# Holographic Bulk Reconstruction And Cosmological Singularities

## TL;DR

This paper explores how entanglement wedge reconstruction in a Kasner-AdS cosmological model reveals the limitations of causal methods and demonstrates the superiority of modular reconstruction in the presence of singularities.

## Contribution

It shows that modular reconstruction outperforms causal reconstruction in AdS/CFT models with cosmological singularities, highlighting the importance of operator subalgebras.

## Key findings

- Modular reconstruction is more effective than causal methods near singularities.
- Causal reconstruction is limited by the presence of cosmological singularities.
- Modular methods leverage operator subalgebras for better bulk reconstruction.

## Abstract

We study the structure of entanglement wedges in the Kasner-AdS geometry, which provides an example of AdS/CFT engineered cosmological singularity. We investigate the specific limitations of causal reconstruction methods, imposed by the presence of the cosmological singularities, and we show the supremacy of modular reconstruction. This model provides an example where modular reconstruction based on a proper operator subalgebra is more powerful than the strongest possible causal reconstruction, based on the complete operator algebra.