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Experimental hints of Gravity in Large Extra Dimensions?

Steinn Sigurdsson
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Abstract

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, $R_c \ltorder 1$ 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 $R_c$ and show they naturally coalesce into low dimensional structures with high specific angular momentum. We infer $R_c \approx 80$ microns.

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Steinn Sigurdsson. 2001-07-09. Experimental hints of Gravity in Large Extra Dimensions?. https://doi.org/10.1142/s0218271801001566

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