Professor Gul Agha’s distinguished career was honored with a two-day festschrift on October 6-7 in Chicago, where former and present colleagues and students spoke on the vast legacy he has built, as well as his continued work. Agha is a research professor and professor emeritus in the Siebel School of Computing and Data Science at The Grainger College of Engineering. He is renowned for his development of the Actor Model of Concurrency.

Agha's peers felt a festschrift, whose German origins literally translate to “celebration of writing,” was a proper way to celebrate Agha. It gave an opportunity to let him know how critical his work was to them and computer science.

Photo Credit: Gul Agha

“Maybe a festschrift is the right way to do a funeral. If you’re dead, you don’t know what people say about you,” Agha quipped. “People should have a funeral before they die.”

Jose Meseguer, Illinois professor of computer science, agreed. “It's like a family reunion where all of your close colleagues, students and other researchers come together as a choir or symphony or orchestra, so to speak, honoring the person,” Meseguer said.

“There’s scientific value in an event like this,” Meseguer added. “It’s a moment for articles and reflection that give you the vision of the long-term evolution of the ideas and impact of the ideas.”

“Gul’s visionary work helped shape the fields of concurrent computation, distributed systems and actor-based models,” said Mahesh Viswanathan, senior associate director of the Siebel School. “In the last forty years, his contributions are immeasurable. He is more than a researcher; he is a leader, a mentor and a friend to countless people who have had the honor of working with him.”

Photo Credit: Gul Agha

Viswanathan’s praise is echoed by anyone who has worked with Agha, including Meseguer.

“Gul is an exceptional person, as a scientist and a human,” he said. “He has a very deep understanding of humanity and of human beings. He has been a wonderful mentor to his students.”

MyungJoo Ham, master at AI Center at Samsung Research and former Illinois PhD student, found his own PhD research initially lacking the timely evolution he had hoped for. Agha, as his mentor, was there to guide and support him. “I feel incredibly fortunate to have had his guidance during my PhD,” Ham said. “What Gul demonstrated as a research team leader has been a significant influence on me.”

Photo Credit: Gul Agha

Another of Agha’s former PhD students, Youngmin Kwon, computer science associate professor at SUNY Korea, concurred. “He gave me freedom to choose my research topics and supported my choices as long as they were related to the research theme of the group.” He added his gratitude for Agha’s “continued support not only while I was in his group, but even after I graduated from Illinios.”

Agha was born in Sindh, Pakistan. An inquisitive young person, he was not excited by the education he was receiving there. “It gave me lots of time to think about nature, think about the universe; ask questions; ponder on questions. That was an interesting time,” he said.  “That was also the time I became vegetarian—later on vegan—because I got to know lots of animals individually.”

Photo Credit: Gul Agha

By the age of 14, after skipping a couple grades, he decided he wanted to study science. Realizing the limitations of study in Pakistan, he was determined to study abroad, though there were few options available to him given the high cost. At 16, he was accepted to Caltech, the first person from Pakistan to be admitted there.

Originally, Agha’s interest in science was broader. His first publication was in economics, specifically Intertemporal Speculation, which was later used by Vernon Smith, 2002 Nobel Memorial Prize winner in Economic Sciences, in his graduate seminar. Agha was also interested in neurobiology, but at the time, it required too much experimental work on animals.  He studied quantitative psychology at Michigan which got him interested in AI, specifically parallelism in AI, which led to his work at MIT.

Agha would get to MIT via his soon-to-be wife, Jennifer Cole, associate dean for faculty at Northwestern University, who attended the school to pursue linguistics. Though he hadn’t originally planned on going to MIT, he knew it would be a good spot to complete his own research. There he met Carl Hewitt, then-professor of electrical engineering and computer science.

Photo Credit: Gul Agha

“I paid a visit to him and convinced him to hire me,” Agha said. He finished his thesis research and stayed on to teach for a couple years. Because of Agha's interest in parallelism, he was working with John Holland, pioneer in genetic algorithms and then-professor of electrical engineering and computer science at the University of Michigan. That got Agha interested in problem parallelism.

After a brief stint at Yale, where he says it lacked a cultural fit, he made it to Illinois. Agha said that at that time, Illinois was free from politics, it was a top computer science department and it had the collegial atmosphere he craved.

“When Illinois made an offer, I decided it would be a great place to raise a family,” Agha said. He thought he would try it out for 5 years and then decide whether to return to the East Coast. He stayed a lot longer.

“That often happens to people who first look at Urbana-Champaign,” he joked.  

Photo Credit: Gul Agha

Soon after he arrived, he was the only faculty member working in formal methods and programming languages. He was able to build a strong group of faculty around formal methods, programming language and software by convincing his top choices to move to Urbana-Champaign. “It’s now one of the strongest groups I was involved in recruiting, virtually everybody there until the last few years,” he said.

Today, Agha’s work is the basis for large systems like Facebook messenger, Twitter (now X) and LinkedIn, to name a few.

“At first, large-scale parallelism was just a research paradigm that researchers followed, but it took off with a vengeance,” he said. “There was a delayed impact. There’s a kind of inevitability about it. If I hadn’t, somebody somewhere else would have down the line anyway.”

Many would stop after building such a legacy, but not Agha. He has recently been working in the area of energy consumption in information technology, particularly with the rise of AI and how to make it more energy efficient.

“Look at the brain of an insect—it’s much more energy efficient,” he said. “It takes such tiny amount of energy to do such complex tasks compared to what supercomputers and large-cloud computing frameworks are doing for AI.” Agha is interested in using parallelism not just for performance but for reduction of energy consumption.

Photo Credit: Gul Agha

His interest in energy consumption has opened his interest in quantum computing and how it reduces energy consumption while giving higher performance. Agha estimates that faulty software and security holes account for losses in the hundreds of billions of dollars a year.

 Of course, Agha’s work doesn’t stop when he gets home. After a move to Evanston, IL, he began a push on environmental initiatives.

“I convinced the mayor to appoint me to the environment board,” he said. “It’s always an uphill battle, even in a progressive city.”

He’s also the president of his condominium board. “It’s like being mayor of a small village,” he said. It was in this role that he discovered the excessive energy consumption in high-rise buildings. Agha is now advocating against high-rises and pushing for green technology. “Thirty-one percent of greenhouse gas emissions are high-rise buildings. Cars are 16 percent.”

As he discussed his passion for advocacy, Agha recalled his time as an activist at MIT where he convinced the city of Cambridge to pass an ordinance regulating research labs that used animal testing. Because of his work, Cambridge began inspecting species not covered by federal regulations to ensure certain conditions were met. A Harvard thesis was even written on the project. 

Photo Credit: Gul Agha

Four decades and one festschrift in, Agha doesn’t foresee slowing down on either his research or his activism pursuits, especially when the two intersect. In true Agha fashion, he pointed out the current political climate facing the world and, specifically, the next generation of computer scientists. 

“Now more than ever, there is an importance and value in academic freedom,” he said. “Institutions have a responsibility to society to allow free expression of ideas and even criticism of the institution itself.”

As Agha continues his tireless pursuits, his fans know that he'll eventually amass enough accomplishments to warrant a second festschrift. "I'm not sure when he rests," Viswanathan said. "Gul is a model of hard work, generosity and kindness." 

Grainger Engineering affiliations

Gul Agha is an Illinois Grainger research professor and professor emeritus of computer science in the Siebel School of Computing and Data Science. 

Mahesh Viswanathan is an Illinois Grainger professor of computer science in the Siebel School of Computing and Data Science. 

Jose Meseguer is an Illinois Grainger professor of computer science in the Siebel School of Computing and Data Science.