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Do planets grow pebble-by-pebble or collapse in a single sweep? Core accretion and gravitational instability predict very different fingerprints in young disks, yet catching those signatures demands resolution from sub-au to kilometric scales. I will present a continuous, multi-scale view that starts with the brightest Ophiuchus disks: ALMA Band-8 data show they are surprisingly compact with a median ≈14 au, and already structured, pointing to early pressure traps that let core accretion get started before dust can drift away. At the opposite extreme, ERIS imaging of the eruptive FU or V960 Mon exposes a dust-enshrouded companion >1500 au out, nested in a fragmenting spiral arm, direct evidence that gravitational instability can still ignite in massive, cold outer disks. Bridging these regimes, VLTI/GRAVITY and CHARA observations resolve inner-rim geometries and gas tracers inside 1 au, where accretion flows and nascent hot Jupiters reshape disk dynamics. Taken together, the data suggest that both formation routes operate, each favored by distinct disk conditions.
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