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We show how to improve the finite element method on the Sierpinski gasket (SG) to allow arbitrary partitions of the space. We use this method to study numerically solutions of the Schrödinger equation with well-type potentials, and the wave equation. We also show that Fourier series-type expansions on SG of functions with jump discontinuities appear to exhibit a self-similar Gibbs' phenomenon.

We show that the restriction of an eigenfunction of the Laplacian on the Sierpinski Gasket (SG) to any segment inside the SG is monotone on finite pieces, i.e. there is a subdivision of the segment, such that the function is monotone on all subintervals.

Consider a family of bounded domains Ω_t in the plane (or more generally any Euclidean space) that depend analytically on the parameter t, and consider the ordinary Neumann Laplacian Δ_t on each of them. Then we can organize all the eigenfunctions into continuous families with eigenvalues also varying continuously with t, although the relative sizes of the eigenvalues will change with t at crossings where . We call these families homotopies of eigenfunctions. We study two explicit examples. The first example has Ω₀ equal to a square and Ω₁ equal to a circle; in both cases the eigenfunctions are known explicitly, so our homotopies connect these two explicit families. In the second example we approximate the Sierpinski carpet starting with a square, and we continuously delete subsquares of varying sizes. (Data available in full at ).

We introduce a family of post-critically finite fractal trees indexed by the number of branches they possess. Then we produce a Laplacian operator on graph approximations to these fractals and use spectral decimation to describe the spectrum of the Laplacian on these trees. Lastly we consider the behavior of the spectrum as the number of branches increases.

Much is known in the analysis of a finitely ramified self-similar fractal when the fractal has a harmonic structure: a Dirichlet form which respects the self-similarity of a fractal. What is still an open question is when such a structure exists in general. In this paper, we introduce two fractals, the fractalina and the pillow, and compute their resistance scaling factor. This is the factor which dictates how the Dirichlet form scales with the self-similarity of the fractal. By knowing this factor one can compute the harmonic structure on the fractal. The fractalina has scaling factor , and the pillow fractal has scaling factor .