  A general class of heat operators over non-archimedean local fields acting on
$L_2$-function spaces on affinoid domains in the local field are developed.
$L_2$-spaces and integral operators invariant under the action of a
non-archimedean Schottky group are constructed in order to have nice function
spaces and operators on Mumford curves. General wavelets are constructed which,
together with functions coming from certain graph Laplacian eigenvectors,
diagonalise these operators. The corresponding Cauchy problems for the heat
equations with these operators are solved in the affirmative, and properties of
wavelet eigenvalues and the spectral gaps of the operators on Mumford curves
are studied.
