$T\bar{T}$ deformed soft theorem

In this paper, we derive a $T\bar{T}$ deformed soft graviton theorem in the context of celestial holography. As a concrete example, it illustrates that a two-dimensional irrelevant deformation can be applied to a four-dimensional theory at the level of amplitudes. We argue that the $T\bar{T}$ deformation has a close relation to the loop-correction from the amplitude side which could provide an alternative way to construct an ultraviolet complete quantum theory of gravity.