No, our universe, as we understand it, cannot exist in only one dimension. Our universe is observed to have three spatial dimensions (length, width, and height) and one temporal dimension (time), which together form a four-dimensional spacetime.
One-dimensional systems, often represented as lines, possess only a single spatial dimension. In such a system, objects or entities can only move back and forth along the line. A one-dimensional universe would lack the complexity and richness of the three-dimensional world we experience.
The existence of multiple dimensions beyond the first is supported by numerous scientific observations and theories. For instance, the behavior of objects in our universe, the fundamental forces acting upon them, and the predictions of various physical theories (such as general relativity and quantum mechanics) all point to a multidimensional reality.
Additionally, the concept of a one-dimensional universe raises significant challenges when it comes to explaining phenomena such as the formation of structures, the interactions of particles, the existence of diverse objects, and the emergence of complexity. These aspects of our universe are better understood and described within a framework that incorporates multiple dimensions.
It's worth noting that there are mathematical models and theoretical frameworks, such as string theory, that propose the existence of additional, compactified dimensions beyond the four we experience. However, these extra dimensions are typically not observable or directly perceivable on macroscopic scales, and their effects become significant only at incredibly small scales or in high-energy scenarios.