Gauge-invariant perturbations in a flat FRW universe.
نویسندگان
چکیده
Starting out with new deenitions for the gauge-invariant perturbations in energy density and particle number density, evolution equations for these quantities are derived which are manifestly gauge-invariant. In the case of vanishing pressure, these equations are identical to Poisson's equation. This fact is in contrast to what is found in earlier treatments based on other dee-nitions.
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عنوان ژورنال:
- Physical review. D, Particles and fields
دوره 54 12 شماره
صفحات -
تاریخ انتشار 1996