Stateless depends on the context, it doesn't violate any theory of computing. Here are some elements of stateless systems:

  * all the state needed for serving requests is transient, not something that needs to be persisted
  * any particular instance can disappear without affecting the observable behavior of the system
  * the system is infinitely scalable: it doesn't matter if the cluster is comprised of 1, 100 or 1000 instances