Primordial cosmic complexity and effects of reheating

Abstract

We study the effects of the reheating phase on the evolution of complexities for the primordial curvature perturbation using the squeezed formalism. We examine the evolution of the out-of-time correlator, the quantum discord, and circuit complexity, starting from the inflationary epoch to the radiation-dominated epoch with different reheating scenarios. We find that for a mode that reenters the horizon after reheating, the effect of a finite reheating epoch on the characteristic \textit{freeze-in} amplitude of these primordial complexities can only be distinguished up to three different classes depending on whether the equation of state parameter: $(i)$ $w_{\mathrm{re}}=1/3$ $(ii)$ $w_{\mathrm{re}}<1/3$, or, (iii) $w_{\mathrm{re}}>1/3$. For reheating with different EOS within these classes, the final amplitude will be the same -- hence, the detailed signature of reheating with a class on the complexity measures will be lost. Taking the central value of the scalar spectral index ($n_s=0.9649$) from Planck and the equation of state during reheating $w_{\mathrm{re}}=0.25$ as benchmark values, we found that the behavior of the complexities for all modes smaller than $1.27\times 10^{16}\mathrm{Mp}{\mathrm{c}}^{-1}$ can be classified as above. However, for the small-scale modes reentering the horizon during reheating, the signature of EOS on the evolution of these two complexities will be embedded in each of the cases separately.

17 pages, 8 figures; replaced to match published version

References in corpus (25)

• Quantum discord and the power of one qubit
• Quantum Computation as Geometry
• Lyapunov Exponent and Out-of-Time-Ordered Correlator's Growth Rate in a Chaotic System
• Reheating constraints to inflationary models
• Reheating predictions in single field inflation
• How a small quantum bath can thermalize long localized chains
• Inflation and the Scale Dependent Spectral Index: Prospects and Strategies
• Reheating temperature from the CMB
• Brane inflation and the WMAP data: a Bayesian analysis
• CMB constraints on the inflaton couplings and reheating temperature in $\alpha$-attractor inflation
• The Rise of Cosmological Complexity: Saturation of Growth and Chaos
• Cosmological Krylov Complexity
• Discord and Decoherence
• The Quantum Information of Cosmological Correlations
• Quantum recoherence in the early universe
• The Cosmological OTOC: Formulating new cosmological micro-canonical correlation functions for random chaotic fluctuations in Out-of-Equilibrium Quantum Statistical Field Theory
• Enhanced power on small scales and evolution of quantum state of perturbations in single and two field inflationary models
• Comparing quantumness criteria
• Quantum Circuit Complexity of Primordial Perturbations
• Probing the initial state of inflation: analytical structure of cosmological correlators
• Does inflation squeeze cosmological perturbations?
• Circuit Complexity in an interacting quenched Quantum Field Theory
• Squeezing the Axion
• A Flat Space Analogue for the Quantum Origin of Structure
• Four-mode squeezed states in de Sitter space: A study with two field interacting quantum system

Cited by in corpus (2)

• The Early Universe as an Open Quantum System: Complexity and Decoherence
• Probing the self-coherence of primordial quantum fluctuations with complexity