Accretion through circumstellar disks plays an important role in star formation and in
establishing the properties of the regions in which planets form and migrate. The …

Protoplanetary disks are quasi-steady structures whose evolution and dispersal determine
the environment for planet formation. I review the theory of protoplanetary disk evolution and …

Transient heating events that formed calcium-aluminum–rich inclusions (CAIs) and
chondrules are fundamental processes in the evolution of the solar protoplanetary disk, but …

Flattened, rotating disks of cool dust and gas extending for tens to hundreds of astronomical
units are found around almost all low-mass stars shortly after their birth. These disks …

The filamentary nature of accretion streams found around embedded sources suggests that
protostellar disks experience heterogenous infall from the star-forming environment …

We present the latest development of the disk gravitational instability and fragmentation
model, originally introduced by us to explain episodic accretion bursts in the early stages of …

The detection of quasars at z> 6 unveils the presence of supermassive black holes of a few
billion solar masses. The rapid formation process of these extreme objects remains a …

The transport of angular momentum by magnetic fields is a crucial physical process in the
formation and evolution of stars and disks. Because the ionization degree in star-forming …

Planets appear to form in environments shaped by the gas flowing through protostellar disks
to the central young stars. The flows in turn are governed by orbital angular momentum …

The prevalence of substructures in∼ 1–10 Myr old protoplanetary disks, which are often
linked to planet formation, has raised the question of how early such features form and, as a …