  We consider gauge coupling unification in E6 F-Theory Grand Unified Theories
(GUTs) where E6 is broken to the Standard Model (SM) gauge group using fluxes.
In such models there are two types of exotics that can affect gauge coupling
unification, namely matter exotics from the matter curves in the 27 dimensional
representation of E6 and the bulk exotics from the adjoint 78 dimensional
representation of E6. We explore the conditions required for either the
complete or partial removal of bulk exotics from the low energy spectrum. In
the latter case we shall show that (miraculously) gauge coupling unification
may be possible even if there are bulk exotics at the TeV scale. Indeed in some
cases it is necessary for bulk exotics to survive to the TeV scale in order to
cancel the effects coming from other TeV scale matter exotics which would by
themselves spoil gauge coupling unification. The combination of matter and bulk
exotics in these cases can lead to precise gauge coupling unification which
would not be possible with either type of exotics considered by themselves. The
combination of matter and bulk exotics at the TeV scale represents a unique and
striking signature of E6 F-theory GUTs that can be tested at the LHC.

High Energy Physics - Phenomenology;High Energy Physics - Theory