We study for a class of symmetric Levy processes with state space R^n the transition density pt(x) in terms of two one-parameter families of metrics, (dt)t〉o and (δt)t〉o. The first family of metrics describes...We study for a class of symmetric Levy processes with state space R^n the transition density pt(x) in terms of two one-parameter families of metrics, (dt)t〉o and (δt)t〉o. The first family of metrics describes the diagonal term pt (0); it is induced by the characteristic exponent ψ of the Levy process by dr(x, y) = √tψ(x - y). The second and new family of metrics 6t relates to √tψ through the formula exp(-δ^2t(x,y))=F[e^-tψ/pt(0)](x-y),where Y denotes the Fourier transform. Thus we obtain the following "Gaussian" representation of the tran- sition density: pt(x) = pt(O)e^-δ^2t(x,0) where pt(O) corresponds to a volume term related to √tψ and where an "exponential" decay is governed by 5t2. This gives a complete and new geometric, intrinsic interpretation of pt(x).展开更多
文摘We study for a class of symmetric Levy processes with state space R^n the transition density pt(x) in terms of two one-parameter families of metrics, (dt)t〉o and (δt)t〉o. The first family of metrics describes the diagonal term pt (0); it is induced by the characteristic exponent ψ of the Levy process by dr(x, y) = √tψ(x - y). The second and new family of metrics 6t relates to √tψ through the formula exp(-δ^2t(x,y))=F[e^-tψ/pt(0)](x-y),where Y denotes the Fourier transform. Thus we obtain the following "Gaussian" representation of the tran- sition density: pt(x) = pt(O)e^-δ^2t(x,0) where pt(O) corresponds to a volume term related to √tψ and where an "exponential" decay is governed by 5t2. This gives a complete and new geometric, intrinsic interpretation of pt(x).