Jm. Schwarz et R. Maimon, First-passage-time exponent for higher-order random walks: Using Levy flights - art. no. 016120, PHYS REV E, 6401(1), 2001, pp. 6120
We present a heuristic derivation of the first-passage-time exponent for th
e integral of a random walk [Y. G. Sinai, Theor. Math. Phys. 90, 219 (1992)
]. Building on this derivation, we construct an estimation scheme to unders
tand the first-passage-time exponent for the integral of the integral of a
random walk, which is numerically observed to be 0.220+/-0.001. We discuss
the implications of this estimation scheme for the nth integral of a random
walk. For completeness, we also address the n(= infinity) case. Finally, w
e explore an application of these processes to an extended, elastic object
being pulled through a random potential by a uniform applied force. In so d
oing, we demonstrate a time reparametrization freedom in the Langevin equat
ion that maps nonlinear stochastic processes into linear ones.