Blow-up of the 3-D compressible Navier-Stokes equations for monatomic gases
Feng Shao, Dongyi Wei, Shumao Wang, Zhifei Zhang
TL;DR
The paper resolves the degenerate case $\gamma=5/3$ for the 3-D isentropic compressible Navier–Stokes equations by combining a construction of smooth self-similar Euler imploding profiles with a nonlinear framework (CLGSSS) to produce non-radial Navier–Stokes blow-up data. It first proves the existence of a discrete sequence of smooth radially symmetric self-similar Euler profiles $(\mathbf U_E,S_E)$ corresponding to exponents $r_n$ with $r_n<3-\sqrt{3}$ and $r_n\to3-\sqrt{3}$, and then extends these to finite-time blow-up solutions of the 3-D Navier–Stokes system with $\nu=1$ and non-radial perturbations, via a coercivity/repulsivity analysis of an autonomous ODE system obtained from the self-similar reduction. A computer-assisted verification confirms a key non-degeneracy quantity $\mathcal S_\infty>0$, enabling the construction, and yielding explicit asymptotics for the blow-up profiles. The results advance the Merle–Raphaël–Rodnianski–Szeftel program to the physically important monatomic gas case, establishing the existence of infinitely many smooth blow-up solutions in 3-D with self-similar structure for $\gamma=5/3$ and providing new insight into front-compression mechanisms in compressible fluids.
Abstract
In this paper, we prove the blow-up of the $3$-D isentropic compressible Navier-Stokes equations for the adiabatic exponent $γ=5/3$, which corresponds to the law of monatomic gases. This is the degenerate case in the sense of [Merle, Raphaël, Rodnianski and Szeftel, Ann. of Math. (2), 196 (2022), 567-778; Ann. of Math. (2), 196 (2022), 779-889]. Motivated by these breakthrough works, we first establish the existence of a sequence of smooth, self-similar imploding solutions to the compressible Euler equations for $γ=5/3$. Subsequently, we utilize these self-similar profiles to construct smooth, asymptotically self-similar blow-up solutions to the compressible Navier-Stokes equations for monatomic gases.
