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Higman's embedding theorem

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On the other hand, it is an easy theorem that every finitely generated subgroup of a finitely presented group is recursively presented, so the recursively presented finitely generated groups are (up to isomorphism) exactly the finitely generated subgroups of finitely presented groups.
97:. Indeed, it is fairly easy to construct a finitely generated recursively presented group with undecidable word problem. Then any finitely presented group that contains this group as a subgroup will have undecidable word problem as well. 157: 89:
Higman's embedding theorem also implies the Novikov-Boone theorem (originally proved in the 1950s by other methods) about the existence of a
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finitely presented groups as subgroups (up to isomorphism); in fact, its finitely generated subgroups are exactly the finitely generated
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Proceedings of the Royal Society. Series A. Mathematical and Physical Sciences. vol. 262 (1961), pp. 455-475.
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group is a subgroup of a finitely generated group, the theorem can be restated for those groups.
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Springer-Verlag, New York, 2001. "Classics in Mathematics" series, reprint of the 1977 edition.
153: 145: 169: 101: 53: 141: 24: 71: 64: 42: 112:which can be shown to have a finite presentation. 100:The usual proof of the theorem uses a sequence of 8: 130:Subgroups of finitely presented groups. 121: 7: 76:universal finitely presented group 14: 93:with algorithmically undecidable 1: 86:(again, up to isomorphism). 84:recursively presented groups 150:Combinatorial Group Theory. 36:recursively presented group 18:Universal embedding theorem 197: 29:Higman's embedding theorem 15: 181:Theorems in group theory 108:and ending with a group 91:finitely presented group 47:finitely presented group 16:Not to be confused with 52:. This is a result of 176:Infinite group theory 41:can be embedded as a 33:finitely generated 31:states that every 158:978-3-540-41158-1 188: 160: 139: 133: 126: 56:from the 1960s. 196: 195: 191: 190: 189: 187: 186: 185: 166: 165: 164: 163: 142:Roger C. Lyndon 140: 136: 128:Graham Higman, 127: 123: 118: 21: 12: 11: 5: 194: 192: 184: 183: 178: 168: 167: 162: 161: 146:Paul E. Schupp 134: 120: 119: 117: 114: 104:starting with 102:HNN extensions 78:that contains 13: 10: 9: 6: 4: 3: 2: 193: 182: 179: 177: 174: 173: 171: 159: 155: 151: 147: 143: 138: 135: 131: 125: 122: 115: 113: 111: 107: 103: 98: 96: 92: 87: 85: 81: 77: 74:, there is a 73: 68: 66: 61: 57: 55: 54:Graham Higman 51: 48: 44: 40: 37: 34: 30: 26: 19: 149: 137: 129: 124: 109: 105: 99: 95:word problem 88: 79: 75: 69: 63:Since every 62: 58: 49: 38: 28: 25:group theory 22: 170:Categories 116:References 72:corollary 65:countable 45:of some 43:subgroup 156:  70:As a 154:ISBN 144:and 80:all 23:In 172:: 148:. 27:, 110:G 106:R 50:G 39:R 20:.

Index

Universal embedding theorem
group theory
finitely generated
recursively presented group
subgroup
finitely presented group
Graham Higman
countable
corollary
recursively presented groups
finitely presented group
word problem
HNN extensions
Roger C. Lyndon
Paul E. Schupp
ISBN
978-3-540-41158-1
Categories
Infinite group theory
Theorems in group theory

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