Reverse Turing test Reverse Turing test A reverse Turing test is a Turing test in which the objective or roles between computers and humans have been reversed. Conventionally, the Turing test is conceived as having a human judge and a computer subject which attempts to appear human. Critical to the concept is the parallel situation of a human judge and a human subject, who also attempts to appear human. The intent of the test is for the judge to attempt to distinguish which of these two situations is actually occurring. It is presumed that a human subject will always be judged human, and
Characteristic class Characteristic class In mathematics, a characteristic class is a way of associating to each principal bundle "X" a cohomology class of "X". The cohomology class measures the extent the bundle is "twisted" — and whether it possesses sections. Characteristic classes are global invariants that measure the deviation of a local product structure from a global product structure. They are one of the unifying geometric concepts in algebraic topology, differential geometry, and algebraic geometry. The notion of characteristic class arose in 1935 in the work of Eduard Stiefel and Hassler Whitney about vector fields on manifolds. Let "G" be a topological