How two Pioneering and Monumental Papers or Journal Articles, published during the late 1990s establish the fundamental pillars of holographic duality (which we today call AdS/CFT correspondence or gauge/gravity duality)

Juan Maldacena’s 1997 paper “The Large N Limit of Superconformal Field Theories and Supergravity”
supplied the bold conjectural core of gauge/gravity duality. By analyzing the near-horizon geometry of D3-branes in type IIB string theory, Maldacena argued that string theory on (AdS5​×S5) is exactly equivalent to N = 4 supersymmetric Yang–Mills theory in four dimensions in the large N limit. This proposal unified several earlier hints—large N gauge theory, black brane physics, and holography—into a single concrete statement equating a quantum gravity theory with a non-gravitational conformal field theory. Crucially, it provided matching symmetries, parameters, and limits (weak/strong duality), thereby turning the vague holographic principle into a testable framework and giving string theory its first non-perturbative definition in a controlled setting.

Edward Witten’s 1998 paper “Anti-de Sitter Space and Holography”
then established the precise operational dictionary that made the conjecture usable. Witten formulated how to compute boundary CFT correlation functions from bulk gravitational physics via the now-standard relation between the bulk partition function and the generating functional of the CFT. He clarified the role of boundary conditions in AdS, identified bulk fields with specific CFT operators, and showed how scaling dimensions arise from bulk masses. This fundamentally established a mathematically consistent framework for a non-perturbative ramification of holographic duality in modern string theory and reconciled two previously domains of modern theoretical physics- QFT and quantum gravity.
In effect, Maldacena provided the physical equivalence, while Witten supplied the mathematical machinery that turned the correspondence into a working calculational framework.

Together—both published in the academic peer-reviewed Journal
Advances in Theoretical and Mathematical Physics—these papers created the foundational pillars of modern holography: Maldacena’s conjecture established the existence of the duality, and Witten’s formalism made it precise and computable. Their combined impact was transformative: they redefined quantum gravity in terms of ordinary quantum field theory, opened a non-perturbative window into strongly coupled gauge dynamics, and catalyzed vast developments across string theory, quantum field theory, black hole physics, and modern mathematical physics.