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arXiv · 2105.05251

Quantum Fisher Cosmology: Confronting Observations and the Trans-Planckian Problem

Abstract

The aim of Quantum Fisher Cosmology is to use the quantum Fisher information about pure de Sitter states to derive model independent observational consequences of the existence of a primordial phase of the Universe of de Sitter accelerated expansion. These quantum features are encoded in a scale dependent quantum cosmological tilt that defines what we can call the de Sitter universality class. The experimental predictions are: i) A phase transition from red into blue tilt at a scale order $k= 1$ Mpc$^{-1}$ that naturally solves the cosmological trans-Planckian problem, ii) A spectral index for curvature fluctuations at CMB scales $k= 0.05$ Mpc$^{-1}$ equal to $0.0328$, iii) A tilt running at scale $k=0.002$ Mpc$^{-1}$ equal to $-0.0019$, iv) An enhancement of the amplitude of CMB peaks for extremely high multipoles ($l > 10^5$) that can provide a natural mechanism for primordial black hole formation as a source of dark matter, v) A lack of power at scales of $8$ Mpc with respect to the CMB scale that can explain the $\sigma_8$ tension.

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Cesar Gomez, Raul Jimenez. 2021-05-11. Quantum Fisher Cosmology: Confronting Observations and the Trans-Planckian Problem. https://doi.org/10.1088/1475-7516%2F2021%2F09%2F016

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