Null Test of the Gravitational Inverse Square Law

Experimental status of gravitational-strength forces in the sub-centimeter regime

“…Well before the interest in gravitational measurements brought on by suggestions of a "fifth force," the report of a possible deviation in a measurement by Long [5] motivated several similar experimental programs (see, for example, Refs. [6][7][8]) which have apparently ruled out any evidence for the anomaly [9].…”

Gauss’s law test of gravity at short range

“…The result is a = (0.9 ± 4.6) x 10 " 4 at A, = 1.5 m, where 0= -(GM/r)(\ +ae ~r /x ) and the error corresponds to a 2<T level. This represents an improvement of 2 orders of magnitude over our previous result [2] and more than an order of magnitude over the best existing limit [3].…”

Tests of the Gravitational Inverse Square Law at Short Ranges

“…Other lines are 1σ limits, except the Eöt-Wash line which is a 2σ limit on |α|. References are as follows: Irvine I and II: (Spero et al 1980;Hoskins et al 1985), Eöt-Wash: (Kapner et al 2007), Cambridge: (Chen et al 1984), Maryland I and II: (Chan et al 1982;Moody and Paik 1993), Panov: (Panov and Frontov 1979), Ogawa: (Ogawa et al 1982. A corresponding plot for positive α is presented in Fig.…”