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Escaping set

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Eremenko also asked whether every escaping point can be connected to infinity by a curve in the escaping set; it was later shown that this is not the case. Indeed, there exist entire functions whose escaping sets do not contain any curves at all.
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Note that the final statement does not imply Eremenko's Conjecture. (Indeed, there exist connected spaces in which the removal of a single
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For a transcendental entire function, the escaping set always intersects the Julia set. In particular, the escaping set is
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The following properties are known to hold for the escaping set of any non-constant and non-linear entire function. (Here
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of this fixed point, and hence usually referred to as the **basin of infinity**. In this case,
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of the escaping set of a transcendental entire function is unbounded. This has become known as
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The first study of the escaping set for a general transcendental entire function is due to
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in 1926 The escaping set occurs implicitly in his study of the explicit entire functions
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Sixsmith, D.J. (2012). "Entire functions for which the escaping set is a spider's web".
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Can the escaping set of a transcendental entire function have a bounded component?
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Rippon, P. J.; Stallard, G (2011). "Boundaries of escaping Fatou components".
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Every connected component of the closure of the escaping set is unbounded.
1466: 1295:; Schleicher, D (2011). "Dynamic rays of bounded-type entire functions". 1292: 1233: 1216: 1101: 1097:
Plotting algorithms for the Mandelbrot set § Escape time algorithm
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The escaping set always has at least one unbounded connected component.
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The iteration of transcendental entire functions was first studied by
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belongs to the escaping set if and only if the sequence defined by
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The escaping set is connected or has infinitely many components.
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Mathematical Proceedings of the Cambridge Philosophical Society
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consists precisely of the complement of the closed unit disc:
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Lipham, D.S. (2022). "Exponential iteration and Borel sets".
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See (Eremenko, 1989), formula (1) on p. 339 and l.2 of p. 340
845: 830:{\displaystyle I(f)=\{z\in \mathbb {C} \colon |z|>1\}.} 28:ƒ consists of all points that tend to infinity under the 1217:"Sur l'itération des fonctions transcendantes Entières" 1063: 1025: 997: 968: 931: 855: 769: 724: 677: 599: 567: 497: 396: 334: 248: 203: 171: 151: 131: 76: 41: 659:of degree 2 extends to an analytic self-map of the 1079: 1049: 1010: 981: 952: 893: 840: 829: 752: 692: 642:leaves the remaining space totally disconnected.) 626: 573: 527: 432: 382: 305: 231: 186: 157: 137: 117: 62: 1479: 1420:(2020). "Escaping sets are not sigma-compact". 953:{\displaystyle F_{\sigma \delta }{\text{ set}}} 667:at infinity. The escaping set is precisely the 444: 1334: 1174: 539:The escaping set contains at least one point. 821: 785: 621: 615: 306:{\displaystyle 0,1,e,e^{e},e^{e^{e}},\dots } 550:. In particular, the escaping set is never 491:means that the function is not of the form 1446: 1425: 1385: 1348: 1308: 1232: 1196: 1019:. For functions in the exponential class 795: 56: 1371: 1269:Banach Center Publications, Warsawa, PWN 1256: 844: 1465: 454:(more unsolved problems in mathematics) 1480: 1440: 1286: 1284: 1282: 1262:"On the iteration of entire functions" 924:By definition, the escaping set is an 1416: 1330: 1328: 1211: 715:For instance the escaping set of the 708:subset of the complex plane, and the 63:{\displaystyle z_{0}\in \mathbb {C} } 1205: 1181:"On questions of Fatou and Eremenko" 1170: 1168: 1166: 1164: 627:{\displaystyle I(f)\cup \{\infty \}} 1279: 1252: 1250: 1248: 1246: 1244: 546:of the escaping set is exactly the 13: 1325: 1080:{\displaystyle G_{\delta \sigma }} 618: 14: 1499: 1459: 1161: 383:{\displaystyle f(z)=z+1+\exp(-z)} 118:{\displaystyle z_{n+1}:=f(z_{n})} 16:In mathematics, and particularly 1241: 145:gets large. The escaping set of 1471:"A poem on Eremenko conjecture" 1434: 1410: 1365: 1359:10.1090/s0002-9939-2011-10842-6 907:transcendental entire functions 841:Transcendental entire functions 712:is the boundary of this basin. 445:Unsolved problem in mathematics 1141: 1132: 1123: 1114: 1038: 1032: 880: 871: 865: 856: 811: 803: 779: 773: 734: 728: 687: 681: 650: 609: 603: 507: 501: 427: 421: 406: 400: 377: 368: 344: 338: 213: 207: 181: 175: 112: 99: 1: 1198:10.1090/s0002-9939-04-07805-0 1154: 1147:Theorem 3 of (Eremenko, 1989) 1138:Theorem 2 of (Eremenko, 1989) 1120:Theorem 1 of (Eremenko, 1989) 894:{\displaystyle (\exp(z)-1)/2} 482: 433:{\displaystyle f(z)=c\sin(z)} 1291:Rottenfußer, G; Rückert, J; 717:complex quadratic polynomial 665:super-attracting fixed point 467:. He conjectured that every 7: 1319:10.4007/annals.2010.173.1.3 1090: 1011:{\displaystyle F_{\sigma }} 982:{\displaystyle G_{\delta }} 645: 10: 1504: 1057:, the escaping set is not 753:{\displaystyle f(z)=z^{2}} 319: 232:{\displaystyle f(z)=e^{z}} 1404:10.1017/S0305004111000582 1050:{\displaystyle \exp(z)+a} 528:{\displaystyle f(z)=az+b} 125:converges to infinity as 1107: 1081: 1051: 1012: 983: 954: 902: 895: 831: 754: 694: 628: 575: 529: 434: 384: 307: 233: 188: 159: 139: 119: 64: 1337:Proc. Amer. Math. Soc 1185:Proc. Amer. Math. Soc 1082: 1052: 1013: 984: 955: 896: 848: 832: 755: 695: 629: 576: 530: 473:Eremenko's conjecture 435: 385: 308: 234: 189: 160: 140: 120: 65: 1061: 1023: 995: 966: 929: 853: 767: 722: 693:{\displaystyle I(f)} 675: 597: 565: 495: 465:Wiman-Valiron theory 394: 332: 246: 201: 187:{\displaystyle I(f)} 169: 149: 129: 74: 39: 30:repeated application 1396:2011MPCPS.151..551S 669:basin of attraction 469:connected component 316:tends to infinity. 1234:10.1007/bf02559517 1077: 1047: 1008: 979: 950: 903: 891: 827: 750: 690: 624: 571: 525: 461:Alexandre Eremenko 430: 380: 303: 229: 184: 155: 135: 115: 60: 948: 574:{\displaystyle f} 197:For example, for 158:{\displaystyle f} 138:{\displaystyle n} 32:of ƒ. That is, a 1495: 1488:Complex analysis 1474: 1453: 1452: 1450: 1438: 1432: 1431: 1429: 1414: 1408: 1407: 1389: 1369: 1363: 1362: 1352: 1343:(8): 2807–2820. 1332: 1323: 1322: 1312: 1288: 1277: 1276: 1266: 1254: 1239: 1238: 1236: 1209: 1203: 1202: 1200: 1191:(4): 1119–1126. 1172: 1148: 1145: 1139: 1136: 1130: 1127: 1121: 1118: 1086: 1084: 1083: 1078: 1076: 1075: 1056: 1054: 1053: 1048: 1017: 1015: 1014: 1009: 1007: 1006: 988: 986: 985: 980: 978: 977: 961:. It is neither 959: 957: 956: 951: 949: 946: 944: 943: 900: 898: 897: 892: 887: 849:Escaping set of 836: 834: 833: 828: 814: 806: 798: 759: 757: 756: 751: 749: 748: 699: 697: 696: 691: 640:dispersion point 633: 631: 630: 625: 581:is a polynomial. 580: 578: 577: 572: 534: 532: 531: 526: 446: 439: 437: 436: 431: 389: 387: 386: 381: 312: 310: 309: 304: 296: 295: 294: 293: 276: 275: 238: 236: 235: 230: 228: 227: 193: 191: 190: 185: 164: 162: 161: 156: 144: 142: 141: 136: 124: 122: 121: 116: 111: 110: 92: 91: 69: 67: 66: 61: 59: 51: 50: 18:complex dynamics 1503: 1502: 1498: 1497: 1496: 1494: 1493: 1492: 1478: 1477: 1462: 1457: 1456: 1439: 1435: 1415: 1411: 1370: 1366: 1333: 1326: 1289: 1280: 1264: 1255: 1242: 1210: 1206: 1175:Rippon, P. J.; 1173: 1162: 1157: 1152: 1151: 1146: 1142: 1137: 1133: 1128: 1124: 1119: 1115: 1110: 1093: 1068: 1064: 1062: 1059: 1058: 1024: 1021: 1020: 1002: 998: 996: 993: 992: 973: 969: 967: 964: 963: 945: 936: 932: 930: 927: 926: 883: 854: 851: 850: 843: 810: 802: 794: 768: 765: 764: 744: 740: 723: 720: 719: 676: 673: 672: 653: 648: 598: 595: 594: 566: 563: 562: 561:if and only if 496: 493: 492: 485: 457: 456: 451: 448: 395: 392: 391: 333: 330: 329: 322: 289: 285: 284: 280: 271: 267: 247: 244: 243: 223: 219: 202: 199: 198: 170: 167: 166: 150: 147: 146: 130: 127: 126: 106: 102: 81: 77: 75: 72: 71: 55: 46: 42: 40: 37: 36: 26:entire function 12: 11: 5: 1501: 1491: 1490: 1476: 1475: 1461: 1460:External links 1458: 1455: 1454: 1433: 1409: 1380:(3): 551–571. 1364: 1324: 1278: 1240: 1227:(4): 337–370. 1204: 1159: 1158: 1156: 1153: 1150: 1149: 1140: 1131: 1122: 1112: 1111: 1109: 1106: 1105: 1104: 1099: 1092: 1089: 1074: 1071: 1067: 1046: 1043: 1040: 1037: 1034: 1031: 1028: 1005: 1001: 976: 972: 942: 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1392:Bibcode 320:History 700:is an 552:closed 24:of an 20:, the 1443:arXiv 1422:arXiv 1382:arXiv 1345:arXiv 1305:arXiv 1265:(PDF) 1108:Notes 911:hairs 990:nor 915:rays 905:For 816:> 704:and 702:open 559:open 542:The 390:and 1400:doi 1378:151 1355:doi 1341:139 1315:doi 1301:173 1229:doi 1193:doi 1189:133 1027:exp 913:or 860:exp 535:.) 416:sin 363:exp 1484:: 1469:. 1398:. 1390:. 1376:. 1353:. 1339:. 1327:^ 1313:. 1299:. 1281:^ 1273:23 1271:. 1267:. 1243:^ 1225:47 1223:. 1219:. 1187:. 1183:. 1163:^ 1087:. 655:A 440:. 194:. 94::= 1473:. 1451:. 1445:: 1430:. 1424:: 1406:. 1402:: 1394:: 1384:: 1361:. 1357:: 1347:: 1321:. 1317:: 1307:: 1237:. 1231:: 1201:. 1195:: 1066:G 1045:a 1042:+ 1039:) 1036:z 1033:( 1000:F 971:G 934:F 901:. 889:2 885:/ 881:) 878:1 872:) 869:z 866:( 857:( 825:. 822:} 819:1 812:| 808:z 804:| 796:C 789:z 786:{ 783:= 780:) 777:f 774:( 771:I 746:2 742:z 738:= 735:) 732:z 729:( 726:f 688:) 685:f 682:( 679:I 622:} 616:{ 610:) 607:f 604:( 601:I 569:f 554:. 523:b 520:+ 517:z 514:a 511:= 508:) 505:z 502:( 499:f 447:: 428:) 425:z 422:( 413:c 410:= 407:) 404:z 401:( 398:f 378:) 375:z 369:( 360:+ 357:1 354:+ 351:z 348:= 345:) 342:z 339:( 336:f 298:, 291:e 287:e 282:e 278:, 273:e 269:e 265:, 262:e 259:, 256:1 253:, 250:0 225:z 221:e 217:= 214:) 211:z 208:( 205:f 182:) 179:f 176:( 173:I 153:f 133:n 113:) 108:n 104:z 100:( 97:f 89:1 86:+ 83:n 79:z 57:C 48:0 44:z

Index

complex dynamics
entire function
repeated application
complex number
Pierre Fatou
(more unsolved problems in mathematics)
Alexandre Eremenko
Wiman-Valiron theory
connected component
boundary
Julia set
closed
open
dispersion point
polynomial
Riemann sphere
super-attracting fixed point
basin of attraction
open
connected
Julia set
complex quadratic polynomial

transcendental entire functions
F σ δ  set {\displaystyle F_{\sigma \delta }{\text{ set}}}
G δ {\displaystyle G_{\delta }}
F σ {\displaystyle F_{\sigma }}
Plotting algorithms for the Mandelbrot set § Escape time algorithm
target set

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