Executive Summary : | The understanding of the generation and evolution of magnetic fields in the early universe is a significant challenge in cosmology. Although magnetic fields of different magnitudes and length scales exist, their origin is not well established. Several methods have been used to generate primordial magnetic fields, but most are small and inadequate to explain current galactic and inter galactic magnetic fields. The Biermann mechanism and magnetohydrodynamic evolution have been used to generate larger fields with longer lengthscales. Magnetic fields generated in the early universe may leave their imprints on observables like cosmic microwave background radiation (CMBR). The group has published two methods of generating primordial magnetic fields using topological defects, showing that collapsing Z(3) domain walls and moving cosmic strings can generate these fields. They are currently using the magnetohydrodynamic code OpenMHD to model the evolution of magnetic fields in the early universe, aiming to study the evolution of magnetic fields generated from topological defects and relate them to possible observational signatures. Observational signatures of primordial magnetic fields are expected in CMBR and major collaborations like SKA, where the UV luminosity function of high redshift galaxies can constrain the magnitude of the magnetic field at the end of the reionization process. The group plans to match large-scale simulation results with data from SKA and compare simulation results to experiments to confirm the presence of topological defects in the plasma and provide details of the evolution of magnetic fields in the early universe. |