Imports
/- Copyright (c) 2025 Joseph Tooby-Smith. All rights reserved. Released under Apache 2.0 license as described in the file LICENSE. Authors: Joseph Tooby-Smith -/ module public import Physlib.Meta.TODO.Basic public import Mathlib.Data.Fintype.Sets

Allowed charges

i. Overview

Within SU(5) F-theory with 10d and 5-bar matter fields there are constraints on the allowed U(1) charges the fields can have. These constraints are determined in arXiv:1504.05593. They are related to the distinct configurations of the zero-section (σ₀) relativity to the additional rational section (σ₁s) in codimension one fiber. For our purposes here, we currently just state the constraints found in arXiv:1504.05593, and leave the proof and derivation of these constraints to future work.

ii. Key results

    CodimensionOneConfig : The distinct configurations of the zero-section (σ₀) relativity to the additional rational section (σ₁s) in the codimension one fiber, I₅.

    CodimensionOneConfig.allowedBarFiveCharges : The allowed U(1)-charges of matter in the 5-bar representation of SU(5) given a CodimensionOneConfig.

    CodimensionOneConfig.allowedTenCharges : The allowed U(1)-charges of matter in the 10d representation of SU(5) given a CodimensionOneConfig.

iii. Table of contents

    A. The distinct section configurations

      A.1. The finiteness of the set of configurations

    B. The allowed charges given a configuration

      B.1. The allowed charges of the 5-bar matter

      B.2. The allowed charges of the 10d matter

      B.3. The finiteness of the allowed charges

iv. References

The main reference for the material in this section is the paper:

Lawrie, Schafer-Nameki and Wong. F-theory and All Things Rational: Surveying U(1) Symmetries with Rational Sections https://arxiv.org/pdf/1504.05593. Page 6.

    See also footnote 4 of 1507.05961

@[expose] public sectionTODO "The results in this file are currently stated, but not proved. They should should be proved following e.g. https://arxiv.org/pdf/1504.05593. This is a large project."

A. The distinct section configurations

The distinct codimension one configurations of the zero-section (σ₀) relativity to the additional rational section (σ₁s).

σ₀ and σ₁ intersect the same ℙ¹ of the I₅ Kodaira fiber. This is sometimes denoted I₅^{(01)}

σ₀ and σ₁ intersect the nearest neighbor ℙ¹s of the I₅ Kodaira fiber. This is sometimes denoted I₅^{(0|1)}

σ₀ and σ₁ intersect the next to nearest neighbor ℙ¹s of the I₅ Kodaira fiber. This is sometimes denoted I₅^{(0||1)}

inductive CodimensionOneConfig | same : CodimensionOneConfig | nearestNeighbor : CodimensionOneConfig | nextToNearestNeighbor : CodimensionOneConfig deriving DecidableEq

A.1. The finiteness of the set of configurations

instance : Fintype CodimensionOneConfig where elems := {same, nearestNeighbor, nextToNearestNeighbor} complete := (x : CodimensionOneConfig), x {same, nearestNeighbor, nextToNearestNeighbor} same {same, nearestNeighbor, nextToNearestNeighbor}nearestNeighbor {same, nearestNeighbor, nextToNearestNeighbor}nextToNearestNeighbor {same, nearestNeighbor, nextToNearestNeighbor} same {same, nearestNeighbor, nextToNearestNeighbor}nearestNeighbor {same, nearestNeighbor, nextToNearestNeighbor}nextToNearestNeighbor {same, nearestNeighbor, nextToNearestNeighbor} All goals completed! 🐙

B. The allowed charges given a configuration

B.1. The allowed charges of the 5-bar matter

The allowed U(1)-charges of matter in the 5-bar representation of SU(5) given a CodimensionOneConfig.

def allowedBarFiveCharges : CodimensionOneConfig Finset | same => {-3, -2, -1, 0, 1, 2, 3} | nearestNeighbor => {-14, -9, -4, 1, 6, 11} | nextToNearestNeighbor => {-13, -8, -3, 2, 7, 12}

B.2. The allowed charges of the 10d matter

The allowed U(1)-charges of matter in the 10d representation of SU(5) given a CodimensionOneConfig.

def allowedTenCharges : CodimensionOneConfig Finset | same => {-3, -2, -1, 0, 1, 2, 3} | nearestNeighbor => {-12, -7, -2, 3, 8, 13} | nextToNearestNeighbor => {-9, -4, 1, 6, 11}

B.3. The finiteness of the allowed charges

instance : (I : CodimensionOneConfig) Fintype I.allowedBarFiveCharges | same => inferInstance | nearestNeighbor => inferInstance | nextToNearestNeighbor => inferInstanceinstance : (I : CodimensionOneConfig) Fintype I.allowedTenCharges | same => inferInstance | nearestNeighbor => inferInstance | nextToNearestNeighbor => inferInstance