Ever wondered how the universe came into existence? The component with which matter and antimatter were formed? Dr Basabendu Barman, Assistant Professor at the Department of Physics, in his research paper, titled- Leptogenesis, Primordial Gravitational Waves, and PBH-induced Reheating delves into the truth of the formation of matter. Read this exciting paper featured in Physics Review D to learn more!
Abstract:
We explore the possibility of producing the observed matter-antimatter asymmetry of the Universe uniquely from the evaporation of primordial black holes (PBH) that are formed in an inflaton-dominated background. We show it is possible to obtain the desired baryon asymmetry via vanilla leptogenesis from evaporating PBHs of initial mass around 10g. We find that the allowed parameter space is heavily dependent on the shape of the inflaton potential during reheating, the energy density of PBHs, and the nature of the coupling between the inflaton and the Standard Model (SM). To complete the minimal gravitational framework, we also include in our analysis the gravitational leptogenesis set-up through inflaton scattering via exchange of graviton, which opens up an even larger window for PBH mass, depending on the background equation of state. We finally illustrate that such gravitational leptogenesis scenarios can be tested with upcoming gravitational wave (GW) detectors, courtesy of the blue-tilted primordial GW with inflationary origin, thus paving a way to probe a PBH-induced reheating together with leptogenesis.
Practical Implementations & Social Impact:
The first implication lies in the realm of intellect. The question, “Why is the Universe the way it is?” is profoundly significant and has likely intrigued humanity since the dawn of civilization. While technological advancements have allowed us to unravel many of the Universe’s mysteries, we have also come to realize that “what we know is a drop, and what we don’t know is an ocean.” As theoretical particle physicists, our role is to explore this vast ocean of the unknown—a pursuit for which we are rigorously trained. This underscores the vital importance of studying fundamental science. From a practical perspective, our study highlights the crucial role that experiments play in uncovering new knowledge. The synergy between theory and experiment, as we propose, could soon lead to groundbreaking discoveries—or, alternatively, our theory could be disproven if no evidence is found. Either way, it is essential to have advanced experimental facilities and more sensitive detectors to carry out these investigations. This, in turn, calls for increased funding and support for research in the field of high-energy physics.
Collaborations:
India (IIT: Guwahati, Kanpur, Hyderabad; IACS, Kolkata; IOP, Bhubaneswar).
Colombia (Universidad de Antioquia, Universidad de Santiago de Chile).
Abu Dhabi (New York University, Abu Dhabi).
Brazil (IIP, Natal).
Germany (Mainz Institute for Theoretical Physics [MITP], Mainz).
Poland (University of Warsaw).
Spain (Universidad Complutense,Madrid; IFIC, Valencia).
China (T D Lee Institute).
Korea (IBS, Daejeon; KIAS, Seoul; Kyungpook National University, Daegu).
Japan (Hokkaido Univeristy).
France (IJC Lab, Paris).
Sweden (KTH, Stockholm)
US (Washington University, St. Louis; University of Minnesota; Indiana University; University of Pittsburgh, University of Kentucky).
Future Plans:
A closer look into early universe dynamics by performing more involved simulations.Connection between particle physics models and early Universe cosmology.Complementary searches from different experiments in unravelling new physics beyond the Standard Model.
Link: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.043528
