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Countable state shifts and uniqueness of g-measures

Anders Johansson·Anders Öberg·Mark Pollicott
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Abstract

In this paper we present a new approach to studying g-measures which is based upon local absolute continuity. We extend the result in [11] that square summability of variations of g-functions ensures uniqueness of g-measures. The first extension is to the case of countably many symbols. The second extension is to some cases where $g \geq 0$, relaxing the earlier requirement in [11] that inf g>0.

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Anders Johansson, Anders Öberg, Mark Pollicott. 2005-09-05. Countable state shifts and uniqueness of g-measures. https://doi.org/10.1353/ajm.2007.0044

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