Observational constraint on Dark Energy from Quantum Uncertainty
  We explore the theoretical possibility that dark energy density is derived
from massless scalar bosons in vacuum and present a physical model for dark
energy. By assuming massless scalar bosons fall into the horizon boundary of
the cosmos with the expansion of the universe, we can deduce the uncertainty in
the relative position of scalar bosons based on the quantum fluctuation of
space-time and the assumption that scalar bosons satisfy P-symmetry under the
parity transformation ${P}\varphi ({r}) = - \varphi ({r})$, which can be used
to estimate scalar bosons and dark energy density. Furthermore, we attempt to
explain the origin of negative pressure from the increasing entropy density of
the Boltzmann system and derive the equation for the state parameter, which is
consistent with the specific equations of state for dark energy. Finally, we
employ the SNIa Pantheon sample and Planck 2018 CMB angular power spectra to
constrain the models and orovide statistical results for the cosmology
parameters.
