标题： 广义Brans-Dicke参数在超反弹场景中的演化 显示英文标题

标题： Evolution of Generalized Brans-Dicke parameter within a Superbounce scenario

摘要： 我们研究了一个在布兰斯-迪克（BD）理论设定下的超级反弹场景。 BD参数被认为是时间相关的，并假定随着布兰斯-迪克标量场演化。 在超级反弹场景中，如果激进相持续到那时，模型会在对应大挤压的时期反弹。 在给定的超级反弹场景中，我们研究了不同状态方程下BD参数的演化。 我们选择了一个具有沿x轴轴对称的轴对称度规。 该度规被假定包含各向异性膨胀效应。 研究了不对称膨胀和各向异性参数对BD参数演化部分和非演化部分的影响。 显示英文摘要

摘要： We have studied a superbounce scenario in a set up of Brans-Dicke (BD) theory. The BD parameter is considered to be time dependent and is assumed to evolve with the Brans-Dicke scalar field. In the superbounce scenario, the model bounces at an epoch corresponding to a Big Crunch provided the ekpyrotic phase continues until that time. Within the given superbounce scenario, we investigate the evolution of the BD parameter for different equations of state. We chose an axially symmetric metric that has an axial symmetry along the x-axis. The metric is assumed to incorporate an anisotropic expansion effect. The effect of asymmetric expansion and the anisotropic parameter on the evolving and the non-evolving part of the BD parameter is investigated.