论文标题
宇宙加速度在扩展的Brans-Dicke-Higgs理论中
Cosmic Acceleration in an Extended Brans-Dicke-Higgs Theory
论文作者
论文摘要
我们考虑了一种扩展的标量探测重力理论，其中该动作具有两个相互作用的标量场，这是一个Brans-Dicke场，它使有效的牛顿常数成为坐标的函数和HIGGS场，该函数与Lagrangian具有导数且非衍生的相互作用。两个标量场之间存在非平凡的相互作用，这决定了不同时代不同标量场的主导地位。我们调查了这种设置是否可以描述近期从减速的平稳过渡之前的后期宇宙加速度。从宇宙学重建技术中，我们发现标量曲线是红移的函数。我们使用观察数据从马尔可夫链蒙特卡洛分析中找到对模型参数的约束。研究了宇宙的有效状态，物质密度对比度和热力学平衡的演变，并讨论了它们的意义与LCDM宇宙学相比。
We consider an extended scalar-tensor theory of gravity where the action has two interacting scalar fields, a Brans-Dicke field which makes the effective Newtonian constant a function of coordinates and a Higgs field which has derivative and non-derivative interaction with the lagrangian. There is a non-trivial interaction between the two scalar fields which dictates the dominance of different scalar fields in different era. We investigate if this setup can describe a late-time cosmic acceleration preceded by a smooth transition from deceleration in recent past. From a cosmological reconstruction technique we find the scalar profiles as a function of redshift. We find the constraints on the model parameters from a Markov Chain Monte Carlo analysis using observational data. Evolution of an effective equation of state, matter density contrast and thermodynamic equilibrium of the universe are studied and their significance in comparison with a LCDM cosmology is discussed.
