Sayantani Lahiri
Ph.D., Jadavpur University and IACS KolkataSayantani Lahiri
Ph.D., Jadavpur University and IACS KolkataMy current research is driven by a fundamental question: how can our understanding of theoretical physics, together with state-of-the art computational methods help us uncover some of the most extreme phenomena in our Universe? My work lies at the intersection of gravitation, cosmology, and relativistic astrophysics, with a particular interest in understanding the physics of the early Universe and compact astrophysical objects.
One of my primary research interests is cosmological inflation—the period of rapid accelerated expansion believed to have taken place in the very early Universe. I study inflationary models within General Relativity as well as modified theories of gravity, with the aim of understanding the dynamics of the early Universe, the evolution of scalar fields, and the possible observational consequences. I am particularly interested in exploring how different theoretical frameworks can be tested through cosmological and gravitational-wave observations.
The other part of my research focuses on relativistic hydrodynamics and astrophysical black holes. I work on physics of accretion flows around black holes by studying the roles of various fluid properties including viscosity, macroscopic fluid-spin, magnetisation, etc. These studies allow us to und how these physical processes shape the structure and evolution of accreting systems and their potential observational signatures.
In recent years, I have also become increasingly interested in computational approaches, machine learning, and data science as tools for addressing problems in physics. These complementary approaches that can help us analyse complex physical systems, identify patterns in large datasets, and develop new ways of extracting information from observations.
Dr. Sayantani Lahiri is an Assistant Professor at Chanakya University, with a research background spanning theoretical physics, relativistic astrophysics and cosmology. She completed her Ph.D. in High-Energy Physics at Jadavpur University and Indian Association for Cultivation of Science, Kolkata. She subsequently held research positions at various universities in Germany including at ZARM, Universität Bremen, the Goethe University Frankfurt, and Julius-Maximilians-Universität Würzburg. She has contributed to research supported by two DFG-funded (German Research Foundation) projects on general-relativistic viscous and spin-fluid accretion disks and has collaborated with researchers working on black hole imaging and strong-gravity physics. Her work has been presented at international conferences and seminars across Europe and India. In 2023, she contributed an invited chapter to the Springer volume Gravity, Cosmology, and Astrophysics — A Journey of Exploration and Discovery with Female Pioneers. More recently, she has expanded her computational expertise through work in artificial intelligence and data science, bringing together theoretical physics with modern computational approaches.
- Ph.D., – 2015: Jadavpur University and IACS Kolkata. Thesis title: Signatures of extra spacetime dimensions.
- MSc., in Physics – 2007 : University of Calcutta
- B.Sc., in Physics (Honours) – 2005 : University of Calcutta
- Equilibrium models of Weyssenhoff spin fluid accretion tori around Kerr black holes.
Phys. Rev. D, 112(8):083037,2025.
Sergio Gimeno-Soler, Sayantani Lahiri, and Claus Laemmerzahl. - Stationary models of magnetized viscous tori around a Schwarzschild black hole.
Phys. Rev. D, 103 (4):044034, 2021.
Sayantani Lahiri, Sergio Gimeno-Soler, José A. Font, and Alejandro Mus Mejías. - Second order causal hydrodynamics in Eckart frame: using gradient expansion scheme.
Class. Quant. Grav., 37:075010, 2020.
Sayantani Lahiri. - Anisotropic inflation in Gauss-Bonnet gravity.
JCAP, 09:025, 2016.
Sayantani Lahiri. - Can extra dimensional effects allow wormholes without exotic matter?
Phys. Lett. B, 750:319–324, 2015.
Sayan Kar, Sayantani Lahiri, and Soumitra SenGupta.
- Conceptualised and developed Deutsche Forschungsgemeinschaft (DFG) grant proposals: “General-relativistic theory of viscous accretion disks around black holes” and “Spin fluid accretion disks”. Both the proposals got successful fundings by DFG respectively in 2017 and 2021.
- Served as a reviewer for journals including The Astrophysical Journal, General Relativity and Gravitation, European Physical Journal C, and Nuclear Physics B.