DOI: 10.68381/jca18069 ISSN: 0944-6532

An Integro-Extremization Approach for Non Coercive and Evolution Hamilton-Jacobi Equations

Sandro Zagatti

We devote the integro-extremization method to the study of the Dirichlet problem for homogeneous Hamilton-Jacobi equations

\begin{cases} F(Du)=0 & \quad \textrm{in} \quad{\Omega}\cr u(x)=\varphi(x) & \quad \textrm{for} \quad x\in \partial {\Omega}, \end{cases} { F ( D u ) = 0 in Ω u ( x ) = φ ( x ) for x ∈ ∂ Ω ,
with a particular interest for non coercive hamiltonians
F F
, and to the Cauchy-Dirichlet problem for the corresponding homogeneous time-dependent equations
\begin{cases} \frac{\partial u}{\partial t}+ F(\nabla u)=0 & \quad \textrm{in} \quad ]0,T[\times {\Omega}\cr u(0,x)=\eta(x) & \quad \textrm{for} \quad x\in{\Omega}\cr u(t,x)=\psi(x) & \quad \textrm{for} \quad (t,x)\in[0,T]\times \partial {\Omega}. \end{cases} { ∂ u ∂ t + F ( ∇ u ) = 0 in ] 0 , T [ × Ω u ( 0 , x ) = η ( x ) for x ∈ Ω u ( t , x ) = ψ ( x ) for ( t , x ) ∈ [ 0 , T ] × ∂ Ω .
We prove existence and some qualitative results for viscosity and almost everywhere solutions, under suitably convexity conditions on the hamiltonian
F F
, on the domain
\Omega Ω
and on the boundary datum, without any growth assumptions on
F F