Abstract

In this paper, we use the solution of the collapse model presented in a previous paper by Del Popolo to obtain more precise estimates on the turn-around radius (TAR) (namely the radius at which the expansion is divided into the region of recollapse from the material continuing its motion following the Hubble flow), R₀ (note that in this paper TAR or R₀ represent the turn-around radius, as specified in the previous footnote), and structure mass, M, of the Local Group, M81, NGC 253, IC 342, Cen A/M83, and to the Virgo clusters. To this aim, similarly to Peirani and Pacheco, we found a relationship between the velocity, \({v}\), and radius, R, depending on the Hubble parameter, and structure mass, M, and fitted them to data of the Local Group, M81, NGC 253, IC 342, Cen A/M83, and to the Virgo clusters obtained by Peirani and Pacheco. In this way, we obtained optimized values of the mass, the Hubble constant, and R₀, of the objects studied. Similarly to the quoted Del Popolo’s paper, the Lemaitre–Tolman model took into account the cosmological constant, angular momentum and dynamical friction. The fit gives values of the masses 30–40% larger than the \({v}\)–R relationship obtained from the standard Lemaitre–Tolman (LT) model (not taking account nor cosmological constant, angular momentum, or dynamical friction). Differently from mass, the Hubble parameter becomes smaller with respect to the LT model, when angular momentum, and dynamical friction are introduced. This is in agreement with Peirani and Pacheco, who improved the standard Lemaitre–Tolman model taking into account the cosmological constant. After determining, the optimized values of the TAR, R₀, and mass, M, of the studied objects, we put constraints to the dark energy equation of state parameter, w.

中文翻译：

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关于角动量和动摩擦对结构形成的影响。二。转弯和结构质量

摘要

在本文中，我们使用Del Popolo在前一篇论文中提出的坍塌模型的解决方案来获得更精确的转弯半径（TAR）估算值（即，展开时将其划分为从中重新塌陷的区域的半径）材料，沿哈勃流动继续运动），R ₀（注意，在本文中TAR或R ₀表示转弯半径，如上一个脚注中所述），以及局部组M81的结构质量M，NGC 253，IC 342，Cen A / M83以及处女座星团。为此，类似于Peirani和Pacheco，我们发现了速度\（{v} \）与半径R之间的关系。，取决于哈勃参数和结构质量M，并将它们拟合到本地组M81，NGC 253，IC 342，Cen A / M83的数据以及Peirani和Pacheco获得的处女座星团。通过这种方式，我们获得了所研究对象的质量，哈勃常数和R _0的优化值。与引用的Del Popolo论文相似，Lemaitre-Tolman模型考虑了宇宙学常数，角动量和动力摩擦。拟合给出的质量值比\（{v} \） – R大30–40％从标准Lemaitre-Tolman（LT）模型获得的关系（不考虑宇宙常数，角动量或动力摩擦）。与质量不同，引入角动量和动摩擦时，哈勃参数相对于LT模型变得更小。这与佩伊拉尼（Peirani）和帕切科（Pacheco）一致，他们考虑了宇宙学常数，改进了标准的勒梅特-托尔曼（Lemaitre-Tolman）模型。确定了被研究物体的TAR，R ₀和质量M的最佳值后，我们对状态参数的暗能量方程w施加了约束。