  We consider a field theory with target space being the two dimensional sphere
S^2 and defined on the space-time S^3 x R. The Lagrangean is the square of the
pull-back of the area form on S^2. It is invariant under the conformal group
SO(4,2) and the infinite dimensional group of area preserving diffeomorphisms
of S^2. We construct an infinite number of exact soliton solutions with
non-trivial Hopf topological charges. The solutions spin with a frequency which
is bounded above by a quantity proportional to the inverse of the radius of
S^3. The construction of the solutions is made possible by an ansatz which
explores the conformal symmetry and a U(1) subgroup of the area preserving
diffeomorphism group.
