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arXiv · 2502.09463

Fractional instantons and Confinement: first results on a $T_2\times R^2$ roadmap

Georg Bergner·Antonio González-Arroyo·Ivan Soler
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Abstract

We report results obtained for SU(2) Yang-Mills theory on a four dimensional torus with two directions much smaller than the other two. The small 2-torus is equipped with twisted boundary conditions. This construction provides a way to interpolate from a region in which semiclassical methods can be applied (for small 2-torus size) to the standard infinite volume case. Our simulations at small torus sizes show how the topological charge and the string tension result from a gas of vortex-like fractional instantons. As the size becomes larger the density increases and the separation of structures tends to a constant in agreement with the fractional instanton liquid model picture of the Yang-Mills vacuum.

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Georg Bergner, Antonio González-Arroyo, Ivan Soler. 2025-02-13. Fractional instantons and Confinement: first results on a $T_2\times R^2$ roadmap. https://arxiv.org/abs/2502.09463

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