Speaker
Description
We investigate the quantum dynamics of a spatially homogeneous quintessence field. It is thought that the ground state of the quintessence acts as the cosmological constant in the dynamical dark energy framework. The correlation function and power spectrum of quantum fluctuations exhibit ultraviolet divergence. To address this issue, we reformulate the system by interpreting quintessence as a lattice of rigidly coupled harmonic oscillators starting from $V(\phi)=m^2\phi^2/2$. Within this context, we apply the Heisenberg-Langevin formalism, incorporating both Hubble-induced damping and Markovian stochastic noise to effectively describe the dissipative quantum dynamics. We derive the corresponding ladder operators and determine the effective energy density. Finally, we generalize this formulation to encompass any arbitrary potential, thereby extending the utility of this framework to a wide range of dynamical dark energy models using quantum mechanics.