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arXiv · 1310.7592

Decelerating cosmologies are de-scramblers

Daniel Carney·Willy Fischler
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Abstract

Stationary observers in static spacetimes see falling objects spread exponentially fast, or fast-scramble, near event horizons. We generalize this picture to arbitrary cosmological horizons. We give examples of exponential fast-scrambling and power-law scrambling and "de-scrambling" as charges propagate freely near a horizon. In particular we show that when the universe is decelerating, information hidden behind the apparent horizon is de-scrambled as it re-enters the view of the observer. In contrast to the de Sitter case, the power-law scaling suggests that the microscopic dynamics of the horizon are local.

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Daniel Carney, Willy Fischler. 2013-10-28. Decelerating cosmologies are de-scramblers. https://doi.org/10.1007/jhep08(2015)043

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