F-theory Description of 3-String Junction

TL;DR

This paper presents a geometric F-theory framework for describing BPS 3-string junctions by lifting IIB string junctions into F-theory and constructing holomorphic curves in K3, unifying strings and junctions.

Contribution

It introduces a novel F-theory geometric approach to describe string junctions, offering advantages over M-theory descriptions.

Findings

Holomorphic curves in K3 represent string junctions.

F-theory provides a unified description of strings and junctions.

The approach simplifies understanding of BPS 3-string junctions.

Abstract

The geometrical description of BPS 3-string junction in the F-theory background is given by lifting a string junction in IIB into F-theory and constructing a holomorphic curve in K3 with respect to a special complex structure of K3. The holomorphic curve is fibration of 1-cycles of the elliptic fiber over the geodesic string junction. The F-theory picture in this paper provides an unifying description of both string and string junction, and is advantageous over the M-theory picture of them.