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Laboratory researcher tackles some of science’s hardest problems with computer programming

How Tanmoy Bhattacharya ‘talks nicely to the machine’
November 23, 2020
How Tanmoy Bhattacharya ‘talks nicely to the machine’

“Computers don’t create problems for me, they like me,” says Tanmoy Bhattacharya


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“Science is all about patterns — I try to arrange it by section so I can make connections.”- Tanmoy Bhattacharya

The patterns dotted on the punch cards catch Tanmoy Bhattacharya’s eye as he works in a laboratory in 1980s Kharagpur, near Calcutta, India.

Scattered across the paper, the clusters of tiny holes represent answers. The computer has all the knowledge. He just has to ask the right questions with the cards to get it — “talk nicely to the machine," as he likes to say.

Tanmoy’s mind begins to see the broader picture of how an IBM 1620 — a very early computer; loud, large and cumbersome with flashing lights and dials — thinks and works.

It will ultimately propel his career toward the pursuit of some of the most advanced science ever known.

“Once you know the difficulties of designing a language, the rules of the computer language are no longer arbitrary; rather they become ingrained,” Tanmoy says, thinking back on those years.

“Computers don’t create problems for me, they like me,” he says. “I ask them nicely for information and they give it to me.”

'Intellectual stamp collecting' — From punch cards to solving the HIV crisis

Decades later, Tanmoy, who works in the Laboratory’s nuclear and particle physics, astrophysics and cosmology group, helps maintain and program computers at Los Alamos that crunch complex data in order to design computational models for vaccines that can predict and possibly prevent HIV — one of the most enduring, complicated and devastating bloodborne diseases on the planet.

The work eventually contributes to the development of the world’s first computationally-generated vaccine sequences — including the HIV “mosaic” vaccine, which is one of only a handful of potential preventive measures to ever reach human efficacy trials.

The principal architect of the mosaic vaccine, Bette Korber, a Lab Fellow and Richard Feynman Award winner who was recently named R&D Magazine's "Scientist of the Year," says Tanmoy is "really good to have on a project, as he is very clear thinking, fast on his feet and spectacular at a whiteboard." She also lauds his "substantial contributions" to determining viral evolution and transmission and phenotype/genotype relations of HIV.

Paul Dotson, associate Laboratory director for Simulation and Computation, calls Tanmoy’s scientific prowess “amazing.”

“The more I’ve worked with Tanmoy, the more I realize the breadth of his talents and interests,” Dotson says. “I’ve yet to find a topic where he didn’t have an informed opinion.”

Just a few of Tanmoy's specialties:

  • Particle physics and physics of complex systems
  • Phylogenetics and emergence in evolutionary systems
  • Quantitative studies of linguistics and human behavior
  • Computer security and machine learning in the health sciences

He's also an aspiring historian, with a particular interest in his native country of India.

To Tanmoy, science and other disciplines present a puzzle of patterns that must simply be processed like punch cards on an IBM 1620 to understand.

“Science is all about patterns — I try to arrange it by section so I can make connections, and physics has been doing this exact same thing for a long time,” he says.

Explaining the impossible

tanmoy2.jpgTanmoy reduces challenges in science and other disciplines to a puzzle of patterns. Physics is Tanmoy's favorite subject of all.

In 2000, he and colleagues started to examine the emergence of classical physics from quantum mechanics, asking why — contrary to all the expected quantum fuzziness — everyday objects seem to have concrete attributes like position.

Using the supercomputers of the day, their work showed that when measurements are neither unbelievably strong nor weak, there is no way to tell the difference between the classical and quantum models.
“In other words, under ordinary conditions, the world looks both classical and quantum, but since the classical description needs less mental resources to work with, we have learned to think of it as classical,” Tanmoy says. “This body of work naturally led to the really interesting case when measurement is basically absent, so that quantum mechanics in its pure form flourishes.”

Collaboration = innovation

Tanmoy finds deep appreciation for the Lab’s openness to new ideas, collaborative spirit and innovation.

“LANL doesn’t give you boundaries — it’s a unique place. It’s very difficult to find that kind of freedom in most places,” he says. “Having a talent pool like this that wants to work together — it’s very unique. Collaborations are rampant.”