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I am happy to be back in blogosphere after a gap of around one and a half months. There were too many things I was involved in related to the administrative branch of my home institute. Slow and inefficient Indian bureaucracy takes too much time to get things done, can't help it. Anyway, I am feeling quite blank regarding what to post. The easiest thing to post is about my latest paper which appeared in arxiv last week. The title of this post is the arxiv pre-print number of my article.

The paper titled as " Spontaneous Parity Breaking and Supersymmetry Breaking in Metastable Vacua with Consistent Cosmology" is all about study of some cosmological issues in a model where Left-Right symmetry can be broken spontaneously as well as Supersymmetry can be broken in a metastable vacua without any reference to hidden sectors (like in usual Supersymmetry breaking models) . Such a model was constructed recently by a Japanese group, we study it in details and point out some cosmological issues which needs to be addressed. The issue is related to the formation of domain walls (extended two dimensional topological objects) which are formed after the phase transition accompanying the discrete left right symmetry breaking. These domain walls have very high energy density compared to usual matter or radiation and if they start dominating the Universe, the standard cosmology will be in trouble in view of recent experimental data from WMAP (Wilkinson Mass Anisotropy Probe). We discussed some techniques to get rid of such unwanted walls in earlier works also and the basic idea is to incorporate gravitational effects which break the discrete symmetry explicitly leading to a pressure difference across the walls. Thus the true vacuum will expand and occupy the entire observable Universe. The model we are studying in this present paper is however different from earlier models in the sense that here both left right symmetry breaking and supersymmetry breaking mechanisms are specifically mentioned, that too without talking about hidden sectors. Such theories are based on Seiberg duality which relates a UV free supersymmetric gauge theory to an IR free magnetic theory thereby making computations easier in both the regimes. The magnetic theory , if assumed to describe the low energy world, also breaks Supersymmetry spontaneously. Supersymmetry preserving vacua also appear dynamically in the magnetic theory leading to metastable vacua. The work I have done, studied the constraints coming from such long lifetime of metastable vacua as well as domain wall disappearance in the left right symmetric model. The life time constraint gives a lower bound on the left right symmetry breaking scale whereas the domain wall disappearance puts an upper bound on that scale. Fortunately these bounds don't conflict each other and more excitingly the lower bound coming from long life time of metastable vacua requirement lies pretty close to the TeV scale. Anyway much more work needs to be done in these models and our work just tells a tiny part of it concerning mainly the domain wall disappearance!