Abstract Details
| Name: Kandaswamy Subramanian Affiliation: Inter-University Centre for Astronomy and Astrophysics Conference ID: ASI2016_761 Title : Origin of Cosmological magnetic fields: Primordial AND dynamos? Authors and Co-Authors : Kandaswamy Subramanian (IUCAA) Abstract Type : Invited Abstract Category : General Relativity and Cosmology Abstract : Inflation provides a natural setting for the generation of coherent primordial magnetic fields. However, one needs to overcome several challenges to do with the predicted strength of the field and the strong coupling problem. We discuss possible resolutions. Even if the origin were primordial, dynamos are essential for maintaining the field. We show that this can occur easily if the field were strong and helical. For non-helical or weak fields conventional dynamos are required. We review recent work which shows that fluctuation dynamos could indeed provide the degree of coherence needed for cluster fields, and that mean-field dynamos could indeed generate large-scale fields on saturation, even in the presence of strongly growing fluctuations! |