Recent conjectures suggest the universe may have large extra dimensions, through which gravity propagates. This implies gross departures from Newton's law of gravity at small length scales. Here I consider some implications for particle dynamics on scales comparable to the compactification radius, Rc ≲ 1 mm. During planet formation, coalescence of micron sized dust grains to planetesimals is a rate critical step. Blum et al. (2000) found dust grain aggregates form low fractal dimension structures in microgravity, consistent with high angular momentum coalescence. I consider the effects of non-Newtonian gravity on dust aggregation on scales less than Rc and show they naturally coalesce into low-dimensional structures with high specific angular momentum. We infer Rc ≈ 80 microns.
All Science Journal Classification (ASJC) codes
- Mathematical Physics
- Astronomy and Astrophysics
- Space and Planetary Science