Reverse Turing test subject of the test involves reversing the roles of the real and control subjects. When a Turing test is applied to a mixed group of human and computer subjects, the computers are the nominal subjects. However, the humans are judged in exactly the same way, and so their Turing test scores can also be calculated. This is another way of viewing the situation described in the previous section. The term "reverse Turing test" has also been applied to a Turing test (test of humanity) that is administered by a computer. In other words, a computer administers a test to determine
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