Type Ia Supernovae and their Explosive Nucleosynthesis: Constraints on Progenitors

What the progenitors of Type Ia supernovae (SNe Ia) are, whether they are near-Chandrasekhar mass or sub-Chandrasekhar mass white dwarfs, has been the matter of debate for decades. Various observational hints are supporting both models as the main progenitors. In this paper, we review the explosion physics and the chemical abundance patterns of SNe Ia from these two classes of progenitors. We will discuss how the observational data of SNe Ia, their remnants, the Milky Way Galaxy, and galactic clusters can help us to determine the essential features where numerical models of SNe Ia need to match.