The problem under consideration is that of determining a simple and effective invariant of knots. To this end, the Conway polynomial is defined as a generalization of Alexander's original knot polynomial. It is noted, however, that the Conway polynomial is not a complete invariant. If two knots are equivalent, as defined in this investigation, then they receive identical polynomials. Yet, if two knots have identical polynomials, no information about their equivalence may be obtained. To define the Conway polynomial, the Axioms for Computation are given and many examples of their use are included. A major result of this investigation is the proof of topological invariance of these polynomials and the proof that the axioms are sufficient for the calculation of the knot polynomial for any given knot or link.

Made available in DSpace on 2015-03-26T13:45:36Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1441623 bytes, checksum: 546ade192993fd13d15e3039ab577882 (MD5) Previous issue date: 2013-07-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work, we study the classical invariants of Legendrian Knots Theory and we show that these are not complet. To do this we introduce a notion of a Basic Knot Theory like their classical invariants, Thurston-Bennequin number and Maslov number. Then we discuss a new tool developed by Chekanon and denoted by DGA (Differential Graduated Algebra), wich will help us in the proof of the incompletness of classical invariants of legendrian knots. / Neste trabalho, estudaremos os invariantes clássicos da Teoria de Nós Legendreanos e mostraremos que estes não são completos. Para tal introduzimos uma noção básica da Teoria de Nós Legendreanos, assim como seus invariantes clássicos, o número de Thurston-Bennequin e o número de Maslov. Em seguida discutiremos uma nova ferramenta desenvolvida por Chekanov, a Álgebra Diferencial Graduada, denotada por DGA (Differential Graduated Algebra), que nos auxiliar na prova da incompletude dos invariantes clássicos de nós legendreanos.