# Scalar modes and the linearized Schwarzschild solution on a quantized FLRW space-time in Yang-Mills matrix models

## TL;DR

This paper investigates scalar perturbations in a quantum FLRW spacetime derived from Yang-Mills matrix models, revealing emergent gravity features and potential dark matter implications.

## Contribution

It demonstrates the emergence of linearized Schwarzschild solutions and long-wavelength scalar modes from a quantum matrix model background.

## Key findings

- Linearized Schwarzschild metric arises as a solution.
- A quasi-static massive graviton mode decreases over cosmic time.
- Scalar modes may mimic dark matter effects.

## Abstract

We study scalar perturbations of a recently found 3+1-dimensional FLRW quantum space-time solution in Yang-Mills matrix models. In particular, the linearized Schwarzschild metric is obtained as a solution. It arises from a quasi-static would-be massive graviton mode, and slowly decreases during the cosmic expansion. Along with the propagating graviton modes, this strongly suggests that 3+1 dimensional (quantum) gravity emerges from the IKKT matrix model on this background. For the dynamical scalar modes, non-linear effects must be taken into account. We argue that they lead to non-Ricci-flat metric perturbations with very long wavelengths, which would be perceived as dark matter from the GR point of view.