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the ΛCDM model. This work has been done in collaboration with Wompherdeiki Khyllep Thermodynamics of scalar field models with kinetic corrections In this work, we compare the thermodynamical vi- ability of two types of non-canonical scalar field models, with kinetic corrections: the square kinetic and square root kinetic corrections. In modern cosmology, the generalized second law of thermo- dynamics (GSLT) plays an important role in de- ciding thermodynamical compliance of a model as one cannot consider a model to be viable if it fails to respect GSLT. Hence, for comparing thermody- namical viability, we examine the validity of GSLT for these two models. For this purpose, by em- ploying the unified first law (UFL), we calculate the total entropy of these two models in appar- ent and event horizons. The validity of GSLT is then examined from the autonomous systems, as the original expressions of total entropy are very complicated. Although, at the background level, both models give interesting cosmological dynam- ics, however, thermodynamically we found that the square kinetic correction is more realistic as com- pared to the square root kinetic correction. More precisely, the GSLT holds for the square kinetic cor- rection throughout the evolutionary history except only during the radiation epoch, where the scalar field may not represent a true description of the matter content. On the other hand, the square root kinetic model fails to satisfy the GSLT in major cosmological eras. This work has been done in col- laboration with Binod Chetry, and Wompherdeiki Khyllep. Sunandan Gangopadhyay Cosmology of Bianchi type-I metric using renor- malization group approach for quantum gravity We study the anisotropic Bianchi type-I cosmolog- ical model at late times, taking into account quan- tum gravitational corrections in the formalism of the exact renormalization group flow of the effec- tive average action for gravity. The cosmological evolution equations are derived by including the scale dependence of Newton’s constant G and cos- mological constant Λ. We have considered the solu- tions of the flow equations for G at next to leading order in the infrared cutoff scale. Using these scale dependent G in Einstein equations for the Bianchi-I model, we obtain the scale factors in different direc- tions. It is shown that the scale factors eventually evolve into FLRW universe for known matter like radiation. However, for dust and stiff matter, we find that the universe need not evolve to the FLRW cosmology in general, but can also show Kasner type behaviour. This work has been done in col- laboration with Rituparna Mandal, and Amitabha Lahiri. Holographic entanglement entropy and generalized entanglement temperature In this work, we study the flow of holographic en- tanglement entropy in dimensions d ≥ 3 in the gauge/gravity duality setup. We observe that a generalized entanglement temperature T g can be defined, which gives the Hawking temperature T H in the infrared region and leads to a generalized thermodynamics like law, E = d − 1 d T g S REE , which becomes an exact relation in the entire re- gion of the subsystem size l , including both the infrared ( l → ∞ ) as well as the ultraviolet ( l → 0) regions. Furthermore, in the IR limit, T g produces the Hawking temperature T H along with some cor- rection terms, which bears the signature of short distance correlations along the entangling surface. Moreover, for d ≥ 3, the IR limit of the renormal- ized holographic entanglement entropy gives the thermal entropy of the black hole as the leading term; however it does not have a logarithmic cor- rection to the leading term unlike the Ba¨nados, Teitelboim, Zanelli (BTZ) black hole ( d = 2). The generalized entanglement temperature T g also firmly captures the quantum mechanical to thermal crossover in the dual field theory at a critical value l c of the subsystem size in the boundary, which we graphically represent for AdS 3+1 and AdS 4+1 black holes. We observe that this critical value l c where the crossover takes place decreases with increase in the dimension of the spacetime. This work has been done in collaboration with Ashis Saha and Jyoti Prasad Saha. Suman Ghosh Particle creation by a massless spin- 1 2 field in a warped cosmological braneworld scenario Energy momentum tensor of a quantised massless bulk spin- 1 2 field in five dimensional warped cosmo- logical spacetimes is studied. The four dimensional part of our model represents a warped cosmological