مشخصات پژوهش

صفحه نخست /Emergent universe in the ...
عنوان
Emergent universe in the braneworld scenario
نوع پژوهش مقاله چاپ شده
کلیدواژه‌ها
braneworld scenario
چکیده
According to Padmanabhan’s proposal, the dif-ference between the surface degrees of freedom and the bulk degrees of freedom in a region of space may result in the acceleration of Universe expansion through the relation  V /t = N sur − N bulk whereN bulk and N sur are referred to the degrees of freedom related to the matter and energy con-tent inside the bulk and surface area, respectively (Padman-abhan, arXiv:1206.4916v1 , 2012 ). In this paper, we study the dynamical effect of the extrinsic geometrical embedding of an arbitrary four-dimensional brane in a higher-dimensional bulk space and investigate the corresponding degrees of free-dom. Considering the modification of the Friedmann equa-tions arising from a general braneworld scenario, we obtain a correction term in Padmanabhan’s relation, denoting the number of degrees of freedom related to the extrinsic geom-etry of the brane embedded in higher-dimensional spacetime as  V /t = N sur − N bulk − N extr where N extr is for the degree of freedom related to the extrinsic geometry of the brane, whileN sur and N bulk are defined as before. Finally, we study the validity of the first and second laws of thermo-dynamics for this general braneworld scenario in the state of thermal equilibrium and in the presence of confined matter fields to the brane with the induced geometric matter fields
پژوهشگران یعقوب حیدرزاده (نفر اول)، حامد هادی (نفر دوم)، فرهاد دارابی (نفر سوم)، احمد شیخی (نفر چهارم)