We study the emission of large-scales wavelength space–time waves during the inflationary expansion of the universe, produced by back-reaction effects. As an example, we study an inflationary model with variable time scale, where the scale factor of the universe grows as a power of time. The coarse-grained field to describe space–time waves is defined by using the Levy distribution, on the wavenumber space. The evolution for the norm of these waves on cosmological scales is calculated, and it is shown that decreases with time.

中文翻译：

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带有时变宇宙学参数的大尺度时空波

我们研究了由反作用效应产生的宇宙膨胀膨胀期间大尺度波长时空波的发射。例如，我们研究了具有可变时间尺度的通货膨胀模型，其中宇宙的尺度因子随着时间的增长而增长。使用波数空间上的Levy分布定义了描述时空波的粗粒度场。计算了这些波的规范在宇宙尺度上的演化，并显示其随时间减小。