  Left-right symmetric gauge theory presents a minimal paradigm to accommodate
massive neutrinos with all known conserved symmetries duly gauged. The work
presented here is based on the argument that the see-saw mechanism does not
force the new right handed symmetry scale to be very high, and as such some of
the species from the spectrum of the new gauge and Higgs bosons can have masses
within a few orders of magnitude of the TeV scale. The scale of the left-right
parity breaking in turn can be sequestered from the Planck scale by
supersymmetry. We have studied several formulations of such Just Beyond
Standard Model (JBSM) theories for their consistency with cosmology.
Specifically the need to eliminate phenomenologically undesirable domain walls
gives many useful clues. The possibility that the exact left-right symmetry
breaks in conjunction with supersymmetry has been explored in the context of
gauge mediation, placing restrictions on the available parameter space. Finally
we have also studied a left-right symmetric model in the context of metastable
supersymmetric vacua and obtained constraints on the mass scale of Right handed
symmetry. In all the cases studied, The mass scale of right handed neutrino
$M_R$ remains bounded from above, and in some of the cases the scale $10^9$ GeV
favourable for supersymmetric thermal leptogenesis is disallowed. On the other
hand PeV scale remains a viable option, and the results warrant a more detailed
study of such models for their observability in collider and astroparticle
experiments.
