  In this paper we consider adversarial noise models that will fail quantum
error correction and fault-tolerant quantum computation.
  We describe known results regarding high-rate noise, sequential computation,
and reversible noisy computation. We continue by discussing highly correlated
noise and the "boundary," in terms of correlation of errors, of the "threshold
theorem." Next, we draw a picture of adversarial forms of noise called
(collectively) "detrimental noise."
  Detrimental noise is modeled after familiar properties of noise propagation.
However, it can have various causes. We start by pointing out the difference
between detrimental noise and standard noise models for two qubits and proceed
to a discussion of highly entangled states, the rate of noise, and general
noisy quantum systems.
