Random Walk in the Boundary and Slow Roll in the Bulk

Yoshihisa Kitazawa

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arXiv · 2303.07676

Random Walk in the Boundary and Slow Roll in the Bulk

Yoshihisa Kitazawa

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Abstract

The slow rolling inflation is dual to the random walk of conformal zero-mode. The 2 dimensional Fokker-Planck theory predicts the slow roll parameters of 4d inflation theory. The O(N) enhancements of the two point functions, N is the e-folding number, suppress the slow roll parameters by the same magnitude. Under the gaussian approximation, FP equation boils down to a solvable first order partial differential equation. The identical equation is derived by the thermodynamic arguments . We study two types of the solutions of :(1) UV complete spacetime and (2) inflationary spacetime with power potentials. The concavity of entangled entropy dictates the potential of inflation is also concave. The maximum entropy principle favours the scenario: the universe is (a) born small and (b) grows large by inflation in the concave potentials. We predict 1-ns > 0.02(0.016) and r < 0.08(0.066) for N = 50(60)at the pivot angle 0.002(Mpc)-1. we propose a scenario to produce the curvature perturbation in the right ball park.

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Yoshihisa Kitazawa. 2023-03-14. Random Walk in the Boundary and Slow Roll in the Bulk. https://arxiv.org/abs/2303.07676

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