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arXiv · 1012.2393

Past and future blurring at fundamental length scale

M. J. Neves·C. Farina·M. V. Cougo-Pinto
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Abstract

We obtain the $κ$-deformed versions of the retarded and advanced Green functions and show that their causality properties are blurred in a time interval of the order of a length parameter $q=1/(2κ)$. The functions also indicate a smearing of the light cone. These results favor the interpretation of $q$ as a fundamental length scale below which the concept of a point in spacetime should be substituted by the concept of a fuzzy region of radius $q$, as proposed long ago by Heisenberg.

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M. J. Neves, C. Farina, M. V. Cougo-Pinto. 2010-12-10. Past and future blurring at fundamental length scale. https://doi.org/10.1103/physrevlett.105.211601

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