Levon Pogosian

Research

My research uses cosmological observations to test fundamental physics. I work on a range of topics in theoretical cosmology, including the cosmic microwave background, large scale structure, dark energy, cosmological tests of gravity, primordial magnetic fields, and topological defects such as cosmic strings, domain walls, and magnetic monopoles.

More recently, this work has also included the Hubble tension and other cosmological tensions, along with the development of methods and models that connect new observations to possible physics beyond the standard cosmological model.

Cosmological Tests of Gravity and Dark Energy

A major theme of my work is using cosmological data to test gravity on the largest observable scales and to constrain alternatives to the standard dark energy picture. This includes phenomenological frameworks for modified gravity, observational signatures in structure growth and lensing, and tools for connecting theory to current and future surveys.

Primordial Magnetic Fields and the Early Universe

I work on the generation, evolution, and observational consequences of cosmic magnetic fields, especially primordial magnetic fields and their imprints on the cosmic microwave background. These relics of the early universe can offer a window onto high-energy physics and may also be relevant to current cosmological tensions.

Probing fundamental physics with CMB and LSS

The Cosmic Microwave Background (CMB) radiation is a snapshot of our Universe at the age of 400,000 years and bears signatures of events that happened before and after. I use the CMB measurements along with the data from large scale structure surveys to gain insight into the fundamental physics, with special interest in primordial magnetic fields, neutrinos, dark matter and dark energy.

Topological Defects and Relics of the Early Universe

Another long-standing research direction is the physics of topological defects and related relics of the early universe, including cosmic strings, domain walls, and magnetic monopoles. These objects provide concrete examples of how particle physics beyond the Standard Model may leave observable cosmological signatures.