标题： 宇宙屏蔽方法中的反作用力 显示英文标题

标题： Backreaction in cosmic screening approach

摘要： 我们研究了非线性扰动对宇宙整体演化的后向效应，采用了宇宙屏蔽方法。为此，我们考虑了二阶数量标量扰动。对这些扰动进行的解析研究随后通过数值评估表明，首先，相应的平均值对弗里德曼方程的后向效应可以忽略不计；其次，引力势的二阶修正远小于一阶量。因此，在宇宙屏蔽方法中将扰动展开为小量的阶数是正确的。 显示英文摘要

摘要： We investigate the backreaction of nonlinear perturbations on the global evolution of the Universe within the cosmic screening approach. To this end, we have considered the second-order scalar perturbations. An analytical study of these perturbations followed by a numerical evaluation shows that, first, the corresponding average values have a negligible backreaction effect on the Friedmann equations and, second, the second-order correction to the gravitational potential is much less than the first-order quantity. Consequently, the expansion of perturbations into orders of smallness in the cosmic screening approach is correct.