Thomas Wanner
Department of Mathematical Sciences
George Mason University
4400 University Drive, MS 3F2
Fairfax, Virginia 22030, USA

 

Maximum norms of random sums and transient pattern formation

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  1. Thomas Wanner:
    Maximum norms of random sums and transient pattern formation
    Transactions of the American Mathematical Society 356(6), pp. 2251-2279, 2004.

Abstract

Many interesting and complicated patterns in the applied sciences are formed through transient pattern formation processes. In this paper we concentrate on the phenomenon of spinodal decomposition in metal alloys as described by the Cahn-Hilliard equation. This model depends on a small parameter, and one is generally interested in establishing sharp lower bounds on the amplitudes of the patterns as the parameter approaches zero. Recent results on spinodal decomposition have produced such lower bounds. Unfortunately, for higher-dimensional base domains these bounds are orders of magnitude smaller than what one would expect from simulations and experiments. The bounds exhibit a dependence on the dimension of the domain, which from a theoretical point of view seemed unavoidable, but which could not be observed in practice. In this paper we resolve this apparent paradox. By employing probabilistic methods, we can improve the lower bounds for certain domains and remove the dimension dependence. We thereby obtain optimal results which close the gap between analytical methods and numerical observations, and provide more insight into the nature of the decomposition process. We also indicate how our results can be adapted to other situations.

The published version of the paper can be found at https://doi.org/10.1090/S0002-9947-03-03480-9, see also http://www.jstor.org/stable/3844947.

Bibtex

@article{wanner:04a,
   author = {Thomas Wanner},
   title = {Maximum norms of random sums and transient pattern formation},
   journal = {Transactions of the American Mathematical Society},
   year = 2004,
   volume = 356,
   number = 6,
   pages = {2251--2279},
   doi = {10.1090/S0002-9947-03-03480-9},
   url = {http://www.jstor.org/stable/3844947}
   }