Circuit Complexity of Scalar and Tensor Perturbations in Luminal Einstein--Gauss--Bonnet Inflation
Abstract
We investigate the circuit complexity of primordial scalar and tensor perturbations in the luminal branch of Einstein--Gauss--Bonnet inflation. Starting from the quadratic perturbation actions, we construct the two-mode Hamiltonians and derive the evolution equations for the squeezing amplitudes and angles. Although the tensor speed is fixed to unity, the Gauss--Bonnet (GB) coupling remains dynamical through the scalar and tensor pump fields. We track the squeezing dynamics from the subhorizon to the superhorizon regime and evaluate the Nielsen wave-function complexity of the resulting two-mode squeezed states. The GB correction produces a clear separation in the squeezing amplitudes, while the unwrapped squeezing angles remain nearly phase locked. Consequently, the circuit complexity is controlled mainly by the amplitude evolution. A positive coupling enhances the scalar complexity but slightly suppresses the tensor complexity for the benchmarks considered. These opposite trends show that scalar and tensor Gaussian states retain distinct information about the same modified inflationary background even when tensor propagation is luminal.
Related
- Circuit and Krylov complexity of primordial perturbations of modified gravity in inflation
- Circuit complexity of coupled four-mode squeezed states in two-field inflation
- Scalar perturbations in two-scalar-field warm inflation
- Einstein-Gauss-Bonnet quintessential inflation: From super-inflation to emergent warm inflation
- Enabling Polyspectra via Stochastic Realizations of Inverse Decay Curvature Perturbations in Axion Inflation
BibTeX
@misc{li2026circuit,
title = {{Circuit Complexity of Scalar and Tensor Perturbations in Luminal Einstein--Gauss--Bonnet Inflation}},
author = {Tao Li and Hai-Bing Fu and Lei-Hua Liu},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2611.04441},
eprint = {2611.04441},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2611.04441},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Circuit Complexity of Scalar and Tensor Perturbations in Luminal Einstein--Gauss--Bonnet Inflation
AU - Tao Li
AU - Hai-Bing Fu
AU - Lei-Hua Liu
PY - 2026
DA - 2026/11/03
PB - arXiv
DO - 10.48550/arxiv.2611.04441
UR - https://arxiv.org/abs/2611.04441
AB - We investigate the circuit complexity of primordial scalar and tensor perturbations in the luminal branch of Einstein--Gauss--Bonnet inflation. Starting from the quadratic perturbation actions, we construct the two-mode Hamiltonians and derive the evolution equations for the squeezing amplitudes and angles. Although the tensor speed is fixed to unity, the Gauss--Bonnet (GB) coupling remains dynamical through the scalar and tensor pump fields. We track the squeezing dynamics from the subhorizon to the superhorizon regime and evaluate the Nielsen wave-function complexity of the resulting two-mode squeezed states. The GB correction produces a clear separation in the squeezing amplitudes, while the unwrapped squeezing angles remain nearly phase locked. Consequently, the circuit complexity is controlled mainly by the amplitude evolution. A positive coupling enhances the scalar complexity but slightly suppresses the tensor complexity for the benchmarks considered. These opposite trends show that scalar and tensor Gaussian states retain distinct information about the same modified inflationary background even when tensor propagation is luminal.
ER -