TITLE:
Physical Properties of the Types of Dark Energy Introduced in Light of the “DESI-Pressure” upon the ΛCDM Universe Model
AUTHORS:
Øyvind G. Grøn
KEYWORDS:
Dark Energy, Cosmological Model, Equation of State, Hubble Tension, Deceleration Parameter
JOURNAL NAME:
Journal of Applied Mathematics and Physics,
Vol.14 No.2,
February
28,
2026
ABSTRACT: This paper presents an introduction to the main point in the changes of the ΛCDM-universe model that the cosmologists have proposed in light of the DESI-observational data and other types of observations: New types of dark energy characterized by different equations of state than that of Lorentz invariant vacuum energy, LIVE, with constant density in the ΛCDM-universe model. Gravitational properties and time evolution of these new types of dark energy are discussed and illustrated graphically by employing analytical expressions for dimensionless density factors, resulting from integrating the equation of continuity of the different models. The density factors are employed to calculate the time evolution of the deceleration parameters of universe models with different types of dark energy. It is also shown that the introduction of the w0waCDM-universe models changes the value of Hubble’s constant relative to that of the ΛCDM-universe model, but with a too small magnitude to solve the Hubble tension. It is argued that this is a general feature of all dynamical dark energy models constrained by low redshift data.