Global existence of solutions to semi-linear σ-evolution equations with
different damping types in Lq framework
Abstract
In this paper, we would like to study the Cauchy problem for linear
σ-evolution equations with mixing the parabolic like damping term
corresponding to σ 1 ∈ [ 0 , σ / 2 ) and the σ-evolution like
damping corresponding to σ 2 ∈ ( σ / 2 , σ ] . The main goals are on
the one hand to conclude some estimates for solutions and their
derivatives in the L q setting, with any q∈[1 ,∞], by
developing the theory of modified Bessel functions effectively to
control Fourier multipliers appearing the solution representation
formula in a competition between these two kinds of damping. On the
other hand, we are going to prove the global (in time) existence of
small data Sobolev solutions in the treatment of the corresponding
semi-linear equations by applying ( L m ∩ L q ) - L q and L q - L q
estimates, with q∈(1 ,∞) and m∈[1 ,q),
from the linear models. Thanks to flexible choices of parameters
q,m and even suitably required regularities, one recognizes that
not only some restrictions for power exponents can be relaxed, but also
they allow us to conclude an existence result for global solutions with
arbitrarily small regularity in terms of dealing with the semi-linear
equations.