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arXiv · 1812.02345

Towards a Fisher-information description of complexity in de Sitter universe

Chong-Bin Chen·Fu-Wen Shu
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Abstract

Recent developments on holography and quantum information physics suggest that quantum information theory come to play a fundamental role in understanding quantum gravity. Cosmology, on the other hand, plays a significant role in testing quantum gravity effects. How to apply this idea to a realistic universe is still missing. Here we show some concepts in quantum information theory have their cosmological descriptions. Particularly, we show complexity of a tensor network can be regarded as a Fisher information measure(FIM) of a dS universe, followed by several observations: (i) the holographic entanglement entropy has a tensor-network description and admits a information-theoretical interpretation, (ii) on-shell action of dS spacetime has a same description of FIM, (iii) complexity/action(CA) duality holds for dS spacetime. Our result is also valid for $f(R)$ gravity, whose FIM exhibits the same features of a recent proposed $L^n$ norm complexity.

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Chong-Bin Chen, Fu-Wen Shu. 2018-12-06. Towards a Fisher-information description of complexity in de Sitter universe. https://doi.org/10.3390/universe5120221

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