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that N → 2 annihilations ( N > 2) are forbidden: annihilation of particle (or anti-particle) quanta cannot happen without violating the net particle number density. Therefore the total number density of quanta will not decrease, and the average energy will not increase $^{95}$. 

Any possible non-perturbative particle production in the rotating condensate case will result in a plasma which is at least as dense as the initial condensate. All that can happen is a redistribution of the energy density among the fields on the D -flat subspace. These fields have masses comparable to the flat direction mass m$_{0}$ , as they all arise from SUSY breaking. Since the average energy is E$_{ave}$ ≤ m$_{0}$ , the resulting plasma essentially consists of non-relativistic quanta. Its energy density ρ = ˜ nE$_{ave}$ is therefore redshifted ∝ a − $^{3}$. The decay of a rotating condensate happens quite late [410] 

where m . d . corresponds to matter domination and r . d . corresponds to radiation domination, and y is the Yukawa coupling of the flat direction to MSSM matter. The decay happens essentially perturbatively for yϕ$_{0}$ > m$_{0}$ , as envisaged by [324–326] 

## 4. SUSY thermalization 

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Flat directions VEV can dramatically affect thermal history of the universe. The reason is that the MSSM flat direction VEV spontaneously breaks the SM gauge group. The gauge fields of the broken symmetries then acquire a SUSY conserving mass, m$_{g}$ ∼ g | ϕ | , from their coupling to the flat direction, where g is a gauge coupling constant. In which case a flat direction can crucially alter thermal history of the universe by suppressing thermalization rate of the reheat plasma. Note that, m$_{g}$ , provides a physical infrared cut-off for scattering diagrams with gauge boson exchange in the t − channel shown in Fig. (A). The thermalization rate will then be given by (up to a Logarithmic “bremsstrahlung” factor): 

where we have used m 2 g ≃ g $^{2}$| ϕ | 2 where α ∼ g $^{2}$/ 4 π . After the flat direction starts its oscillations at H ≃ m$_{0}$ ∼ O (100) GeV, the Hubble expansion redshifts, | ϕ | 2 ∝ a − $^{3}$, where a 

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