🔢 mathematics

A Novel Compartmental Model for the Mathematical Epidemiology of Addiction: Backward Bifurcation, Bistability, Persistence, and Treatment-Capacity Policy Implications

This paper develops a novel four-compartment epidemiological model for addiction dynamics that demonstrates how treatment-capacity saturation, rather than incidence saturation, uniquely drives backward bifurcation and bistability, creating a critical policy gap where the basic reproduction number fails to capture the risk of long-term persistence even below traditional thresholds.

Milad tahavor, Reza Memarbashi, Khashayar Ashkboos, Mohammad Mehdipour Zarrinkamar2026-08-25
🔢 mathematics

On holomorphic retracts of polyballs with strictly convex factors and applications

This paper characterizes holomorphic retracts through the center of polyballs with strictly convex factors as either biholomorphic to linear retracts of individual factors or products thereof, a result that establishes the essential uniqueness of their product representations by proving they cannot be biholomorphically equivalent to other product domains with differing factor counts or dimensions.

Balakumar G. P., Jiju Mammen2026-08-24
🔢 mathematics

A Complementary Assignment Method for Delaying Group-Stage Rematches in the FIFA World Cup 2026 Knockout Bracket

This paper proposes a modified assignment method for the FIFA World Cup 2026 knockout bracket that treats the allocation of third-place qualifiers as a capacitated bipartite matching problem to ensure that no two teams from the same group meet before the semi-finals, thereby improving fairness and tournament appeal compared to the official schedule which fails this condition in 70 out of 495 scenarios.

Badr Boutaleb Joutei, Mourad Raif2026-08-24
🔢 mathematics

When Are AI Explanations Recoverable? Identifiability, Stability, and Transfer from an Inverse-Problem Perspective

This paper establishes a mathematical framework for determining the recoverability of AI explanations by formulating them as inverse problems, deriving a complete trichotomy of identifiability and stability conditions for linear and nonlinear systems, and providing explicit bounds that distinguish intrinsic underdetermination from algorithmic variability.

Chibuike Chiedozie Ibebuchi2026-08-24
🔢 mathematics

Regularization and Stability-Bifurcation-Chaos Trilogy for Caputo Fractional Replicator Dynamics with Global Lipschitz Guarantees

This paper introduces a regularized three-dimensional Caputo fractional replicator system with emotional factors that resolves the inherent singularity at the origin, establishes global Lipschitz continuity, and analytically characterizes the complete dynamical transition from stability to chaos through Hopf bifurcation and chaos certification, all validated against unregularized models and empirical behavioral data.

Tongxing Li, Yongfeng Zhang, Xiaodong Zhao, Jianzhong Zhang, Chengdai Huang2026-08-23