Hypercharge Flux, Exotics, and Anomaly Cancellation in F-theory GUTs

TL;DR

This paper clarifies how hypercharge flux constraints in F-theory GUTs with U(1) symmetries are derived from 4D anomaly cancellation, providing a physical basis for previously observed restrictions across different formalisms.

Contribution

It establishes that hypercharge flux restrictions stem from anomaly cancellation, unifying phenomenological constraints regardless of the modeling approach.

Findings

Hypercharge flux constraints follow from anomaly cancellation.

Restrictions are independent of the spectral cover formalism.

Implications for F-theory GUT model building are clarified.

Abstract

We sharpen constraints related to hypercharge flux in F-theory GUTs that possess U(1) symmetries and argue that they arise as a consequence of 4-dimensional anomaly cancellation. This gives a physical explanation for all restrictions that were observed in spectral cover models while demonstrating that the phenomenological implications for a well-motivated set of models are not tied to any particular formalism.