Dynamics of Inspiraling Dark Energy

Understand

We investigate the dynamics of a multifield dark energy model, which arises from certain rapid-turning and inspiraling trajectories in field space.

• We find the speed of sound $c_s$ of the dark energy perturbations around the background and show that $c_s$ is monotonically decreasing with time.
• Furthermore, it has a positive-definite lower bound that implies a certain clustering scale.
• We also extend the previously known background solution for dark energy to an exact solution that includes matter.