标题： 宇宙学膨胀是否会改变局部动力学？ 显示英文标题

标题： Does the Cosmological Expansion Change Local Dynamics?

摘要： 众所周知，银河系中已知物质含量的牛顿动力学描述在加速度接近$a_0 \approx 1.2 \times 10^{-10}m/s^2$时（对于星系团稍大一些）与观测结果不一致。 暗物质情景和修改引力理论（MGT）都无法解释这种加速度尺度的存在。 受这种加速度尺度与$c H_0\approx 10^{-9} h$ $ m/s^2$ 接近的启发，我们分析了这种巧合是否可能在标量-张量和旋量-张量理论中具有宇宙学起源，对代表局部物质分布的扰动进行了详细计算，这些扰动是在宇宙学背景之上的。 然后，我们在当前哈勃常数的值的幂级数中求解这些扰动的场方程。 正如我们将看到的，对于这两种理论，幂级数中只包含哈勃常数的偶次幂，这一事实使得宇宙学膨胀对局部动力学无关紧要。 最后，我们展示了预测哈勃常数线性项的理论在局部动力学中会带来多大的差异。 显示英文摘要

摘要： It is well a known fact that the Newtonian description of dynamics within Galaxies for its known matter content is in disagreement with the observations as the acceleration approaches $a_0 \approx 1.2 \times 10^{-10}m/s^2$ (slighter larger for clusters). Both the Dark Matter scenario and Modified Gravity Theories (MGT) fails to explain the existence of such an acceleration scale. Motivated by the closeness of this acceleration scale and $c H_0\approx 10^{-9} h$ $ m/s^2$, we analyse whether this coincidence might have a Cosmological origin for scalar-tensor and spinor-tensor theories, performing detailed calculations for perturbations that represent the local matter distribution on the top of the cosmological background. Then, we solve the field equations for these perturbations in a power series in the present value of the Hubble constant. As we shall see, for both theories the power expansion contains only even powers in the Hubble constant, a fact that renders the cosmological expansion irrelevant for the local dynamics. At last, we show what a difference a theory predicting linear terms in H makes in the local dynamics.