Stochastic Flips on Two-letter Words
نویسندگان
چکیده
This paper introduces a simple Markov process inspired by the problem of quasicrystal growth. It acts over two-letter words by randomly performing flips, a local transformation which exchanges two consecutive different letters. More precisely, only the flips which do not increase the number of pairs of consecutive identical letters are allowed. Fixed-points of such a process thus perfectly alternate different letters. We show that the expected number of flips to converge towards a fixedpoint is bounded by O(n) in the worst-case and by O(n lnn) in the average-case, where n denotes the length of the initial word.
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