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Abstract

The rich diversity of exoplanets discovered in various physical environments clearly shows that planet formation is an efficient process with multiple outcomes. To un- derstand the emergence of newborn planets, one can rewind the clock of planetary systems by investigating the formation and evolution of their natal environment, the so-called protoplanetary disks. In the core accretion scenario, rocky planets such as the Earth are thought to be formed from cosmic dust particles that grow into pebbles and planetesimals, the building blocks of planets, later assembling to- gether. An intricate puzzle in this theory is how exactly these building blocks are formed and kept long enough in the natal protoplanetary disk. Protoplanetary disks are weakly magnetized accretion disks that are subject to the magnetorotational instability (MRI). It is to date one of the main candidates for explaining their turbulence and angular momentum transport. The nonideal magnetohydrodynamic effects prevent the MRI from operating everywhere in the protoplanetary disk, leading to MRI active regions with high turbulence and non- MRI regions with low turbulence. It has been hypothesized that these variations in the disk turbulence can lead to pressure maxima where dust particles can be trapped. In these so-called dust traps, dust particles can grow efficiently into peb- bles and potentially planetesimals. Yet, it is still an open question how this MRI- powered mechanism shapes the secular evolution of protoplanetary disks, and how it is involved in the first steps of planet formation. It is because the interplay of gas evolution, dust evolution (dynamics and grain growth processes combined) and MRI-driven turbulence over millions of years has never been investigated. The central goal of this thesis is to bridge the gap in the core accretion scenario of planet formation by building the very first unified disk evolution framework that captures self-consistently this interplay. The unique approach adopted in this thesis leads to an exciting new pathway for the generation of spontaneous dust traps everywhere in the protoplanetary disk, which can be potential birth-sites for planets by forming and keeping their necessary building blocks.