S. Shankaranarayanan

(Group leader)


Project students

Alumni

Research interests

Abhishek Basak


I am doing research in the field of cosmology. I am interested in the inflationary theory,dark energy with the non-standard spiors. Currently I am doing research on generation of seed magnetic field during the inflation. I am also interested in the study of attractor scenario in the various inflationary models and the reheating scenario in the inflationary models with non-minimal coupling.


Swastik Bhattacharya


I am interested in understanding the various implications of General Relativity and other such spacetime theories of Gravity. I have worked on the gravitational collapse of massive bodies and formation of black hole or naked singlarity due to this. Currently, I am interested in black hole thermodynamics and generalisations thereof.


Soham Bhattachryya


I work in alternative theories of gravity, especially on f(R) gravity theories; black hole formation and scalar hair in f(R) theories.


Bethan Cropp


My work focuses on understanding theories of gravity through blacks holes in alernative theories of gravity, analogue models of spacetime, and thermodynamics of black holes.


Ophelia Jade Philippine Fabre


My research focuses on early Universe physics, especially on the Cosmic Microwave Background, and includes topology, variation of fundamental constants and magnetic fields generated just before recombination


Santhosh Kumar S


My main area of research interests are Mathematical Physics and Quantum Mechanics. I am currently looking in two areas,

1) non-Hermitian (PT) Quantum Mechanics; how this theory replaces the usual Hermitian property of a physical observable and its interesting applications in Physics.
2) Quantum entanglement of black hole entropy, for understanding the Black hole information.


Kinjalk Lochan


Quantum Gravity, Black holes, Quantum field theory in curved spacetime.


Jose Mathew


My research interests is mainly on early universe, modified gravity models and inflation.


Debottam Nandi


My research interests is mainly on Cosmological Perturbation theory, especially using Hamiltonian formalism (ADM formalism) and also on Gauge invariance in inflationary universe.


Navya Nagananda


I am primarily interested in observational astronomy and exoplanet detection. Currently, I am using data from large scale structures to help break the degeneracy between alternative theories of gravity.


S. Shankaranarayanan


Quantum gravity — an yet unknown theory unifying quantum mechanics and gravity — is considered to be the theory that describes interactions/processes among various particles at Planck energies (∼ 10^16 TeV). Although the bottom-up approaches like String theory and Loop quantum gravity have unearthed some interesting physics, none of them have given a complete theory that works at Planck energies. The top-down approaches like trans-Planckian inflation and modified gravity models are attempts to build a viable, self-consistent phenomenological models to look for broad features with robust experimental signatures. The quest for experimental signatures in the terrestrial experiments like particle colliders is one avenue of investigation, while cosmology — more broadly, gravity — provides another, complementary, direction. Shankaranarayanan's research has centered on the later.




Alumni

Kinjal Banerjee (Current : Faculty, BITS-Goa)



Research Interests:  Loop Quantum Gravity and Cosmology; Hamiltonian Analysis of Gravitational Theories.

From the classical perspective, I am actively interested in obtaining the Hamiltonian formulation of the various theories of gravity which are invariant under Poincare Transformations (PGT) and then to try to rewrite them as SU(2) gauge theories. In quantum gravity , I am interested in a background independent quantization programme known as Loop Quantum Gravity (LQG) and its application to cosmological models. In particular, I am particularly interested in studying inhomogeneous models, via rigorous quantization prescriptions and also by using perturbative and effective theory techniques. I am also interested in several technical issues in LQG like the alternative construction of Hamiltonian constraint operator.


Pramod Dominic (Current : Faculty, JAIN University, Bengaluru)


My general research direction deals with the study of non-supersymmetric attractors in supergravity theories arising from the compactification of type II string theory on Calabi-Yau three folds. The main focus is to study the effect of all sub-leading corrections to the N=2 pre-potential on the non-supersymmetric attractors and to study the stability of these attractors on including these effects. Recently I am working on the holographic entanglement entropy and its connection to the black hole entropy.


Suman Ghosh (Current : Postdoc, TIFR, Mumbai)


Research Interests Black holes, black-rings, brane-world geometry,entanglement entropy, non-symmetric gravity.

Ongoing projects:In higher derivative field theories the so-called entanglement entropy-area law breaks down. It is numerically shown that the entropy, in fact, increasing with decreasing size of the horizon which is a surface that essentially divides a system, in pure quantum state, into two parts which are entangled with each other across the surface. Qualitative understanding of this counter intuitive phenomenon can be achieved through analogical quantum mechanical toy model. Higher dimensional non-symmetric gravity can mimic thick brane-world scenario. The non-symmetric nature of the extra dimensions effectively generates a mass to the electromagnetic field without breaking the gauge-invariance of the electromagnetic field. Thus this model has potential to solve the long standing problem with generation of primordial magnetic fields.


Jerome Mathew Kovoor


My main areas of interest are cosmology and high energy astrophysics. Currently I am working on “Detection of primordial magnetic fields in CMB polarization data taken from PLANCK satellite”. I am also interested in theory of cosmological perturbations and formation of large scale structures.


Abhishek Majhi (Current: Postdoc, Universidad Nacional Autonoma de Mexico)


During my Ph.D. years I have mainly dealt with issues regarding thermodynamics of black holes in loop quantum gravity framework. Recently, I have been looking into some other issues which I look forward to explore in the near future e.g. black hole radiation and its back reaction in LQG framework, field theory on a dynamical horizon, entanglement entropy in LQG, etc.


Krishnanand Mallayya  (Current: Ph.D, Pennsylvania State University, USA)


My work was in understanding the divergence of entanglement entropy in the ground state of scalar field, and the role of zero modes in the divergence, I have also been studying the effect of adding higher order derivatives to the ground state and its entanglement.


Sushruth Muralidharan (Current: Ph.D. University of Buffalo, NY)


Eigenstate thermalisation Hypothesis in quantum many body systems. Currently I am looking at eigenstate thermalization in a quantum harmonic oscillator chain with long range interactions and second order interactions.


Soham Pal  (Current: Ph.D, Iowa State University,Iowa)


I have earlier worked on quantum effects in classical black hole background. Currently I am interested in studying phase transitions observed in condensed matter systems. These phase transitions occur due to the presence of topological defects, such as vortices in a superfluid, in the system. It is generally believed that such topological defects were formed during the very early stages of the Universe and were the generators of the phase transitions that shaped the early universe. Though it is not possible to reproduce these cosmological defects in the laboratory, we can still gain a lot of information about the early Universe by studying analogous topological defects and the consequent phase transitions in condensed matter systems.


Jose Luis Lopez Picon (Postdoc, Guanajuato U, Mexico)

Research interest: General relativity, generalized theories of gravity and black hole physics.


Karthik R (Current: Ph.D, IUCAA, Pune)


I have worked on the quantization of quasinormal modes and its applications to black hole thermodynamics. I am interested to explore how a zero-point length (of the order of Planck length) can possibly capture the leading order effects of quantum gravity. My current interest is towards the fluid dynamics - gravity correspondence.


Jozef Skakala (Current: Scientist, Plymouth Marine Laboratory, Plymouth)


Spacetime thermodynamics, concept of horizon entropy, possible link between quasi-normal modes and the thermodynamics of horizons, perturbations in (and of) classical spacetimes


Rakesh Tibrewala (Current: Assistant Professor, LMIT, Jaipur)


Research Interests:  My work has mostly focused on studying the implications of loop quantum gravity on gravitational collapse and on black hole spacetimes. I am also interested in aspects of inflationary cosmology and its implications for the CMB. More recently I have also been looking at black hole entropy and its relation to entanglement entropy.


Sanil Unnikrishnan (Current: Assist Professor, St. Stephen College, Delhi)


Research Interest : Cosmological perturbation Theory, Dark Energy, Inflation and early universe,Modified theories of Gravity.

My research work involves application of the cosmological perturbation theory in numerous problems in cosmology such as structure formation, distinguishing models of dark energy (and modified gravity models) from the study of growth of large scale structures in the Universe. In addition, I am also investigating the viability of non-canonical scalar fields as a model of inflation and dark energy.