Concentration of the Dissolved Gas
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Let us consider a gas dissolved in a liquid. The solution was initially in an equilibrium state at temperature $T$ and pressure $P_0$. The concentration of the dissolved gas in the solution under such conditions will be denoted as $n_0$. Then we instantly relieve the external pressure to value $\Pi$ in such way that solution becomes supersaturated. The temperature and volume of the solution remain the same, thus value $n_0$ still serves for the dissolved gas concentration.

It is more convenient to express the state of the solution in terms of dimensionless variables: supersaturation $\zeta$ and gas solubility $s$ defined here via $$\label{zeta}
\zeta \equiv \frac{n_0 - n_\infty}{n_\infty}\; ,$$ $$\label{s}
s \equiv \frac{k T n_\infty}{\Pi}\; ,$$ where $n_{\infty}$ is the equilibrium concentration of dissolved gas at the external pressure $\Pi$, $k$ is the Boltzmann’s constant.

When some time passes after the pressure drop, a gas bubble nucleates and begins growing regularly. Following \[\[Chernov-2004\]\] we assume that the bubble is in mechanical equilibrium with the solution, and its dynamics is governed only by diffusion process. This assumption will be discussed in Appendix A. The radius of the bubble will be denoted as $R$. We consider 