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The Breakthrough Prize in Fundamental Physics was awarded to Maldacena for his groundbreaking work on the AdS/CFT correspondence, a remarkable theory that establishes a deep connection between two seemingly disparate theories of physics: the anti-de Sitter (AdS) theory of gravity and the conformal field theory (CFT). This correspondence has revolutionized our understanding of quantum gravity and has opened up new avenues for exploring the fundamental nature of the universe.