content_image/340267.jpg content_image/340272.jpg
can mimic assisted inflation [286] $^{79}$. 

## Beyond MSSM : 

A gauge invariant inflationary model has been proposed sometime ago in in Ref. [746]. The idea is that ( SU (3)) 3 gauge group is spontaneously broken down to SU (3)$_{c}$ × SU (2)$_{L}$ × SU (2)$_{R}$ × U $^{(1)$_{B}$}$− $_{L}$. The quartic contribution to the superpotential is given by a D -flat direction of ( SU (3)) $^{3}$, Φ, which is invariant under 27, 

<img src='content_image/340267.jpg'>

where λ is a small number determined by matching the amplitude of the CMB observations, and Φ is the monomial representing, N, ¯ N or ν $^{c}$, ¯ ν $^{c}$. The potential along such a D -flat direction is given by [746]: 

<img src='content_image/340272.jpg'>

where M$_{S}$ ∼ 10 3 GeV, denotes the soft SUSY breaking scale. It was argued that the negative mass squared term would appear due to running in presence of strong dynamics [746]. Inflation happens near φ ∼ 0, and ends with a VEV, φ ∼ M ∼ λ − 1 / 2 √$_{M}$$_{P}$$_{M}$$_{S}$ GeV. In order to match the CMB temperature anisotropy, Δ T/T ≈ 0 . 023 λN 2 $_{Q}$, where N$_{Q}$ = (2 π/ 3)( φ/M$_{P}$ ) 2 is the number of e-foldings before the end of inflation. We require M ∼ 10 15 GeV and λ ∼ 10 − 7 [746]. The spectral index for the scalar perturbations tend to be small n ≃ 0 . 92 − 0 . 88, while the ratio of the tensor to the scalar ratio is given by; r ≈ 0 . 4 − 0 . 7. 

