ИСТИНА

Initially, a knot is defined as an embedding of the circle into the three-dimensional space considered up to isotopies. But it is often convenient to look at them more combinatorially. From a combinatorial point of view, knots are determined by graphs of special type (called knot diagrams, they can be thought of as projections of knots on a plane), which can be turned into each other by series of special transformations (called Reidemeister moves). In the talk we concern the question what hidden information can be contained in a knot diagram (namely, in the vertices of the diagram), and the theory of parity originated by this question.