Relative A1\mathbb{A}^1-Contractibility of Smooth Schemes and Exotic Motivic Spheres

This thesis extends the relative A1\mathbb{A}^1-contractibility of Koras-Russell threefolds and their higher-dimensional prototypes to arbitrary Noetherian base schemes, thereby establishing the existence of the first known family of smooth "exotic" motivic spheres in dimensions n4n \geq 4 that are A1\mathbb{A}^1-homotopic to, but not isomorphic to, the punctured affine space An{0}\mathbb{A}^n \setminus \{0\}.

Krishna Kumar Madhavan Vijayalakshmi2026-03-05🔢 math

Index and Robustness of Mixed Equilibria: An Algebraic Approach

This paper introduces an algebraic method, based on Eisenbud et al. (1977), for computing the index of completely mixed equilibria in finite games to demonstrate that any integer can be such an index, while showing that for monogenic equilibria the index is restricted to {1,0,1}\{-1, 0, 1\} with non-zero values equivalent to payoff-robustness, and further extends these findings to extensive-form and boundary equilibria.

Lucas Pahl2026-03-05🔢 math

Classification and Birational Equivalence of Dimer Integrable Systems for Reflexive Polygons

This paper presents a complete classification of dimer integrable systems associated with the 16 reflexive polygons, detailing their Hamiltonian structures and spectral curves while identifying 16 birational equivalences that group them into five distinct classes and demonstrate how brane tiling deformations preserve key moduli space invariants.

Minsung Kho, Norton Lee, Rak-Kyeong Seong2026-03-02⚛️ hep-th