According to our current understanding of physics, gravity is not described by a particle in the same way as other fundamental forces like the electromagnetic force, which is mediated by photons. Instead, gravity is described by the theory of general relativity, formulated by Albert Einstein.
In general relativity, gravity is not attributed to a specific particle but is instead understood as the curvature of spacetime caused by mass and energy. According to this theory, massive objects such as planets, stars, and galaxies curve the fabric of spacetime around them, and other objects moving in that curved spacetime experience the effects of gravity.
However, it's important to note that there are ongoing efforts to reconcile general relativity with quantum mechanics, which describes the behavior of particles at the quantum level. These efforts aim to develop a theory of quantum gravity that would provide a more complete understanding of the nature of gravity, particularly at the smallest scales. Some proposed theories, such as string theory and loop quantum gravity, suggest the existence of particles called gravitons that mediate the gravitational force in a manner similar to how photons mediate the electromagnetic force. However, these theories are still speculative and under active investigation, and experimental evidence for gravitons or a quantum theory of gravity is yet to be discovered.