The Absence of Positive Global Periodic Solution of a Second-Order Semi Linear Parabolic Equation With Time-Periodic Coefficients.

Second order semilinear parabolic equation ∂u/ ∂t = div(A(x, t)∇u) + h(x, t, u) with time-periodic coefficients is considered in domain Ω × (−∞, +∞), where Ω is the exterior of a compact set in Rn x. Depending on the behavior of the function h(x, t, u) at infinity, the conditions are found under which the positive periodic solution does not exist. [ABSTRACT FROM AUTHOR]