New macroscopic forces?

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

“…IV, but could be a possible goal for the future [32]. Moody and Wilczek [33] have argued that centimeter-scale experiments with polarized bodies would be more promising, and several attempts in this direction have been made [34][35][36][37].…”

Searches for invisible axions

“…Axions mediate a monopoledipole interaction potential between spin and matter [67] given by where gs and gp are coupling constants at the scalar (s) and polarized (p) vertices, a and r'the spin and separation vectors, m, the mass at the polarized vertex, and X the range of the force (N l/ma) For axions with mass within the window l-1000 PeV, the corresponding X is 0 2-200 mm The scalar coupling gs is proportional to the strong inter&ion CP violating parameter e, and the product of couplings is Recall that null searches for a neutron edm conservatively imply 8 < IO-', and the axion resulted from a scheme to drive 8 to zero However, in the Standard Model plus axions, 6 does not identically vanish There remains a small contribution from known sources of weak interaction CP violation, at the level of perhaps 8 N lo-i4 [67] should weak interaction CP violation arise from the Kobayashi-Maskawa model Axions would be signaled by a weak Yukawatype gravitational force at short but macroscopic distances, with strength proportional to the CP violating parameter 8.…”

GAUGE: the GrAnd Unification and Gravity Explorer

“…Axions, and axion-like particles, couple to both the scalar (or spin independent) and pseudoscalar (spin dependant) vertex [10]. This causes three distinct interactions: scalar-scalar (mass-mass), scalar-pseudoscalar (massspin) and pseudoscalar-pseudoscalar (spin-spin).…”

“…An experimental increase in the limit will provide guidance on effective quantum gravity energy scales, especially in relation to (non)renormalization properties of quantum gravity. In order to test (10) and determine the model dependent form factor A in relation to (11), GAUGE atom interferometry experiments will be carried out by varying the particle measurement parameters including flight time t, particle mass (using two species: Cs and Rb) as well as particle numbers N. Environmental parameters including pressure and temperature will be monitored to determine the possible level of gravitational decoherence effects. This section has discussed a range of experiments targeting a number of different scientific goals.…”