Stochastic Selection of Cosmological Constant in Chaotic Inflation: A String Theory Landscape Approach

- Planck Collaboration (2018), *Astronomy & Astrophysics* 641, A6.  

- DES Collaboration (2022), *Physical Review D* 105, 083524.  

- LiteBIRD Collaboration (2023), *Journal of Cosmology and Astroparticle Physics* 03, 011.

Refinements and Additional Derivations

A1. Theoretical Improvements

Parameter Dependence and Measure Problem Solutions

The model's predictions depend critically on string theory parameters (e.g.,qiqi,inni, compactification volume VV). Key challenges and alternatives:

• Parameter Sensitivity:

The decay constant ff must be fine-tuned to 0.1MPl0.1MPl to match r0.003 r0.003.

Mitigation: Use statistical distributions of ff from ensemble of Calabi-Yau manifolds (Douglas et al., 2009).

• Measure Problem: