Indiana University Purdue University Indianapolis

Professor Helps Students Exercise Mental Muscles in Classroom and Lab

Yogesh Joglekar, Ph.D.
Assistant Professor , Physics, School of Science

When most people think of theoretical physics they think of impossibly advanced mathematical calculations or perhaps Albert Einstein, Richard Feynman or Stephen Hawking, the Holy Trinity of 20th century physics.

Complex mathematical modeling is the bread and butter of what Yogesh Joglekar Ph.D., an assistant professor of physics at the School of Science at IUPUI, does daily, and he cites the quotable Feynman with frequency. But unlike most people, when Joglekar thinks about theoretical physics, he also thinks about undergraduates and high school students and how they can contribute to a field usually considered the purview of only the most advanced and brilliant minds.

Yogesh Joglekar, Assistant Professor of Physics, with Physics StudentsJoglekar teaches graduate and introductory undergraduate courses in mechanics, electricity, magnetism, and light. All of these provide opportunities for him to demonstrate how physics is at work everywhere and to engage students in the physical world in which they find themselves.

“I like to pose problems in class and get students thinking. That “ah ha” moment, when they understand how and why something happens -- how the skin detects heat, why light bends in a certain way when passing from air into glass - is wonderful for them as they flex their analytical muscles. It’s wonderful for me, too, as I see the students respond to science which is conceptually difficult but ultimately basic,” said Joglekar, who was the recipient of a 2009 Indiana University Trustee’s Teaching Award.

As a research mentor he reaches out to both undergraduates and high-school students. “Although theoretical physics research has traditionally been beyond the capability of beginning physics students and usually not tackled until the graduate level, the advent of new mathematical computing software with good user interfaces has enabled bright high school and undergraduate students to carry out original research,” said Joglekar, who has been on the School of Science faculty since December 2005.

In the summer of 2010 Joglekar and high school student Mark Babbey studied the properties of quantum particles that hop from site to site on a chain in which one site can absorb them and another can emit them, technically known as a PT-symmetric chain. Joglekar uses a simplified analogy of a canal to explain their research. A canal without tributaries has a constant flow of water. If a canal has one tributary carrying water in and one distributary carrying water out, the water flow in the canal will depend upon the distance between them and their sizes. With Babbey’s assistance on the mathematical facets of the problem, Joglekar is looking for the critical values of the tributary size and distance, below which the new system (a canal with a tributary and distributary) functions as the old one (just a canal).

Babbey’s work with Joglekar was made possible by a grant from the D. J. Angus-Scientech Educational Foundation. This Indianapolis-based organization, which focuses on encouraging Indiana youth to study in scientific and technological fields, has made it possible for high school students to work with Joglekar and other faculty in the School of Science’s physics department each summer.

With only a high-school level mathematical background, Babbey developed a MATLAB code under Joglekar’s mentorship. Together they came up with a wide “U” shaped phase-diagram that, in the canal analogy, showed the relation between the constant-flow region and the distance between the tributary and the distributary. This diagram spurred further interest in and enabled theoretical analysis of the PT-symmetric chain problem.

“We constructed a new model with properties that had not been previously explored. Although we didn’t do this with a practical application in mind, possible application might include novel optical or electrical devices,” said Joglekar. “Going back to the canal analogy, and to oversimplify, we were not just measuring water flow, we were also measuring a variety of flow characteristics such as the water velocities at the inlet and outlet.

Recently their paper, “Robust and Fragile PT-symmetric Phases in a Tight-binding Chain,” on which physics graduate student Derek Scott is also a co-author along with a Los Alamos National Laboratory physicist, was published in Physical Review A, a top tier peer-reviewed scientific journal and selected for rapid communication due to its importance to the field.

“Although I only had one year of high-school physics and had to learn a lot of math on the fly over the summer to do the work, it was an amazing experience and I couldn’t have asked for a better opportunity. Working in a real lab, on a real project that had never been attempted before, sparked my interest. This wasn’t a textbook lab exercise that every other physics student had done before; this was research. Both Derek Scott, who helped me understand the math and checked my work, and Dr. Joglekar, who patiently explained to me the concepts and the importance of what we were doing, were great mentors,” said Babbey, a senior at Guerin Catholic High School in Noblesville, Ind., who says that both physics and chemistry are strong contenders for his future college major prior to a possible law career.  

“It is extremely rare for a high school student to be a co-author on a physics paper. Statistics on this aren’t available, but it is likely less than 1 paper in 1,000, that’s one tenth of one percent of physics research papers, has a high school co-author. It is unusual even for upper class undergraduates to publish in physics. This is usually the province of graduate students and faculty,” commented Andrew Gavrin, Ph.D., chairman of the School of Science’s Department of Physics.

“Science is everywhere – from the side-mirror on a car which says “objects in the mirror are closer than they appear” to the cell phone and computers we all take for granted. In real life, there will be no book to tell our students whether they have the right answers to problems they confront. That’s why we don’t teach by asking them to check their work in answer keys at the back of the book.  We want them to exercise their mental muscles in the classroom and the lab,” said Joglekar.