Quantum field theory (QFT) as it stands is not able to fully incorporate gravity into its framework. Gravity, described by Einstein's general theory of relativity, is a classical theory of spacetime curvature. On the other hand, quantum field theory is a framework for describing the behavior of quantum fields and their interactions.
Attempts to develop a quantum theory of gravity, often referred to as quantum gravity, aim to reconcile general relativity with quantum mechanics. The most well-known approach to quantum gravity is string theory, which extends the notion of particles to include one-dimensional "strings" and incorporates gravity within its framework. String theory provides a consistent quantum mechanical description of gravity at a fundamental level, but it requires extra dimensions beyond the familiar four (three spatial dimensions plus time) and introduces new mathematical concepts.
Other approaches to quantum gravity include loop quantum gravity, causal dynamical triangulations, and various approaches based on the concept of spacetime quantization. These approaches seek to quantize the gravitational field itself and provide a quantum description of spacetime.
However, it is important to note that a complete and experimentally verified theory of quantum gravity is currently lacking. The challenges involved in formulating a consistent and testable theory of quantum gravity are considerable. The extreme conditions of high energies and small distances associated with quantum gravity require new physical insights and mathematical tools that are not yet fully understood.
In summary, while quantum field theory is successful in describing the behavior of other fundamental forces in the framework of quantum mechanics, it does not fully incorporate gravity. Developing a theory that unifies quantum mechanics and gravity remains an active area of research in theoretical physics.