Quantum field theory (QFT) and string theory are two different frameworks used to describe fundamental particles and their interactions. While QFT focuses on point-like particles and fields, string theory introduces one-dimensional objects called strings as the fundamental building blocks of the universe.
However, there is a relationship between quantum field theory and string theory that provides a way to interpret QFT within the framework of string theory. This relationship is known as the AdS/CFT correspondence or gauge/gravity duality.
The AdS/CFT correspondence states that certain quantum field theories in a particular number of dimensions are mathematically equivalent to string theories in a higher-dimensional anti-de Sitter (AdS) spacetime. This duality suggests that the physics of the quantum field theory is dual to the physics of string theory in a curved spacetime.
In this interpretation, the quantum field theory living on the boundary of the AdS spacetime is mapped to the string theory living in the bulk of the higher-dimensional spacetime. The field theory describes the behavior of certain particles and interactions, while the string theory provides a geometric description of the bulk spacetime and its dynamics.
This duality has been particularly useful in studying strongly interacting field theories, where traditional techniques of QFT calculations are challenging. By mapping the field theory to a dual string theory, physicists can gain insights into the properties and behavior of the field theory by studying the corresponding string theory.
The AdS/CFT correspondence has provided many important insights into the study of quantum field theory, including aspects related to quantum gravity, black holes, and the dynamics of strongly coupled systems. It has deepened our understanding of the interplay between quantum field theory and string theory, bridging the gap between these two frameworks and providing new perspectives on the nature of fundamental particles and their interactions.