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  • Das, Saurya; Shankaranarayanan, S.; Sur, Sourav (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeMax-Planck-Institut für Gravitationphysikhttps://doi.org/10.1139/p07-183, 2015-12-15)
    Considering the entanglement between quantum field degrees of freedom inside and outside the horizon as a plausible source of black hole entropy, we address the question: where are the degrees of freedom that give rise ...
  • Sur, Sourav; Das, Saurya (Arts and ScienceDepartment of PhysicsUniversity of Lethbridgehttps://doi.org/10.1088/1475-7516/2009/01/007, 2015-12-15)
    We investigate models of dark energy with purely kinetic multiple k- essence sources that allow for the crossing of the phantom divide line, without violating the conditions of stability. It is known that with more than ...
  • Alberto, Pedro; Das, Saurya; Vagenas, Elias C. (Arts and ScienceDepartment of Physics and AstronomyUniversidade de CoimbraUniversity of LethbridgeAcademy of Athenshttps://doi.org/10.1016/j.physleta.2011.02.030, 2015-12-15)
    We generalize the work of Alberto, Fiolhais and Gil and solve the problem of a Dirac particle confined in a 3-dimensional box. The non-relativistic and ultra-relativistic limits are considered and it is shown that the ...
  • Braunstein, Samuel L.; Das, Saurya; Shankaranarayanan, S. (Arts and ScienceDepartment of PhysicsUniversity of YorkUniversity of LethbridgeIndian Institute of Science Education and Research, 2015-12-15)
    It has long been conjectured that the entropy of quantum fields across boundaries scales as the boundary area. This conjecture has not been easy to test in spacetime dimensions greater than four because of divergences ...
  • Das, Saurya; Patitsas, Steve (Arts and ScienceDepartment of Physics and AstronomyUniversity of Lethbridgehttps://doi.org/10.1103/PhysRevD.87.107101, 2015-12-15)
    The extremely small accelerations of objects required for the the onset of modified Newtonian dynamics, or MOND, makes testing the hypothesis in conventional terrestrial laboratories virtually impossible. This is due to ...
  • Das, Saurya; Vagenas, Elias C. (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeAcademy of Athenshttps://doi.org/10.1103/PhysRevLett.104.119002, 2015-12-15)
    A reply to the Comment by M. M. Ettefaghi and S. M. Fazeli
  • Das, Saurya; Dey, Anindya; SenGupta, Soumitra (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeHarish-Chandra Research InstituteIndian Association for the Cultivation of Sciencehttps://doi.org/10.1088/0264-9381/23/20/L01, 2015-12-16)
    We re-examine the fine tuning problem of the Higgs mass, when an antisymmetric two form Kalb-Ramond (KR) field is present in the bulk of a Randall-Sundrum (RS) braneworld. Taking into account the back-reaction of the KR ...
  • Sur, Sourav; Das, Saurya; SenGupta, Soumitra (Arts and ScienceDepartment of PhysicsInstitute of PhysicsUniversity of LethbridgeIndian Association for the Cultivation of Science, 2015-12-16)
    We study generic Einstein-Maxwell-Kalb-Ramond-dilaton actions, and derive conditions under which they give rise to static, spherically symmetric black hole solutions. We obtain new asymptotically flat and non-flat black ...
  • Das, Saurya; Mukhopadhyay, Himan; Ramadevi, P. (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeIndian Institute of Technologyhttps://doi.org/10.1088/0264-9381/22/2/015, 2015-12-16)
    The reduced phase space formalism for quantising black holes has recently been extended to find the area and angular momentum spectra of four dimensional Kerr black holes. We extend this further to rotating black holes ...
  • Das, Saurya; Shankaranarayanan, S. (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeMax-Planck-Institut für Gravitationphysikhttps://doi.org/10.1088/1742-6596/68/1/012015, 2015-12-16)
    We review aspects of black hole thermodynamics, and show how entanglement of a quantum field between the inside and outside of a horizon can account for the areaproportionality of black hole entropy, provided the field ...
  • Das, Saurya (Arts and ScienceDepartment of PhysicsUniversity of Lethbridgehttps://www.ias.ac.in/article/fulltext/pram/063/04/0797-0815, 2015-12-16)
    We review some recent advances in black hole thermodynamics, including statistical mechanical origins of black hole entropy and its leading order corrections, from the viewpoints of various quantum gravity theories. We ...
  • Balasubramanian, Venkat; Das, Saurya; Vagenas, Elias C. (Arts and ScienceDepartment of Physics and AstronomyUniversity of Western OntarioUniversity of LethbridgeKuwait Universityhttps://doi.org/10.1016/j.aop.2015.04.033, 2015-12-16)
    In this work we explore the self-adjointness of the GUP-modified momentum and Hamiltonian oper- ators over different domains. In particular, we utilize the theorem by von-Newmann for symmetric operators in order to ...
  • Das, Saurya; Vagenas, Elias C.; Ali, Ahmed Farag (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeAcademy of Athens, 2015-12-22)
    Various theories of Quantum Gravity predict modifications of the Heisenberg Uncertainty Prin- ciple near the Planck scale to a so-called Generalized Uncertainty Principle (GUP). In some recent papers, we showed that the ...
  • Das, Saurya; Vagenas, Elias C. (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeAcademy of Athenshttps://doi.org/10.1209/0295-5075/96/50005, 2015-12-22)
    We argue that a quantum aether is consistent with the principle of relativity and can provide an economical way of having an invariant quantum gravity or Planck scale. We also show that it may change the effective scale ...
  • Das, Saurya (Arts and ScienceDepartment of PhysicsUniversity of Lethbridgehttps://doi.org/10.1103/PhysRevD.89.084068, 2015-12-22)
    We compute quantum corrections to the Raychaudhuri equation by replacing classical geodesics with quantal (Bohmian) trajectories, and show that they prevent focusing of geodesics, and the formation of conjugate points. ...
  • Ali, Ahmed Farag; Das, Saurya; Vagenas, Elias C. (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeAcademy of Athenshttps://doi.org/10.1103/PhysRevD.84.044013, 2015-12-22)
    Attempts to formulate a quantum theory of gravitation are collectively known as quantum gravity. Various approaches to quantum gravity such as string theory and loop quantum gravity, as well as black hole physics and ...
  • Das, Saurya; Maity, Debaprasad; SenGupta, Soumitra (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeThe Institute of Mathematical Sciences (India)Indian Association for the Cultivation of Science, 2015-12-22)
    We consider a generalized Randall Sundrum (RS) brane world scenario with a cosmological constant induced on the visible brane. We show that for < 0, resolution of the hierarchy problem requires an upper bound on the ...
  • Das, Saurya; Vagenas, Elias C. (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeAcademy of Athenshttps://doi.org/10.1103/PhysRevLett.101.221301, 2015-12-22)
    We show that the existence of a minimum measurable length and the related Generalized Uncertainty Principle (GUP), predicted by theories of Quantum Gravity, influence all quantum Hamiltonians. Thus, they predict quantum ...
  • Das, Saurya; Shankaranarayanan, S.; Sur, Sourav (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeMax-Planck-Institut für Gravitationphysikhttps://doi.org/10.1103/PhysRevD.77.064013, 2015-12-22)
    We re-examine the idea that the origin of black-hole entropy may lie in the entanglement of quantum fields between inside and outside of the horizon. Motivated by the observation that certain modes of gravitational ...
  • Das, Saurya; Shankaranarayanan, S. (Arts and ScienceDepartment of PhysicsUniversity of LethbridgeThe Abdus Salam International Centre for Theoretical Physicshttps://doi.org/10.1088/0264-9381/22/3/L01, 2015-12-23)
    We compute the high frequency quasi-normal modes (QNM) for scalar perturbations of spherically symmetric single horizon black-holes in (D+2)-space-time dimensions with generic curvature singularities and having metrics ...