The Vlasov-Poisson and Vlasov-Einstein systems model the motion of a self g
ravitating system such as a galaxy. The Vlasov-Poisson system is nonrelativ
istic. Jeans' theorem states that every spherically symmetric solution of t
he Vlasov-Poisson system that is independent of time may be expressed as a
function of the two invariants, energy and angular momentum, This paper sho
ws this is not the case for the Vlasov-Einstein system.