there are infinite worlds both like and unlike

``there are infinite worlds both like and unlike this world of ours …’’ Epicurus 59/59

7/69

Precision COSMOGONY • Ubiquity of planets: case study vs Science • Diversity of systems: realm of possibilities Integral of details • Population census missing info & big picture • Solar system connection Anthropic principle 5/69 Survival of fittest

6/59

Conventional core accretion scenario 7/59

Major Challenges: • Retention of grains: m-size barrier (Whipple) • Fragmentation: km-size barrier (Benz) • Planetesimal-growth barrier: Isolation mass barrier (Wetherill) • Gas accretion barrier: critical-mass cores (Cameron) • Retention of cores: type I migration (Goldreich & Tremaine, Ward) • Retention of gas giants: type II migration (Lin & Papaloizou) • Multiple gas giants: rapid depletion of disk gas • Competing physics on multiple length & time scales 8/59

Step I: Meter-barrier ngas=(GM/a 3)1/2(1 – h) H= -a 3/2 GMr (d. P/dr) Hydrodynamic drag on dusts 9/59

Trapping locations: transition fronts and wall of magnetospheric cavity d. M/dt=rsv. AFg Fg= 1 + (ve 2/v 2) 10/59

Major Challenges: • Retention of grains: m-size barrier (Whipple) • Fragmentation: km-size barrier (Benz) • Planetesimal-growth barrier: Isolation mass barrier (Wetherill) • Gas accretion barrier: critical-mass cores (Cameron) • Retention of cores: type I migration (Goldreich & Tremaine, Ward) • Retention of gas giants: type II migration (Lin & Papaloizou) • Multiple gas giants: rapid depletion of disk gas • Competing physics on multiple length & time scales 11/59

Planetesimal growth in a trap 12/59

Stalling of planets inside & at the magnetospheric truncation radius Mass Accretion Rate et al. 1998 Stellar Dipole Moment Hartmann Magnetosphere radius 13/59 Herczeg