论文标题
重新加热期间状态参数方程的时间演变
Accounting for the time evolution of the equation of state parameter during reheating
论文作者
论文摘要
宇宙学的重要参数之一是表征驱动宇宙扩展的来源状态方程（EOS）的参数。以辐射，物质或标量场为主的时期，无论是直接还是间接探测，都可以以该参数的唯一值来表征。但是，再加热过程中的EOS参数 - - 一个阶段后的通货膨胀率应该迅速解散我们的宇宙 - 仍然有待令人满意地理解。为了避免在加热过程中定义瞬时EOS参数的复杂性，通常会考虑在重新加热期间的一个有效参数$ W_ \ Mathrm {eff} $（这是EOS参数的平均值）。 $ w_ \ mathrm {eff} $的值通常被任意选择为$ -1/3 \ leq w_ \ mathrm {eff} \ leq 1 $。在这项工作中，我们考虑重新加热期间EOS参数的时间演变，并将其与通货膨胀势$ V（ϕ）$相关联，其表现为最低限度的$ ϕ^p $，该提案可以应用于广泛的通货膨胀模型。我们发现，鉴于索引$ p $，有效的EOS参数$ w _ {\ rm eff} $是唯一确定的。我们讨论对加热温度及其含义的相应影响。
One of the important parameters in cosmology is the parameter characterizing the equation of state (EoS) of the sources driving the cosmic expansion. Epochs that are dominated by radiation, matter, or scalar fields, whether they are probed either directly or indirectly, can be characterised by a unique value of this parameter. However, the EoS parameter during reheating---a phase succeeding inflation which is supposed to rapidly defrost our universe---remains to be understood satisfactorily. In order to circumvent the complexity of defining an instantaneous EoS parameter during reheating, an effective parameter $w_\mathrm{eff}$, which is an average of the EoS parameter over the duration of reheating, is usually considered. The value of $w_\mathrm{eff}$ is often chosen arbitrarily to lie in the range $-1/3 \leq w_\mathrm{eff} \leq 1$. In this work, we consider the time evolution of the EoS parameter during reheating and relate it to inflationary potentials $V(ϕ)$ that behave as $ϕ^p$ around the minimum, a proposal which can be applied to a wide class of inflationary models. We find that, given the index $p$, the effective EoS parameter $w_{\rm eff}$ is determined uniquely. We discuss the corresponding effects on the reheating temperature and its implications.
