  We propose two different high-energy-theory correspondences with graphene
(and related materials) scenarios, associated to grain boundaries, that are
topological defects for which both Dirac points are necessary. The first
correspondence points to a $(3+1)$-dimensional theory, with nonzero torsion,
with spatiotemporal gauge group $SO(3,1)$, locally isomorphic to the Lorentz
group in $(3+1)$ dimensions, or to the de Sitter group in $(2+1)$ dimensions.
The other correspondence treats the two Dirac fields as an internal symmetry
doublet, and it is linked here with unconventional supersymmetry with $SU(2)$
internal symmetry. Our results are suggestive, rather than conclusive, and pave
the way to the inclusion of grain boundaries in the emergent field theory
picture associated with these materials, whereas disclinations and dislocations
have been already well explored.
