Knowledge (XXG)

Topological game

Source đź“ť

102:
and statistical games, and defines and studies topological games within topology. After more than 35 years, the term “topological game” became widespread, and appeared in several hundreds of publications. The survey paper of Telgársky emphasizes the origin of topological games from the
70:, completeness and convergence properties, separation properties, covering and base properties, continuous images, Suslin sets, and singular spaces. At the same time, some topological properties that arise naturally in topological games can be generalized beyond a 733: 98:, the concept of “topological properties defined by games”, was introduced in the paper of Rastislav Telgársky, and later "spaces defined by topological games"; this approach is based on analogies with matrix games, 74:
context: by virtue of this duality, topological games have been widely used to describe new properties of topological spaces, and to put known properties under a different light. There are also close links with
1025: 962:. Play continues in this fashion, with players alternately picking a nonempty open subset of the previous play. After an infinite sequence of moves, one for each natural number, the game is finished, and 1263:
C. Berge, Topological games with perfect information. Contributions to the theory of games, vol. 3, 165–178. Annals of Mathematics Studies, no. 39. Princeton University Press, Princeton, N. J., 1957.
321: 1294:
R. Telgársky, On topological properties defined by games, Topics in Topology (Proc. Colloq. Keszthely 1972), Colloq. Math. Soc. János Bolyai, Vol. 8, North-Holland, Amsterdam 1974, 617–624.
960: 916: 386: 862:
The first topological game studied was the Banach–Mazur game, which is a motivating example of the connections between game-theoretic notions and topological properties.
800: 559: 412: 360: 157:
in his invited address . The number of moves in these games is always finite. The discovery or rediscovery of these topological games goes back to years 1948–49.
972: 62:
It turns out that some fundamental topological constructions have a natural counterpart in topological games; examples of these are the
51:
lengths, and extensions to continuum time have been put forth. The conditions for a player to win can involve notions like
1282: 283: 1348: 1353: 130: 1244: 1225: 1185: 925: 419: 857: 266: 104: 1069: 888: 1316: 1193: 123: 1205: 1169: 265:
The game is defined by the target property and the allowed moves at each step. For example, in the
76: 52: 28: 728:{\displaystyle s(\lambda ),J_{0},s(J_{0}),J_{1},s(J_{0},J_{1}),J_{2},s(J_{0},J_{1},J_{2}),\ldots } 365: 1209: 779: 48: 1180:
coreduction principle; separation and reduction properties of sets in close projective classes;
1154: 1096: 1058: 326:
This typical setup can be modified in various ways. For example, instead of being a subset of
99: 91: 32: 1229: 1217: 1146: 391: 134: 1272:
C. Berge, Théorie des jeux à n personnes, Mém. des Sc. Mat., Gauthier-Villars, Paris 1957.
333: 1329: 1201: 815: 167: 1121: 415: 119: 110:
There are two other meanings of topological games, but these are used less frequently.
71: 63: 44: 1235:
For a longer list and a more detailed account see the 1987 survey paper of Telgársky.
1342: 1181: 142: 1213: 1197: 1135: 87: 1328:
L. A. Petrosjan, Topological games and their applications to pursuit problems. I.
1303:
R. Telgársky, Spaces defined by topological games, Fund. Math. 88 (1975), 193–223.
56: 1176:
Many more games have been introduced over the years, to study, among others: the
1030:
The game-theoretic and topological connections demonstrated by the game include:
1221: 1128: 1117: 1050: 276:), the allowed moves are nonempty open subsets of the previous move, and player 138: 67: 40: 20: 1189: 1177: 1081: 1054: 154: 36: 126:
games. The trajectories in these topological games are continuous in time.
146: 1317:"Topological Games: On the 50th Anniversary of the Banach-Mazur Game" 35:. Players choose objects with topological properties such as points, 491:
is a function defined over every legal finite sequence of moves of
1020:{\displaystyle X\cap \bigcap _{n\in \omega }I_{n}\neq \emptyset .} 414:. Alternatively, the sequence of moves might have length some 90:, who defined the basic ideas and formalism in analogy with 1168:
chooses a member or finite subset of that collection. See
1208:. Topological games have also been related to ideas in 542:
on the sequence of their opponent's prior moves. So if
181:, who alternately pick subsets of a topological space 975: 928: 891: 782: 562: 394: 368: 336: 286: 47:. Time is generally discrete, but the plays may have 843:
if it depends both on the last move of the opponent
1037:has a winning strategy in the game if and only if 1019: 954: 910: 885:begins the game by picking a nonempty open subset 794: 727: 406: 380: 354: 315: 145:games (projective plane games), and Gale's games ( 173:The typical setup is a game between two players, 1311: 1309: 818:that there are non-determined topological games. 316:{\displaystyle \bigcap _{n}I_{n}\neq \emptyset } 1220:, infinite strings of alternating quantifiers, 743:. (Here λ denotes the empty sequence of moves.) 495:s opponent. For example, a strategy for player 802:. If either player has a winning strategy for 258:satisfies some property, and otherwise player 1319:, Rocky Mountain J. Math. 17 (1987), 227–276. 8: 1170:Selection principle § Topological games 215:. There is a round for every natural number 166:Many frameworks can be defined for infinite 1124:— a modification of the Banach–Mazur game; 1112:Some other notable topological games are: 478:is either a win or a loss for each player. 219:, and after all rounds are played, player 1002: 986: 974: 946: 933: 927: 896: 890: 781: 710: 697: 684: 665: 649: 636: 617: 601: 582: 561: 393: 367: 335: 301: 291: 285: 756:if for every play according to strategy 435:of the game is a sequence of legal moves 206:, and player II responds with a subset 16:Mathematical game on a topological space 1256: 1164:chooses a (topological) collection and 829:if it depends only on the last move by 1141:the point-open game — in which player 1131:— played on a subset of the real line; 1076:has a winning strategy if and only if 922:responds with a nonempty open subset 764:, for any sequence of legal moves by 7: 1160:selection games — each round player 955:{\displaystyle J_{0}\subseteq I_{0}} 330:, each move might consist of a pair 1281:A. R. Pears, On topological games, 1011: 847:on the ordinal number of the move. 310: 162:Basic setup for a topological game 14: 1084:in some nonempty open subset of 1057:if it is the countable union of 911:{\displaystyle I_{0}\subseteq Y} 869:be a topological space, and let 772:has a winning strategy for game 31:played between two players on a 1103:, then the game is determined. 786: 716: 677: 655: 629: 607: 594: 572: 566: 530:. A game is said to be played 349: 337: 1: 1138:— related to siftable spaces; 122:in the study of antagonistic 1283:Proc. Cambridge Philos. Soc. 760:results in a win for player 381:{\displaystyle I\subseteq X} 795:{\displaystyle P\uparrow G} 1370: 855: 833:s opponent; a strategy is 94:. A different meaning for 546:is a strategy for player 1218:infinitely-long formulas 426:Definitions and notation 170:of perfect information. 86:was first introduced by 1108:Other topological games 741:according to strategy s 532:according to strategy s 27:is an infinite game of 1226:partially ordered sets 1186:descriptive set theory 1021: 956: 912: 796: 768:s opponent. If player 748:A strategy for player 729: 408: 407:{\displaystyle p\in x} 382: 356: 317: 1070:complete metric space 1022: 957: 913: 852:The Banach–Mazur game 797: 730: 538:move is the value of 409: 383: 357: 355:{\displaystyle (I,p)} 318: 223:wins if the sequence 141:games (Y games), the 1232:of infinite graphs. 1206:computable functions 1194:closed graph theorem 973: 966:wins if and only if 926: 889: 814:It follows from the 780: 560: 392: 366: 334: 284: 77:selection principles 1332:10 (1972), 194–202. 1285:61 (1965), 165–171. 149:games) were called 53:topological closure 29:perfect information 1245:Topological puzzle 1210:mathematical logic 1184:sieves; invariant 1155:open neighborhoods 1059:nowhere-dense sets 1017: 997: 952: 908: 792: 776:, this is denoted 725: 404: 378: 352: 313: 296: 100:differential games 92:topological groups 1349:Topological games 1200:; MP-spaces; the 1097:property of Baire 1049:(a set is of the 982: 858:Banach–Mazur game 287: 267:Banach–Mazur game 189:th round, player 151:topological games 105:Banach–Mazur game 33:topological space 1361: 1354:General topology 1333: 1326: 1320: 1313: 1304: 1301: 1295: 1292: 1286: 1279: 1273: 1270: 1264: 1261: 1230:chromatic number 1026: 1024: 1023: 1018: 1007: 1006: 996: 961: 959: 958: 953: 951: 950: 938: 937: 917: 915: 914: 909: 901: 900: 840: 839: 801: 799: 798: 793: 734: 732: 731: 726: 715: 714: 702: 701: 689: 688: 670: 669: 654: 653: 641: 640: 622: 621: 606: 605: 587: 586: 534:if every player 526:) to subsets of 503:from sequences ( 476:result of a play 413: 411: 410: 405: 387: 385: 384: 379: 361: 359: 358: 353: 322: 320: 319: 314: 306: 305: 295: 168:positional games 116:topological game 96:topological game 84:topological game 25:topological game 1369: 1368: 1364: 1363: 1362: 1360: 1359: 1358: 1339: 1338: 1337: 1336: 1330:SIAM J. Control 1327: 1323: 1314: 1307: 1302: 1298: 1293: 1289: 1280: 1276: 1271: 1267: 1262: 1258: 1253: 1241: 1202:axiom of choice 1110: 998: 971: 970: 942: 929: 924: 923: 892: 887: 886: 873:be a subset of 860: 854: 837: 836: 821:A strategy for 816:axiom of choice 778: 777: 706: 693: 680: 661: 645: 632: 613: 597: 578: 558: 557: 525: 516: 509: 468: 461: 454: 447: 428: 390: 389: 364: 363: 332: 331: 297: 282: 281: 253: 246: 239: 232: 214: 201: 193:plays a subset 164: 124:pursuit–evasion 17: 12: 11: 5: 1367: 1365: 1357: 1356: 1351: 1341: 1340: 1335: 1334: 1321: 1315:R. Telgársky, 1305: 1296: 1287: 1274: 1265: 1255: 1254: 1252: 1249: 1248: 1247: 1240: 1237: 1174: 1173: 1158: 1139: 1132: 1125: 1120:introduced by 1109: 1106: 1105: 1104: 1089: 1062: 1051:first category 1043:first category 1028: 1027: 1016: 1013: 1010: 1005: 1001: 995: 992: 989: 985: 981: 978: 949: 945: 941: 936: 932: 907: 904: 899: 895: 856:Main article: 853: 850: 849: 848: 819: 810:is said to be 791: 788: 785: 752:is said to be 745: 744: 737: 736: 735: 724: 721: 718: 713: 709: 705: 700: 696: 692: 687: 683: 679: 676: 673: 668: 664: 660: 657: 652: 648: 644: 639: 635: 631: 628: 625: 620: 616: 612: 609: 604: 600: 596: 593: 590: 585: 581: 577: 574: 571: 568: 565: 552: 551: 521: 514: 507: 499:is a function 480: 479: 472: 471: 470: 466: 459: 452: 445: 437: 436: 427: 424: 416:ordinal number 403: 400: 397: 377: 374: 371: 351: 348: 345: 342: 339: 312: 309: 304: 300: 294: 290: 256: 255: 251: 244: 237: 230: 210: 197: 163: 160: 159: 158: 127: 120:Leon Petrosjan 118:introduced by 72:game-theoretic 64:Baire property 45:open coverings 15: 13: 10: 9: 6: 4: 3: 2: 1366: 1355: 1352: 1350: 1347: 1346: 1344: 1331: 1325: 1322: 1318: 1312: 1310: 1306: 1300: 1297: 1291: 1288: 1284: 1278: 1275: 1269: 1266: 1260: 1257: 1250: 1246: 1243: 1242: 1238: 1236: 1233: 1231: 1227: 1223: 1219: 1215: 1211: 1207: 1203: 1199: 1198:webbed spaces 1195: 1191: 1187: 1183: 1179: 1171: 1167: 1163: 1159: 1156: 1152: 1148: 1144: 1140: 1137: 1133: 1130: 1126: 1123: 1119: 1115: 1114: 1113: 1107: 1102: 1098: 1094: 1090: 1087: 1083: 1079: 1075: 1071: 1067: 1063: 1060: 1056: 1052: 1048: 1044: 1040: 1036: 1033: 1032: 1031: 1014: 1008: 1003: 999: 993: 990: 987: 983: 979: 976: 969: 968: 967: 965: 947: 943: 939: 934: 930: 921: 918:, and player 905: 902: 897: 893: 884: 880: 877:, called the 876: 872: 868: 863: 859: 851: 846: 842: 841: 832: 828: 824: 820: 817: 813: 809: 805: 789: 783: 775: 771: 767: 763: 759: 755: 751: 747: 746: 742: 738: 722: 719: 711: 707: 703: 698: 694: 690: 685: 681: 674: 671: 666: 662: 658: 650: 646: 642: 637: 633: 626: 623: 618: 614: 610: 602: 598: 591: 588: 583: 579: 575: 569: 563: 556: 555: 554: 553: 549: 545: 541: 537: 533: 529: 524: 520: 513: 506: 502: 498: 494: 490: 486: 482: 481: 477: 473: 465: 458: 451: 444: 441: 440: 439: 438: 434: 430: 429: 425: 423: 421: 417: 401: 398: 395: 375: 372: 369: 346: 343: 340: 329: 324: 307: 302: 298: 292: 288: 279: 275: 271: 268: 263: 261: 250: 243: 236: 229: 226: 225: 224: 222: 218: 213: 209: 205: 200: 196: 192: 188: 184: 180: 176: 171: 169: 161: 156: 152: 148: 144: 140: 136: 132: 129:The games of 128: 125: 121: 117: 113: 112: 111: 108: 106: 101: 97: 93: 89: 85: 80: 78: 73: 69: 65: 60: 58: 54: 50: 46: 42: 38: 34: 30: 26: 22: 1324: 1299: 1290: 1277: 1268: 1259: 1234: 1222:ultrafilters 1214:model theory 1175: 1165: 1161: 1150: 1142: 1136:Choquet game 1111: 1100: 1092: 1085: 1077: 1073: 1065: 1046: 1042: 1038: 1034: 1029: 963: 919: 882: 878: 874: 870: 866: 864: 861: 844: 835: 834: 830: 826: 822: 811: 807: 803: 773: 769: 765: 761: 757: 753: 749: 740: 547: 543: 539: 535: 531: 527: 522: 518: 511: 504: 500: 496: 492: 488: 484: 475: 463: 456: 449: 442: 432: 327: 325: 277: 273: 269: 264: 259: 257: 248: 241: 234: 227: 220: 216: 211: 207: 203: 198: 194: 190: 186: 182: 178: 174: 172: 165: 150: 115: 109: 95: 88:Claude Berge 83: 81: 68:Baire spaces 61: 24: 18: 1190:Suslin sets 1149:and player 1129:Banach game 1118:binary game 879:winning set 812:determined. 487:for player 418:other than 57:convergence 49:transfinite 41:closed sets 21:mathematics 1343:Categories 1251:References 1228:, and the 1178:Kuratowski 1041:is of the 827:stationary 550:, the play 155:David Gale 1012:∅ 1009:≠ 994:ω 991:∈ 984:⋂ 980:∩ 940:⊆ 903:⊆ 881:. Player 787:↑ 723:… 570:λ 399:∈ 373:⊆ 311:∅ 308:≠ 289:⋂ 185:. In the 135:Hex games 114:The term 82:The term 37:open sets 1239:See also 1157:of them; 1153:chooses 1145:chooses 1095:has the 1082:comeagre 485:strategy 280:wins if 147:Bridg-It 1072:, then 806:, then 754:winning 517:, ..., 143:Shapley 137:), the 1192:; the 1147:points 1055:meagre 838:Markov 362:where 262:wins. 139:Milnor 1182:Luzin 1068:is a 133:(the 1134:the 1127:the 1122:Ulam 1116:the 865:Let 474:The 469:,... 433:play 388:and 254:,... 177:and 131:Nash 55:and 43:and 23:, a 1099:in 1091:If 1080:is 1064:If 1053:or 1045:in 845:and 825:is 739:is 202:of 153:by 19:In 1345:: 1308:^ 1224:, 1216:, 1212:, 1204:; 1196:; 1188:; 1166:II 1151:II 1061:). 1035:II 920:II 831:P' 766:P' 510:, 493:P' 483:A 462:, 455:, 448:, 431:A 422:. 323:. 270:BM 260:II 247:, 240:, 233:, 179:II 107:. 79:. 66:, 59:. 39:, 1172:. 1162:I 1143:I 1101:Y 1093:X 1088:. 1086:Y 1078:X 1074:I 1066:Y 1047:Y 1039:X 1015:. 1004:n 1000:I 988:n 977:X 964:I 948:0 944:I 935:0 931:J 906:Y 898:0 894:I 883:I 875:Y 871:X 867:Y 823:P 808:G 804:G 790:G 784:P 774:G 770:P 762:P 758:s 750:P 720:, 717:) 712:2 708:J 704:, 699:1 695:J 691:, 686:0 682:J 678:( 675:s 672:, 667:2 663:J 659:, 656:) 651:1 647:J 643:, 638:0 634:J 630:( 627:s 624:, 619:1 615:J 611:, 608:) 603:0 599:J 595:( 592:s 589:, 584:0 580:J 576:, 573:) 567:( 564:s 548:I 544:s 540:s 536:P 528:X 523:n 519:J 515:1 512:J 508:0 505:J 501:s 497:I 489:P 467:1 464:J 460:1 457:I 453:0 450:J 446:0 443:I 420:ω 402:x 396:p 376:X 370:I 350:) 347:p 344:, 341:I 338:( 328:X 303:n 299:I 293:n 278:I 274:X 272:( 252:1 249:J 245:1 242:I 238:0 235:J 231:0 228:I 221:I 217:n 212:n 208:J 204:X 199:n 195:I 191:I 187:n 183:X 175:I

Index

mathematics
perfect information
topological space
open sets
closed sets
open coverings
transfinite
topological closure
convergence
Baire property
Baire spaces
game-theoretic
selection principles
Claude Berge
topological groups
differential games
Banach–Mazur game
Leon Petrosjan
pursuit–evasion
Nash
Hex games
Milnor
Shapley
Bridg-It
David Gale
positional games
Banach–Mazur game
ordinal number
ω
axiom of choice

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑