathria's current hobbies are 'contemporary world affairs' and 'Urdu poetry'. Right from his childhood, Pathria was nurtured in an atmosphere replete with Urdu language, Urdu idiom and Urdu poetry. Having read and imbibed dozens of classics emanating from stalwarts like Mir, Ghalib, Zauq, Momin, Hali, Dagh and Iqbal, down to modernists like AsGhar, Fani, Hasrat, Jigar, Firaq and Faiz, Pathria finally turned to writing Urdu poetry himself – but only around the year 1993 when he was close to retirement from Physics.

In 1969 Pathria returned to Canada and, in addition to his other academic pursuits, continued to teach a variety of courses at the University of Waterloo and the University of Windsor. In 1972 the Pergammon Press, Oxford, published his classic text Statistical Mechanics, which became an instant success on the international scene. In the early 1990s, when his new publishers (Butterworth-Heinemann) persuaded Pathria to produce a second edition of this text, he sought the help of Surjit Singh, a former student of his from the Chandigarh days (who had also been a postdoctoral fellow with him at Waterloo during the years 1983–87). The result of this joint effort was a brand new edition of this book that came out in July 1996 and, like its predecessor, continued to be a bestseller.

Even though his field of research at the University of Delhi was primarily statistical mechanics, Pathria, during that time, got fascinated with the subject of relativity and in 1963, with the friendly cooperation of the Hindustan Publishing Corporation (India), produced a book entitled The Theory of Relativity. This maiden attempt at book-writing resulted in fabulous reviews from far and wide, especially from Professor William McCrea – who himself was a celebrated author on this subject. In 1974, the Pergamon Press, Oxford produced a second edition of that book and in 2003 Dover Publications of New York took that book under their wings. In Canada, Pathria continued his research in the diverse field of statistical mechanics; at the same time, he gave graduate courses on that subject at McMaster University, Hamilton and the University of Alberta, Edmonton. In 1967, he returned to India to take up professorship of theoretical physics at the Panjab University, Chandigarh, where (apart from conducting research in a variety of subjects in mathematical physics) he continued his mission of teaching the fundamentals of statistical mechanics.

Pathria obtained his BSc Honours and MSc Honours degrees from Panjab University, Hoshiarpur in July 1953 and July 1954, respectively, and soon thereafter, at the invitation of Professor F.C. Auluck, joined the graduate school of Physics at the University of Delhi for his doctoral studies – which he completed in March 1957. In February 1958, he joined the University of Delhi as a lecturer in physics and in April 1961 got promoted to readership. In August 1964, he left Delhi to take up a visiting professorship at McMaster University in Canada.

Pathria was born in a middle-class Punjabi family to parents Ramji Das Pathria and Mela Devi Pathria in a small town named Ramdas, 28 miles to the north of Amritsar. He received his early education in a local high school and then joined the Hindu College, Amritsar for his FSc studies. He was placed on the 'Role of Honour' of that college in the year 1950.

Raj Kumar Pathria (born March 30, 1933) is a theoretical physicist, a Distinguished Professor Emeritus at University of Waterloo, and an Urdu poet.