From Local to Global in F-Theory Model Building

Understand

When locally engineering F-theory models some D7-branes for the gauge group factors are specified and matter is localized on the intersection curves of the compact parts of the world-volumes.

• In this note we discuss to what extent one can draw conclusions about F-theory models by just restricting the attention locally to a particular seven-brane.
• Globally the possible D7-branes are not independent from each other and the (compact part of the) D7-brane can have unavoidable intrinsic singularities.
• Many special intersecting loci which were not chosen by hand occur inevitably, notably codimension three loci which are not intersections of matter curves.