Nambu-Goto Equation from Three-dimensional Gravity

Defects (interfaces) are important probes in quantum field
theories and are also ubiquitous in condensed matter systems. In the
holographic study of such interfaces in two-dimensional conformal field
theories using a thin-brane model, we encountered a surprising
correspondence between the solutions of three-dimensional gravity,
obtained by gluing two identical copies of a spacetime across a tensile
string and the solutions of the Nambu-Goto equation in the same spacetime.
In this talk, I will demonstrate how the non-linear Nambu-Goto equation
(along with other corrections ) emerges directly from the Israel gluing
conditions, somewhat implying that the classical motion of the fundamental
string is itself a consequence of spacetime dynamics in three dimensions.
From a gravitational perspective, our results are valid both in
three-dimensional flat and AdS space. In the latter context  (AdS3_3/CFT_2
correspondence), our setup could be used to describe a noble class of
dynamical interfaces that encodes the Nambu-Goto dynamics of the bulk
junction. Finally, I will conclude with multiple interesting future
directions emerging from our work.