We look at estimates for the Green’s function of time-fractional evolution equations of the form
, where
is a Caputo-type time-fractional derivative, depending on a Lévy kernel
with
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We look at estimates for the Green’s function of time-fractional evolution equations of the form
, where
is a Caputo-type time-fractional derivative, depending on a Lévy kernel
with variable coefficients, which is comparable to
for
, and
L is an operator acting on the spatial variable. First, we obtain global two-sided estimates for the Green’s function of
in the case that
L is a second order elliptic operator in divergence form. Secondly, we obtain global upper bounds for the Green’s function of
where
is a pseudo-differential operator with constant coefficients that is homogeneous of order
. Thirdly, we obtain local two-sided estimates for the Green’s function of
where
L is a more general non-degenerate second order elliptic operator. Finally we look at the case of stable-like operator, extending the second result from a constant coefficient to variable coefficients. In each case, we also estimate the spatial derivatives of the Green’s functions. To obtain these bounds we use a particular form of the Mittag-Leffler functions, which allow us to use directly known estimates for the Green’s functions associated with
L and
, as well as estimates for stable densities. These estimates then allow us to estimate the solutions to a wide class of problems of the form
, where
is a Caputo-type operator with variable coefficients.
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