论文标题
深色能量各向异性应力对物质功率谱的影响
Effects of Dark Energy anisotropic stress on the matter power spectrum
论文作者
论文摘要
我们研究了暗能量（DE）各向异性应力对物质功率谱（PS）特征的影响。我们采用参数化的后曼尼亚（PPF）形式主义来模仿有效的DE，并通过控制其整体幅度（$ g_0 $）和过渡量表（$ c_g $）的两参数方程来对其各向异性应力特性进行建模。对于背景宇宙学，我们考虑了模拟DE的不同状态方程式，包括常数$ W_0 $参数，以及提供解冻（CPL）和冻结（NCPL）行为的模型。我们首先使用万神殿，bao，$ h_0 $和cmb planck数据来限制这些参数。然后，我们分析了这些参数在线性PS中所起的作用。为了使各向异性压力不要引起大于$ 10 \％$和$ 5 \％$相对于$λ$ CDM PS $ k \ sim 0.01 \，h/\ text {mpc} $ <g_0 <0.16 $，$ 0 \ leq c_g^2 <0.01 $。此外，我们使用标准扰动理论在真实和红移空间中对PS进行了领先的非线性校正，这表明相对于$λ$ CDM的差异得到了增强，尤其是对于四极杆和己二核RSD Multiles。
We study the effects of dark energy (DE) anisotropic stress on features of the matter power spectrum (PS). We employ the Parametrized Post-Friedmannian (PPF) formalism to emulate an effective DE, and model its anisotropic stress properties through a two-parameter equation that governs its overall amplitude ($g_0$) and transition scale ($c_g$). For the background cosmology, we consider different equations of state to model DE including a constant $w_0$ parameter, and models that provide thawing (CPL) and freezing (nCPL) behaviors. We first constrain these parameters by using the Pantheon, BAO, $H_0$ and CMB Planck data. Then, we analyze the role played by these parameters in the linear PS. In order for the anisotropic stress not to provoke deviations larger than $10\%$ and $5\%$ with respect to the $Λ$CDM PS at $k \sim 0.01 \,h/\text{Mpc}$, the parameters have to be in the range $-0.30< g_0 < 0.32$, $0 \leq c_g^2 < 0.01$ and $-0.15 < g_0 < 0.16$, $0 \leq c_g^2 < 0.01$, respectively. Additionally, we compute the leading nonlinear corrections to the PS using standard perturbation theory in real and redshift space, showing that the differences with respect to the $Λ$CDM are enhanced, especially for the quadrupole and hexadecapole RSD multipoles.
