Bengaluru: Joy Thomas, 57, a Google data scientist renowned for his work in information theory, passed away on September 28. Arogyaswami Paulraj, a US National Inventors Hall of Fame inductee, described Thomas as “the most brilliant gift from India to the US in engineering sciences in recent decades.”

Thomas grew up in Bengaluru, studied at St Joseph’s Boys High School, topped IIT-JEE in 1979, joined IIT Madras, and went on to do PhD at Stanford, where he did seminal work in information theory.

In a tribute to Thomas in IndiaTechonline.com and the US publication Indicanews, Paulraj wrote that Thomas’s “great contribution to engineering came from collaborating with Prof Tom Cover, a legend in information theory, to write a definitive textbook” on the subject.

“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 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 tens of thousands of PhD students have learnt information theory from his book,” he wrote. Information theory is today the basis for understanding every type of communication network – wireless, optical, and wired.

Thomas came to be in Google when a startup he co-founded in 2011, InsightsOne, was acquired by Apigee in 2014, and which in turn was acquired by Google two years later. Prior to InsightsOne, he co-founded a company called Stratify, which was later acquired by Iron Mountain.

Thomas’s brilliance was visible to everyone who knew him from his school days. Vijay Sundaram, a family friend, a junior to Thomas in IIT Madras and now the chief strategy officer at Zoho Corp, says his “earliest memory of Joy was the annual ritual of him winning every academic prize – General Proficiency, Science, Mathematics, Geography, History, Civics, English Language, English Literature – the young boy appearing embarrassed during the prize ceremony each year to be nabbing all the prizes but one (the Hindi language prize eluded him) and needing the student winning the Hindi prize to help him carry all those books he had won.”

But almost everyone who knew him also saw in him a remarkably sensitive and humble soul. In a tribute, Shyam Pillalamarri, friend, IITM & Stanford batchmate and former CTO of Samsung’s IT arm SDS, wrote: “With your brilliance of mind, kindness of heart and purity of soul, you were the perfect human being. The only fault that you ever had was that you were too good – too loving, too caring, and too giving.”

Akshay Bellare, IITM batchmate and president of Honeywell India, told TOI that nobody can ever forget Thomas. “He was 16 when he joined IITM. He was absolutely brilliant. At the time, the IITs used to take a test that allowed anyone who scored very well to skip the first year at IIT and go straight to the second year. Thomas took that test and was found eligible to skip the first year, but he chose not to use the option. And he was such a humble guy, so generous with his knowledge, sharing his notes, ideas. 300 of us have pledged to live the rest of our lives with Joy in mind,” Bellare says.

Mani Iyer, friend, IITM classmate and now CEO of Kwanzoo, recollected during a discussion with Thomas in an event organised by IIT Palakkad that during their days at IITM, while most would stay awake till 1.30 – 2 at night to prepare for tests and quizzes, Thomas’s lights would be off by 9.30-10pm. And the next day Thomas would ace the exam or quiz. “I’ve known Joy for 40+ years. He makes you feel like the most special person in the room, on the hike, at an event. Joy was a big part of who we are today. He was the moral core of our batch,” Iyer says.

Pandu Nayak, friend, colleague at Stanford, Stratify, and Google Fellow, described Thomas as one of the most remarkable people he has known. “Not only was he the smartest person, he was the kindest, gentlest, and most caring human being I knew!”

Ananth Jhingran, friend, fellow Stanford PhD, and former CTO of Google/Apigee, said he has incredible memories over 30 years. “I have seen his incredible smarts and humbleness at work. The Joy of cooking, of living, of mentoring, or teaching, of smiling is no longer with us. We are all better off because Joy chose to walk among us, and for that we are eternally grateful,” he said.

Shivvy aka Farex, friend, IITM classmate and now principal engineer at , wrote that it was a constant pleasure every year to receive Thomas’s New Year photo-greetings in the mail. “He was always the first to wish us every year. No affectionate wishes from Joy waiting for us in the mailbox anymore. Melancholy just tipped over into grief,” he wrote.

When Thomas was in IIT, he communicated with Cover expressing his desire to work with the latter for his PhD. Thomas later told friends later with some amusement that Cover appeared to view that communication as similar to those between legendary mathematician Srinivasa Ramanujan and Cambridge University’s Professor Hardy in 1913. Thomas became Cover’s first Indian graduate student. When Thomas was in the third year of the graduate programme, Cover approached him with a unique proposition – co-author a book on information theory. Thomas noted in the memorial for Cover in 2012 that this “was an opportunity of a lifetime…it was the best thing that has ever happened to me.” The two embarked on a two-year collaboration as co-authors of the seminal book in their field.

Abbas El Gamal, Thomas’s senior in Stanford and now professor of at the same university, said, “Without Joy the (book on the) elements of information theory would have never been written. It was Joy who ultimately made it happen for the benefit of many tens of thousands of students and researchers.”

Thomas’s time at Stanford was followed by groundbreaking research work at for over 10 years. At IBM, Thomas made key contributions in several areas, from speech recognition, to data mining, systems analysis and data compression algorithms.

Dilip Keshu, a classmate of Thomas from St Joseph’s Boys High School and now CEO of BORN Group, noted in his tribute to Thomas: “After hearing numerous stories of Joy’s genius from me, my son went up to him once and said, “My dad says you are a genius. just how bright are you? Do you know EVERYTHING?” And Joy calmly replied, “Your dad is brighter than I am.” Clearly, one heck of a lie but what a lovely thing to say to a kid.”

Thomas is survived by his wife Priya, son Joshua, daughter Leah, brothers Jose and Tony, and sister Mary.