Holes That Push

Every mass on the field pulls. Nothing can bend a stream outward.

Repulsion is a negative mass

GravityMass pulls with m·d / (|d|² + ε²)^1.5, where d points at the mass. Make m negative and the same sum points away. A rock flying straight at it gets only as close as its energy allows, and stops where that runs out: ½v² = S / r, so r = 2S / v². At the chute's 11 units a second, a white hole of strength 300 turns a rock back 4.96 units out.