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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Alzheimer random walk model: Two previously overlooked diffusion regimes

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Autor(es):
Cressoni, J. C. [1, 2] ; Viswanathan, G. M. [3, 2] ; Ferreira, A. S. [4] ; da Silva, M. A. A. [1]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, FCFRP, Dept Fis & Quim, BR-14040903 Ribeirao Preto, SP - Brazil
[2] Univ Fed Alagoas, Inst Fis, BR-57072970 Maceio, AL - Brazil
[3] Univ Fed Rio Grande do Norte, Dept Fis Teor & Expt, BR-59078900 Natal, RN - Brazil
[4] Univ Fed Pernambuco, Dept Fis, BR-50670901 Recife, PE - Brazil
Número total de Afiliações: 4
Tipo de documento: Artigo Científico
Fonte: Physical Review E; v. 86, n. 4, 1 OCT 2 2012.
Citações Web of Science: 4
Resumo

A non-Markovian one-dimensional random walk model is studied with emphasis on the phase-diagram, showing all the diffusion regimes, along with the exactly determined critical lines. The model, known as the Alzheimer walk, is endowed with memory-controlled diffusion, responsible for the model's long-range correlations, and is characterized by a rich variety of diffusive regimes. The importance of this model is that superdiffusion arises due not to memory per se, but rather also due to loss of memory. The recently reported numerically and analytically estimated values for the Hurst exponent are hereby reviewed. We report the finding of two, previously overlooked, phases, namely, evanescent log-periodic diffusion and log-periodic diffusion with escape, both with Hurst exponent H = 1/2. In the former, the log-periodicity gets damped, whereas in the latter the first moment diverges. These phases further enrich the already intricate phase diagram. The results are discussed in the context of phase transitions, aging phenomena, and symmetry breaking. (AU)

Processo FAPESP: 11/13685-6 - Modelagem analítica e computacional de sistemas difusivos
Beneficiário:Marco Antonio Alves da Silva
Linha de fomento: Auxílio à Pesquisa - Pesquisador Visitante - Brasil
Processo FAPESP: 11/06757-0 - Processos difusivos: caminhantes aleatórios com memória
Beneficiário:Marco Antonio Alves da Silva
Linha de fomento: Auxílio à Pesquisa - Regular