The nature of quantum gravity, which seeks to describe the behavior of gravity at the quantum level, is still an area of active research and remains a topic of significant theoretical investigation. While several approaches to quantum gravity exist, such as string theory, loop quantum gravity, and causal dynamical triangulations, a complete and experimentally confirmed theory of quantum gravity is yet to be established.
In these theories, including string theory, there are proposals that suggest the existence of additional internal dimensions beyond the three spatial dimensions we are familiar with. These extra dimensions are typically considered to be compactified or "curled up" at incredibly small scales, often referred to as a "quantum space." These internal dimensions would play a role in the quantum description of gravity and may influence the behavior of gravitational interactions on small scales.
However, it's important to note that the existence and properties of these internal dimensions are purely speculative at this point, as experimental evidence or direct observations supporting their existence are currently lacking. The search for experimental or observational signatures of quantum gravity effects, including the presence of extra dimensions, remains an active field of research, but conclusive evidence has not yet been obtained.
It is also worth mentioning that the exact nature of how quantum gravity may manifest in terms of internal dimensions, if they exist, is highly uncertain and is an ongoing topic of investigation. Various theoretical frameworks propose different ideas about the structure of these dimensions and their influence on the behavior of gravity and other fundamental forces.
In summary, while the concept of internal dimensions or a quantum space is explored in some theories of quantum gravity, the definitive understanding and experimental verification of such concepts are yet to be achieved. The investigation of quantum gravity and its potential implications for our understanding of spacetime and fundamental interactions is an active and exciting area of research in theoretical physics.