Abstract: Let G be a
finite graph. The Jacobian torus of G
is defined as the torus Let H
be a regular covering of G with an
abelian covering transformation group A.
The surjective homomorphism associated with the covering map gives an injective homomorphism of
the torus into We show that the volume of the
subtorus associated with the middle graph of H
is expressed by the data
of G.
Keywords and phrases: abelian covering graph, line graph, Jacobian torus.
