http://arxiv.org/abs/2301.07456
We study the evolution of abelian electromagnetic as well as non-abelian gauge fields, in the presence of space-time oscillations. In the non-abelian case, we consider linear approximation, to analyse the time evolution of the field modes. In both abelian and non-abelian, the mode equations, show the presence of the same parametric resonant spatial modes. The large growth of resonant modes induces large fluctuations in physical observables including those that break the $CP-$symmetry. We also evolve small random fluctuations of fields, using numerical simulations in $2+1$ dimensions. These simulations help study non-linear effects $vs$ the gauge coupling, in the non-abelian case. Our results show that there is an increase in energy density with the coupling, at late times. These results suggest that gravitational waves may excite non-abelian gauge fields more efficiently than electromagnetic fields. Also, gravitational waves in the early Universe and from the merger of neutron stars, black holes etc. may enhance $CP-$violation and generate an imbalance in chiral charge distributions, magnetic fields etc.
S. Dave, S. Digal and V. Mamale
Thu, 19 Jan 23
78/100
Comments: 19 pages, 16 figures