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There exist consistent temporal logics admitting changes of History

Gavriel Segre
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Abstract

Introducing his Chronology Protection Conjecture Stephen Hawking said that it seems that there exists a Chronology Protection Agency making the Universe safe for historians. Without taking sides about such a conjecture we show that the Chronology Protection Agency is not necessary in order to make the Universe unsafe for historians but safe for logicians.

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Gavriel Segre. 2006-12-05. There exist consistent temporal logics admitting changes of History. https://arxiv.org/abs/gr-qc/0612021

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