Obituary: Dr Joy Thomas, information-theory stalwart


Arogayswami Paulraj is Professor Emeritus, Stanford University. 


Dr. Joy Thomas, a noted expert in Information Theory, died on Sept. 28, 2020, after a brief illness.

Joy was a legend during his student days in India. First All India Rank in the IIT Joint Entrance Exam and a perfect score in GRE (Graduate Record Examination – Global entrance exam for US Universities). He then joined Stanford University in 1984 for his Ph.D. and worked with Prof. Tom Cover as his advisor.

Joy’s great contribution to engineering came from collaborating with Prof. Tom Cover, a legend in Information Theory, to write a definitive textbook on this important, though abstract, subject.  Information theory studies the quantification, storage, and communication of information. It was originally proposed by Claude Shannon in 1948 to find fundamental limits on signal processing and communication operations such as data compression, in a landmark paper titled “A Mathematical Theory of Communication”. It is now the basis for understanding every type of communication network from wireless, optical, and wired.

Prof. Cover, the best name in the world in this area had waited decades for a partner with Joy’s level of genius to be his collaborator. And their book ‘Elements of Information Theory’, now in the second edition, remains the most popular and admired textbook on this subject around the world. There is no good academic bookstore in the world without Joy’s book. And 10,000s of Ph.D. students have learned Information Theory from his book.

Joy’s loss is mourned by all the giants in Information Theory around the globe, from Stanford, MIT, Princeton, Berkeley, and ETH Zurich to mention a few. He will certainly be greatly missed by the Information Theory research community.

After Stanford, Joy joined IBM Research and later did two successful startups in the Silicon Valley – Stratify and InsightsOne, and worked, till his passing, as a Data Scientist at Google.

Joy was perhaps the most brilliant gift from India to the US in engineering sciences in recent decades

Joy Thomas is survived by wife Priya and their two children Joshua and Leah.