The question of whether there is no such thing as quantum gravity is a matter of ongoing debate and exploration in theoretical physics. Quantum gravity seeks to reconcile the principles of quantum mechanics with the theory of general relativity, which describes gravity in the framework of classical physics. While general relativity has been highly successful in explaining the behavior of gravity on large scales, it becomes incompatible with quantum mechanics when applied to very small scales, such as those found near black holes or during the early moments of the universe.
It is important to note that despite significant progress, a complete and fully satisfactory theory of quantum gravity has not been established to date. However, it is widely believed among physicists that the reconciliation of quantum mechanics and general relativity is necessary for a comprehensive understanding of fundamental physics.
Several approaches have been proposed to tackle the challenge of quantum gravity, such as string theory, loop quantum gravity, and causal dynamical triangulation, among others. These frameworks attempt to describe the nature of gravity at the quantum level and offer potential paths towards resolving the incompatibilities between quantum mechanics and general relativity.
While the search for a theory of quantum gravity continues, it is also conceivable that our current understanding of gravity and its quantum behavior may need to be revised or expanded. Some physicists have put forth alternative ideas, such as emergent gravity or modified gravity theories, which seek to explain gravity without invoking a fully quantized gravitational field.
In summary, the existence of a theory of quantum gravity is still an open question in theoretical physics. The majority of physicists expect that a consistent theory of quantum gravity will eventually be found, but the specific details and formulation of such a theory are yet to be determined.