  The strong version of Maldacena's AdS/CFT conjecture implies that the large N
expansion of free N=4 super-YM theory describes an interacting string theory in
the extreme limit of high spacetime curvature relative to the string length.
String states may then be understood as composed of SYM string bits. We
investigate part of the low-lying spectrum of the tensionless (zero-coupling)
limit and find a large number of states that are not present in the infinite
tension (strong-coupling) limit, notably several massless spin two particles.
We observe that all conformal dimensions are N-independent in the free SYM
theory, implying that masses in the corresponding string theory are unchanged
by string interactions. Degenerate string states do however mix in the
interacting string theory because of the complicated N-dependence of general
CFT two-point functions. Finally we verify the CFT crossing symmetry, which
corresponds to the dual properties of string scattering amplitudes. This means
that the SYM operator correlation functions define AdS dual models analogous to
the Minkowski dual models that gave rise to string theory.
