Gravity Waves from the Nonperturbative Decay of Condensates along Supersymmetric Flat Directions

Nonperturbative effects may lead to an explosive decay of flat direction condensates in supersymmetric theories. We confirm the efficiency of this process with lattice simulations: After only one to five rotations of the condensates in their complex plane, most of their energy is converted into inhomogeneous fluctuations. This generates a gravitational wave background, which depends on the inflaton sector and falls in the hertz-kilohertz frequency range today. These gravity waves can be observable by upcoming experiments such as Advanced LIGO and depend crucially on (i) the initial vacuum expectation value of flat directions when they start to oscillate, (ii) their soft supersymmetry-breaking mass, and (iii) the reheat temperature of the Universe. This signal could open a new observational window on inflation and low-energy supersymmetry.