In the standard model of cosmology called λCDM, two key elements were introduced to address certain issues in the behavior of galaxies in clusters as predicted by General Relativity. These elements are dark matter and dark energy. λCDM relies on the equations of General Relativity to distribute the total mass and energy of the universe, attributing 4.92% to matter (including only regular matter), 26.8% to dark matter, and 68.3% to dark energy. This allocation is based on observations made by the Planck mission and does not consider bosonic matter, such as the quantum vacuum. However, the precise nature of dark matter and dark energy remains a mystery. λCDM lacks a complete physical theory of gravity since General Relativity provides powerful equations without a concrete definition of spacetime and a static gravitational field.This has led to certain properties, like curvature, viscosity, a dragging reference frame, and gravitational effects, being incorrectly attributed to spacetime itself by materialist substantivalism, a widely accepted philosophical interpretation that complements General Relativity. In contrast, we propose that these properties actually originate from the quantum vacuum, which is the primary form of matter. In our view, the quantum vacuum serves as the source of both dark matter and dark energy. These two components are opposing effects of the quantum vacuum’s interaction with cosmic structures. When the quantum vacuum interacts gravitationally with these structures, it causes spacetime to curve. As the formation of these structures declines, which has been happening for around five billion years, the quantum vacuum remains nearly flat because its self-gravitational interactions are very weak. This flatness leads to the accelerated expansion of the universe.