The set RT(M) of values of the
SL(2,C)-Reidemeister torsion of a 3-manifold M can be
both finite and infinite. We prove that RT(M) is a finite set if M
is the splice of two certain knots in the 3-sphere. The proof is based on an
observation on the character varieties and A-polynomials of knots.Comment: 16 pages, 1 figure, to appear in Ann. Math. Blaise Pasca