标题： 星系团的动力学在扩展的$f(χ)$引力中的研究 显示英文标题

标题： Dynamics of clusters of galaxies with extended $f(χ)$ gravity

摘要： 本文中，我们给出了四阶摄动分析的结果，涉及引力的度规理论$f(\chi) = \chi^{3/2}$，其中$\chi$是一个合适的无量纲里奇标量。 这种模型对应于特定的$f(R)$度规引力理论，其中系统的质量被包含在引力场的作用量中。 在之前的工作中，我们已经表明，直到二阶摄动，该理论能够重现星系的平坦旋转曲线以及单个星系、星系群和星系团中的引力透镜细节。 在这里，我们在固定之前工作结果的基础上，展示该理论无需暗物质即可通过直到四阶近似的度规系数重现12个钱德拉 X 射线星系团的动力学质量。 从这个意义上讲，我们计算了$f(\chi)$度规理论的第一个相对论修正，并将其应用于拟合星系团的动力学质量。 显示英文摘要

摘要： In this article, we present the results of a fourth order perturbation analysis of the metric theory of gravity $f(\chi) = \chi^{3/2}$, with $\chi$ a suitable dimensionless Ricci scalar. Such model corresponds to a specific $f(R)$ metric theory of gravity, where the mass of the system is included into the gravitational field's action. In previous works we have shown that, up to the second order in perturbations, this theory reproduces flat rotation curves of galaxies and the details of the gravitational lensing in individual, groups and clusters of galaxies. Here, leaving fixed the results from our previous works, we show that the theory reproduces the dynamical masses of 12 Chandra X-ray galaxy clusters, without the need of dark matter, through the metric coefficients up to the fourth order of approximation. In this sense, we calculate the first relativistic correction of the $f(\chi)$ metric theory and apply it to fit the dynamical masses of the clusters of galaxies.