E-print Articleshttps://repository.iitgn.ac.in/handle/123456789/6152020-05-25T09:38:07Z2020-05-25T09:38:07ZThermal transport in a weakly magnetized hot QCD mediumKurian, Manuhttps://repository.iitgn.ac.in/handle/123456789/54152020-05-21T10:45:25Z2020-05-01T00:00:00ZThermal transport in a weakly magnetized hot QCD medium
Kurian, Manu
The thermal transport coefficients in a weakly magnetized quark-gluon plasma have been investigated within the ambit of a quasiparticle model to encode the effects of the realistic equation of state. The presence of a weak magnetic field leads to the Hall-type conductivity associated with thermal transport in the medium. An effective covariant kinetic theory has been employed to quantify the thermal dissipation while incorporating the mean field contributions in the medium. The interplay of thermal transport and electric charge transport in the weakly magnetized medium has been explored in terms of the Wiedemann-Franz law. Strong violation of the Wiedemann-Franz law has been observed in temperature regimes near to the transition temperature. The behaviour of thermal conductivity in the strong magnetic field limit has also been studied. It is observed that both the magnetic field and equation of state have a significant impact on the thermal dissipation in the medium.
2020-05-01T00:00:00ZMomentum broadening of heavy quark in a magnetized thermal QCD mediumSingh, BalbeerKurian, ManuMazumder, SurasreeMishra, HiranmayaChandra, VinodDas, Santosh K.https://repository.iitgn.ac.in/handle/123456789/53762020-05-11T11:23:46Z2020-04-01T00:00:00ZMomentum broadening of heavy quark in a magnetized thermal QCD medium
Singh, Balbeer; Kurian, Manu; Mazumder, Surasree; Mishra, Hiranmaya; Chandra, Vinod; Das, Santosh K.
Anisotropic momentum diffusion and the drag coefficients of heavy quarks have been computed in a strongly magnetized quark-gluon plasma beyond the static limit within the framework of Langevin dynamics. Depending on the orientation of the motion of the heavy quark with respect to the direction of the magnetic field, five components of the heavy quark momentum diffusion coefficients have been estimated in the magnetized thermal medium. The current focus is on the regime M?eB?????T, M being the mass of heavy quark. The light quarks/antiquarks follow 1+1?dimensional Landau level kinematics, and heavy quark dynamics are not directly affected by the magnetic field in the medium. It is observed that for the case of heavy quark motion parallel to the magnetic field, the component of diffusion coefficient transverse both to the field and the heavy quark velocity (??TT) turns out to be dominant compared to the component longitudinal to both the field and motion (??LL), i.e., ??TT???LL. On the other hand, for heavy quark moving perpendicular to the magnetic field, the component of diffusion coefficient along the direction of the magnetic field and transverse to the heavy quark velocity is dominant in comparison to the components parallel and perpendicular to the heavy quark velocity in the plane transverse to the magnetic field, i.e., ??TL???LT???TT. Sensitivity of the various diffusion coefficients on the strength of the magnetic field and velocity of the heavy quark is also explored.
2020-04-01T00:00:00ZTopological phase transitions induced by varying topology and boundaries in the toric codeJamadagni, AmitBhattacharyya, Arpanhttps://repository.iitgn.ac.in/handle/123456789/53472020-04-27T05:22:48Z2020-04-01T00:00:00ZTopological phase transitions induced by varying topology and boundaries in the toric code
Jamadagni, Amit; Bhattacharyya, Arpan
One of the important characteristics of topological phases of matter is the topology of the underlying manifold on which they are defined. In this paper, we present the sensitivity of such phases of matter to the underlying topology, by studying the phase transitions induced due to the change in the boundary conditions. We claim that these phase transitions are accompanied by broken symmetries in the excitation space and to gain further insight we analyze various signatures like the ground state degeneracy, topological entanglement entropy while introducing the open-loop operator whose expectation value effectively captures the phase transition. Further, we extend the analysis to an open quantum setup by defining effective collapse operators, the dynamics of which cool the system to different topologically ordered steady states. We show that the phase transition between such steady states is effectively captured by the expectation value of the open-loop operator.
2020-04-01T00:00:00ZQuasinormal modes and strong cosmic censorship in the novel 4D Einstein-Gauss-Bonnet gravityMishra, Akash K.https://repository.iitgn.ac.in/handle/123456789/53302020-04-20T07:26:30Z2020-04-01T00:00:00ZQuasinormal modes and strong cosmic censorship in the novel 4D Einstein-Gauss-Bonnet gravity
Mishra, Akash K.
The fate of strong cosmic censorship is ultimately linked to the extendibility of perturbation across the Cauchy Horizon and known to be violated in the near extremal region of a charged de Sitter black hole. Similar violations can also be realized in higher curvature theories, with the strength of violation becoming stronger as compared to general relativity. In this work, we extend this analysis further to study the validity of strong cosmic censorship conjecture in the context of the novel four-dimensional Einstein Gauss-Bonnet theory with respect to both scalar and electromagnetic perturbation.
2020-04-01T00:00:00Z