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arXiv · 2405.10692

STOLAS: STOchastic LAttice Simulation of cosmic inflation

Yurino Mizuguchi·Tomoaki Murata·Yuichiro Tada
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Abstract

We develop a C++ package of the STOchastic LAttice Simulation (STOLAS) of cosmic inflation. It performs the numerical lattice simulation in the application of the stochastic-$\delta N$ formalism. STOLAS can directly compute the three-dimensional map of the observable curvature perturbation without estimating its statistical properties. In its application to two toy models of inflation, chaotic inflation and Starobinsky's linear-potential inflation, we confirm that STOLAS is well-consistent with the standard perturbation theory. Furthermore, by introducing the importance sampling technique, we have success in numerically sampling the current abundance of primordial black holes in a non-perturbative way. The package is available at https://github.com/STOchasticLAtticeSimulation/STOLAS_dist.

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Yurino Mizuguchi, Tomoaki Murata, Yuichiro Tada. 2024-05-17. STOLAS: STOchastic LAttice Simulation of cosmic inflation. https://doi.org/10.1088/1475-7516%2F2024%2F12%2F050

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