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arXiv · 1703.06711

Nonlinear Perturbation of a Noisy Hamiltonian Lattice Field Model: Universality Persistence

Cédric Bernardin·Patricia Gonçalves·Milton Jara·Marielle Simon
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Abstract

In [2] it has been proved that a linear Hamiltonian lattice field perturbed by a conservative stochastic noise belongs to the 3/2-L\'evy/Diffusive universality class in the nonlinear fluctuating theory terminology [15], i.e. energy superdiffuses like an asymmetric stable 3/2-L\'evy process and volume like a Brownian motion. According to this theory this should remain valid at zero tension if the harmonic potential is replaced by an even potential. In this work we consider a quartic anharmonicity and show that the result obtained in the harmonic case persists up to some small critical value of the anharmonicity.

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Cédric Bernardin, Patricia Gonçalves, Milton Jara, Marielle Simon. 2017-03-20. Nonlinear Perturbation of a Noisy Hamiltonian Lattice Field Model: Universality Persistence. https://doi.org/10.1007/s00220-018-3191-z

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