t^2$ and $1/\m t_l \simeq (8\r 
(t_l 
)/\m)^{1/2}$ Taking $\r (t_l )/\m \sim 0.1\div 0.001$ and $\m\sim 10^{-12} GeV$, we have $1/\m t_l\simeq 0.9\div 0.09$ and $T_l \sim (5.1\div 1.6)\cdot 10^2 GeV$. For $\r (t_l )/\m \sim 0.1$ we obtain ł[f14]{} I\_[04]{}-20.0048 .In the same way, calculating $I_{44}$, we obtain ł[f18]{} I\_[44]{}=\_[t\_l]{}\^t dt’Ţ\_[44]{}(t’ )(2(t’ ))\^[1/2]{}a\^[-4]{} (0,t’) = (-), where $$\k^2 T_{44} =A_{44}\r^2 =\f{3\, A\,\zeta (9/2)\zeta (7/2)}{4
\pi^4}\left(\f{180}{g_* \pi^2}\right)^2\r^2
\simeq 0.10 \r^2
.$$ This yields ł[f15]{} I\_[44]{}20.00094.

Graviton emission in the bulk and nucleosynthesis
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Graviton emission in the period of late cosmology
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Let us compare abundances of ${}^4 He$ produced in primordial nucleosynthesis calculated in the models with and without account of the graviton emission in the bulk. We consider the radiation-dominated period of late cosmology, in which production of gravitons is sufficiently intensive. In the period of late cosmology the leading approximation of the Friedmann equation coincides with the standard cosmological model.

We estimate the effect of the graviton emission on nucleosynthesis by solving Friedmann equation perturbatively keeping in the generalized Friedmann equation (\[14a\]) the term linear in the radiation energy density and the terms containing the bulk energy-momentum tensor. The Weyl radiation term and the term quadratic 