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xii | |
| I CODES FROM ALGEBRAIC CURVES |
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3 | (86) |
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1 Introduction: curves and codes |
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3 | (4) |
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2 The introduction of coordinates. |
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3 The use of algebraic structures. |
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5 Codes found by evaluating functions. |
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6 Codes and algebraic curves. |
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8 Notational conventions. |
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7 | (14) |
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2 Irreducible polynomials in K[x, y]. |
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3 Unique factorization in K[x, y]. |
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4 Increasing the supply of curves. |
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5 Absolute irreducibility. |
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6 Existence of absolutely irreducible polynomials. |
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7 Projective transformations. |
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8 Final definition of a curve. |
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9 Curves over finite fields. |
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10 An example of a cubic curve. |
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3 Functions on algebraic curves |
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21 | (17) |
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5 Independence of coordinate system. |
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6 Evaluating functions at points. |
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7 Shifting to the origin. |
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8 Divisibility by x - Alpha |
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11 Good orders and simple points. |
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12 A test for singularity. |
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15 The degree of a point. |
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4 A survey of the theory of algebraic curves |
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38 | (10) |
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2 Counting poles and zeros. |
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4 Applying the horizon theorem. |
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7 Riemann's theorem and the genus. |
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8 The Plucker formula for smooth plane curves. |
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48 | (12) |
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1 Error-correcting codes. |
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4 Parameters of function codes. |
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5 Points of the Klein quartic. |
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7 Generator and check matrices. |
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8 Parameters of residue codes. |
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60 | (11) |
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3 Finding an error locator. |
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4 Conditions for the SV-algorithm. |
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5 The Skorobogatov-Vladut error processing algorithm. |
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8 A comparison with Reed-Solomon codes. |
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71 | (18) |
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3 Existence of error locators. |
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4 Testing for error locators. |
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7 The Duursma error processing algorithm. |
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| II FIELDS OF ALGEBRAIC FUNCTIONS |
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89 | (95) |
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8 Introduction: the algebraic approach |
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89 | (2) |
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9 Function fields and places |
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91 | (10) |
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1 Function fields of plane curves. |
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3 The field defined by an irreducible polynomial. |
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4 Places of a function field F. |
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5 Places of the field of rational functions. |
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7 The existence of places. |
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101 | (10) |
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2 Valuations and point orders. |
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3 Valuation rings and places. |
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4 Valuation rings determine valuations. |
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5 Places are valuation rings. |
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6 The approximation theorem. |
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7 Places of F over a given place of K(x). |
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111 | (14) |
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4 Elements of F as functions on places. |
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6 Finiteness of the rank of a divisor. |
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7 The divisor of zeros of a function. |
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8 A lower bound for the rank of a divisor of zeros. |
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11 Riemann's theorem and the genus. |
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12 Rational function fields. |
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12 Repartitions and differentials |
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125 | (17) |
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5 Relative dimensions again. |
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6 The index of a divisor. |
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7 The weak Riemann-Roch theorem. |
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9 Properties of the index. |
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10 The divisor of a differential. |
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11 Differentials as multiples. |
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12 The strong Riemann-Roch theorem. |
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13 The strong approximation theorem. |
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16 The residue representation of geometric Goppa codes. |
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17 Goppa codes are dual Goppa codes. |
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13 Extensions of function fields |
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142 | (19) |
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1 Change of base field: the genus. |
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2 Change of base field: differentials. |
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3 Constant field extensions. |
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4 The genus of constant field extensions. |
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5 Places in an extension field. |
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8 Affine rings of extension fields. |
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11 Repartitions of an extension. |
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13 Extending differentials. |
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14 The genus of a separable extension. |
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16 Inseparable extensions. |
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17 Subfields of rational function fields. |
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14 Curves and function fields |
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161 | (13) |
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3 The field of constants of K(C). |
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7 The zeros theorem and singular points. |
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10 Extending the base field. |
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11 Plucker's formula for the genus. |
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12 Plucker's formula is exact for smooth curves. |
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174 | (10) |
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1 The volume of a ball of radius r. |
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2 The simple Gilbert bound. |
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3 The relative minimum distance. |
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5 The relation between entropy and volume. |
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6 The asymptotic Gilbert bound. |
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7 Geometric Goppa codes and the Gilbert bound. |
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8 The theorem of Tsfasman, Vladut, and Zink. |
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10 The curves of Garcia and Stichtenoth. |
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| References |
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184 | (3) |
| Index |
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187 | |