Yes, that's correct. The current scientific consensus suggests that our observable universe is indeed expanding. This expansion is primarily driven by a phenomenon called dark energy, which is a theoretical form of energy that fills space and exerts a negative pressure. Dark energy is thought to be responsible for the accelerated expansion of the universe.
While dark matter also exists and contributes to the overall mass of the universe, it doesn't directly cause the expansion. Dark matter interacts gravitationally and helps to hold galaxies and other structures together, but its influence on the expansion is not significant compared to dark energy.
The concept of the expansion of the universe was first proposed in the early 20th century and was later confirmed by various observations, such as the redshift of light from distant galaxies. The expansion of space itself means that the distances between galaxies are increasing over time, leading to the observable universe expanding. It's important to note that the expansion of the universe refers to the stretching of space itself rather than the movement of objects within space.
However, it's worth mentioning that our knowledge of dark energy and the nature of the universe is still an active area of research. Scientists continue to study and refine our understanding of these concepts, and future discoveries may provide new insights into the nature of space, dark energy, and the expansion of the universe.