A fast algorithm for the energy space boson Boltzmann collision operator
نویسندگان
چکیده
Abstract. This paper introduces a fast algorithm for the energy space boson Boltzmann collision operator. Compared to the direct O(N3) calculation and the previous O(N2 logN) method [Markowich and Pareschi, 2005], the new algorithm runs in complexity O(N log N), which is optimal up to a logarithmic factor (N is the number of grid points in energy space). The basic idea is to partition the 3-D summation domain recursively into elementary shapes so that the summation within each shape becomes a special double convolution that can be computed efficiently by the fast Fourier transform. Numerical examples are presented to illustrate the efficiency and accuracy of the proposed algorithm.
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ورودعنوان ژورنال:
- Math. Comput.
دوره 84 شماره
صفحات -
تاریخ انتشار 2015