Current Research
I work as a graduate student with Dr. Katherine Mack (@astrokatie) at the Department of Physics at NC State University in Raleigh, North Carolina. I work in cosmology, which is the study of the large-scale universe, its origins, its content, and its fate.
My current research is in collaboration with Dr. Adrienne Erickcek’s group at UNC, Chapel Hill. I am currently studying the formation of microhalos in the very early universe. These might arise due to Early Matter Dominated Eras (EMDEs), which arise in theories with “hidden” dark sectors. I do theory and N-body simulations of structure formation during and after the EMDE, with the aim of studying microhalo statistics to accurately model the dark matter annihilation signal.
Here is a picture from a small simulation I ran. Dark matter, aided by gravity, organises itself into this cosmic web of filaments and clusters. Ordinary matter falls into these clusters to form galaxies:
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Here is some of my previous work:
An Effective Field Theory of Large Scale Structure
As work for my Master’s Thesis, I reviewed an exciting new effective field theory formalism of large-scale structure in the universe. This approach includes nonlinear (second-order) perturbations as source terms in the density perturbation equations for dark matter, and seeks to build solutions through Green’s Functions of the first order density and velocity perturbation equations.
I worked under Dr. Debashis Ghoshal at the School of Physical Sciences, Jawaharlal Nehru University, Delhi. Here’s the report.
The Non-Universality of the Mass Function
A report from the work I did at the Indian Institute of Science Education and Research, Mohali, under Dr. Jasjeet Singh Bagla, in the summer of 2017.
The Sheth-Tormen halo mass function is believed to have a pair of “universal” parameters: they do not depend on either the background cosmology, or the statistics of the underlying dark matter distribution. Using a suite of N-body simulations, I am trying to relate the “tilt” of the power spectrum of dark matter with these parameters.
Physics GRE
For those studying for the Physics GRE, here is my collection of resources, including all five released tests and their solutions, extra practice problems, sets of notes and general tips.
A Gentle Introduction To Classical Fields
Here is a short term paper I wrote, explaining classical field theory.
On The Uses of Proper Time in Special Relativity
The proper time is useful as a parameter for spacetime coordinates, as well as an effective Lagrangian in special relativity.
Here is a small write-up detailing the same.
On The Impact of Massive Neutrinos on Large-Scale Structure
I did my bachelor’s thesis at NCRA-TIFR in Pune, working on N-body simulations using GADGET-2. I modified the initial conditions code N-GenIC to include provisions for massive neutrinos using the fit functions provided by Hu and Eisenstein. I then studied the suppression of the matter power spectrum at small scales due to neutrino mass.
Here is a link to my thesis.
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