# Stable equilibrium point and oscillatory motion of the Universe in a model with variable vacuum energy

## TL;DR

This paper proposes a model where variable vacuum energy, influenced by strong self-interactions, leads to a stable equilibrium and oscillatory behavior of the universe's scale factor, offering insights into cosmological dynamics.

## Contribution

It introduces a non-perturbative approach to model variable vacuum energy through quasi-particles, linking strong interactions to cosmological oscillations.

## Key findings

- Predicts oscillatory universe behavior
- Identifies a stable equilibrium point in cosmic evolution
- Links scalar field interactions to cosmological acceleration

## Abstract

We discuss the mechanism by which the field vacuum energy varies as a result of strong self-interaction. We propose a non-perturbative approach to treat strong interactions and discuss the problem in terms of quasi-particles describing the motion of field modes. The resulting vacuum energy is variable and depends on the state of the system. If the interacting scalar field is related to the cosmological field, an acceleration equation with a stable equilibrium point follows in a simple model, predicting the oscillatory behavior of the scale factor and other cosmological effects.