New type of saddle in the Euclidean IKKT matrix model and its emergent geometry
Henry Liao, Reishi Maeta · Physical review. D/Physical review. D. · 2026
We study the equation of motion of the Euclidean Ishibashi-Kawai-Kitazawa-Tsuchiya matrix model, and realize a new type of classical saddle that only exists in the N → ∞ limit. Under the assumption that the matrices are the generators of so ( n , m ) , we identify a unique solution, that is, so ( 1 , 3 ) . Even though it has 6 generators and thus 6 nonzero matrices, they are not independent due to the 2 Casimir constraints in so ( 1 , 3 ) . Exploiting the Lie-algebraic structure and the Casimir constraints, we derive a four-dimensional space that a test scalar propagates on. The associated metric possesses SU(2) isometry, which is closely related to the Taub–Newman-Unti-Tamburino/Bolt geometry and may, more broadly, be related to black hole physics.