2 problems

Let $(\Box_{N+1}+u(x))\varphi=0$ be a hyperbolic equation, and suppose that its sequence of Hadamard coefficients terminates. A locus configuration is a configuration of hyperplane…

Let $u(x_1,\ldots,x_n)$ be a potential and consider the hyperbolic equation … A potential is called huygensian when the corresponding equation satisfies Huygens' Principle. Complet…