Torsion-Balance Limits on a Yukawa Fifth Force Between Ten Micrometres and a Centimetre, Recomputed in the Frame

A fifth force of Yukawa form - gravitational strength scaled by a factor alpha_Y and cut off beyond a range lambda - is fenced by torsion-balance experiments across the micrometre-to-centimetre window. Using the published exclusion curve (Kapner et al. 2007; Adelberger et al. 2009), a force of gravitational strength is excluded for ranges above about 3.0e-05 metres; at a range of 100 micrometres the permitted strength is already a factor 3.33e+02 below gravity, and at one millimetre a factor 3.33e+04 below. Any torsion-mediated Yukawa interaction proposed within the frame must sit beneath this curve, which in practice confines unsuppressed frame forces to ranges below tens of micrometres, where other experiments take over. The tabulated limits are approximate read-offs from published curves, used as such. Computed, not measured.