Subhajit Barman

Hi!

I am Subhajit Barman, and welcome to my webpage. I am currently a National-Post Doctoral Fellow ( N-PDF ) at the Department of Physics of Indian Institute of Technology Madras ( IIT Madras ).

Two of the most important discoveries of modern physics are Einstein’s general theory of relativity ( GTR ) and quantum field theory ( QFT ). In GTR, time also has a coordinate status; thus, the notion of space-time was coined. The main idea of GTR is conveyed through the famous description by John Wheeler: Space-time tells matter how to move; matter tells space-time how to … curve. On the other hand, QFT combines the concepts of classical field theory, special relativity, and quantum mechanics to describe the physical dynamics of subatomic particles. There the development of gauge theory showed that all the standard model particles or forces could be incorporated into single field theory. However, the most puzzling quest that remains to be accomplished is how to combine the concepts of QFT with GTR, which leads to the topic of quantum gravity. The search for a proper quantum theory of gravity also stems from the urge to understand the high energy characteristics of quantum fields, which again is connected to the short-distance constitution of space-time. In this regard, many non-perturbative approaches like string theory and loop quantum gravity exist. There are also many successful perturbative approaches like effective field theories. These perturbative approaches consist of the quantum field theory in classical curved space-times, also known as semi-classical gravity. My research is mostly focused on the area of this semi-classical gravity.

Research Interest

At present, I am interested in understanding how different quantum aspects of particles, e.g., quantum entanglement, are generally affected by curvature. It also opens up other avenues of query, like whether we can distinguish different curved backgrounds by studying these effects and what quantum signatures of the relevant space-time we can infer.

My research interest also lies in studying different entanglement measures and providing observable predictions in contemporary, relevant scenarios. One of these scenarios is the Gravitational-wave background, where researchers are expected to receive more data and understandings in the coming years. Some theoretical predictions, like gravitational memory, are also expected to be identified through the coming space-based detector ( LISA ), where quantum entanglement will play a significant role. Quantum effects are believed to play a significant role in cosmological scenarios, e.g., in the cosmic microwave background ( CMB ) anisotropy, and my interest also lies in understanding its various aspects.

I am also interested in more theoretical consequences of utilizing QFT in curved space-times, like the Hawking effect, the black hole information loss paradox, and the Unruh effect.

List of Publications

My list of publications in Google Scholar, Inspire HEP.

National-Post Doctoral Fellow

2023 - Current

Department of Physics, IIT Madras, India
Mentor: Prof. Dawood Kothawala

Post Doctoral Fellow

2020 - 2022

Department of Physics, Indian Institute of Technology Guwahati ( IIT Guwahati ), India
Mentor: Prof. Bibhas Ranjan Majhi

Junior Research Fellow

2014 - 2020

Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata ( IISER Kolkata ), India
Thesis Advisor: Prof. Golam Mortusa Hossain

Cleared the Joint CSIR-UGC Test for Junior Research Fellowship and Eligibility for Lectureship ( NET ) held on June 21, 2015.

Awarded the Institute Postdoctoral Fellowship by IIT Guwahati in the Department of Physics on March 06, 2020.

International Travel Support ( ITS ) by the Science and Engineering Research Board ( SERB ) of India to attend the international conference “Avenues of Quantum Field Theory in Curved Spacetime” in Italy (September 14, 2022 to September 16, 2022).

Awarded the National Postdoctoral Fellowship by the Science and Engineering Research Board ( SERB ) of India on November 01, 2022.

Bachelor of Science in Physics from the University of Kalyani, India

2009 - 2012

Master of Science in Physics from IISER Kolkata

2012 - 2014

Doctor of Philosophy in Physics from IISER Kolkata

2014 - 2020

Thesis Advisor: Prof. Golam Mortusa Hossain

Thesis Title: Aspects of black hole physics in different quantum field theories.

I believe one has to have a private life to talk about personal stuff. For a Ph.D. scholar and then if one pursues postdoctoral research, there is little scope for a personal life. Therefore, this section remains redundant for me, at least for now.

Languages

Bengali ( বাংলা ) is my native language.

English ( speak & write ), Hindi ( speak ).

Skills

Mathematica, MATLAB, LaTeX, gnuplot, Python.

My Interests

My interests include music, football ( not the American one ), painting, and books.