Eigenfunction Decay For the Neumann Laplacian on Horn-Like Domains
Julian K. Edward · Canadian Mathematical Bulletin · 2000
Abstract The growth properties at infinity for eigenfunctions corresponding to embedded eigenvalues of the Neumann Laplacian on horn-like domains are studied. For domains that pinch at polynomial rate, it is shown that the eigenfunctions vanish at infinity faster than the reciprocal of any polynomial. For a class of domains that pinch at an exponential rate, weaker, L2 bounds are proven. A corollary is that eigenvalues can accumulate only at zero or infinity.