Stackelberg-Nash strategy for the null controllability of semilinear degenerate equations in non-cylindrical domains
Alfredo S. Gamboa, Juan Limaco, Luis P. Yapu
TL;DR
This work addresses local null controllability for a semilinear degenerate parabolic equation defined on a moving (non-cylindrical) domain, where the diffusion $a(x)$ vanishes at the boundary and behaves like $a(x)\sim x^{\alpha}$ with $\alpha\in(0,1)$. It adopts a Stackelberg-Nash hierarchy with a leader $h$ and two followers $v^1,v^2$, transforming the moving domain to a cylindrical one via a time-dependent diffeomorphism, and proving null controllability through Carleman estimates for the resulting non-autonomous degenerate system and Liusternik's inverse function theorem for the nonlinear problem. The authors establish Nash quasi-equilibria for the followers, derive the associated optimality system, and show that large follower penalties yield a true Nash equilibrium; they also prove global null controllability for the linearized system with explicit weighted estimates and then obtain local controllability for the nonlinear system. These results extend controllability theory to degenerate parabolic equations in moving domains and provide a rigorous framework for hierarchical control under non-autonomous, time-varying diffusion. The work has potential implications for diffusion processes with boundary degeneration in evolving spatial domains and for applications requiring multi-level control structures.
Abstract
In this paper we use a Stackelberg-Nash strategy to show the local null controllability of a semilinear parabolic equation in one-dimension defined in a non-cylindrical domain where the diffusion coefficient degenerates at one point of the boundary. The linearized degenerated system is treated using a Carleman inequality for degenerated non-autonomous systems proved by the autors in [19] and the local controllability of the semilinear system is obtained using Liusterniks inverse function theorem.
