Knowledge

Homeomorphism

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to a point is impermissible, for instance. It is thus important to realize that it is the formal definition given above that counts. In this case, for example, the line segment possesses infinitely many points, and therefore cannot be put into a bijection with a set containing only a finite number of
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are not. However, this description can be misleading. Some continuous deformations do not result into homeomorphisms, such as the deformation of a line into a point. Some homeomorphisms do not result from continuous deformations, such as the homeomorphism between a
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deforms. In the case of homotopy, the continuous deformation from one map to the other is of the essence, and it is also less restrictive, since none of the maps involved need to be one-to-one or onto. Homotopy does lead to a relation on spaces:
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The intuitive criterion of stretching, bending, cutting and gluing back together takes a certain amount of practice to apply correctly—it may not be obvious from the description above that deforming a
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to another, rather than one space to another. In the case of a homeomorphism, envisioning a continuous deformation is a mental tool for keeping track of which points on space
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by creating a dimple and progressively enlarging it, while preserving the donut hole in the mug's handle. This illustrates that a coffee mug and a donut (
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are homeomorphic; since the unit disc can be deformed into the unit square. An example of a bicontinuous mapping from the square to the disc is, in
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There is a name for the kind of deformation involved in visualizing a homeomorphism. It is (except when cutting and regluing are required) an
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Similarly, as usual in category theory, given two spaces that are homeomorphic, the space of homeomorphisms between them,
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In some contexts, there are homeomorphic objects that cannot be continuously deformed from one to the other.
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object, and a homeomorphism results from a continuous deformation of the object into a new shape. Thus, a
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Differential Equations: A Dynamical Systems Approach. Part II: Higher-Dimensional Systems
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This characterization of a homeomorphism often leads to a confusion with the concept of
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are equivalence relations that have been introduced for dealing with such situations.
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is a homeomorphism from a topological space onto itself. Being "homeomorphic" is an
100: 44:"Topological equivalence" redirects here. For the concept in dynamical systems, see 2687: 2633: 2534: 1573: 303: 124: 2126:
will coincide. Note however that this does not extend to properties defined via a
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while other such mappings are given by scaled and translated versions of the
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but the points it maps to numbers in between lie outside the neighbourhood.
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is a homeomorphism between the domain of the parametrization and the curve.
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of a given space. Two spaces with a homeomorphism between them are called
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This function is bijective and continuous, but not a homeomorphism (
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are not homeomorphic because one is compact while the other is not.
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of this point also includes points that the function maps close to
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Mapping which preserves all topological properties of a given space
2445:. Translated by Stillwell, John. American Mathematical Society. 2346: â€“ Continuous deformation between two continuous functions 1011: 163: 159: 1178:
Continuous mappings are not always realizable as deformations.
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Papers on Topology: Analysis Situs and Its Five Supplements
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can be extended to a self-homeomorphism of the whole disk
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with a single point removed and the set of all points in
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is that topologists cannot tell the difference between a
2296: â€“ Mathematical function revertible near each point 1955:
is not homeomorphic to the unit circle as a subspace of
2520:"On Homeomorphism Groups and the Compact-Open Topology" 2319:
Pages displaying short descriptions of redirect targets
2317: â€“ Distance-preserving mathematical transformation 610:{\textstyle f(\varphi )=(\cos \varphi ,\sin \varphi ).} 2417:. Journal de l'Ecole polytechnique. Gauthier-Villars. 1460: 1367: 1282: 1253: 1192: 1051: 1020: 976: 920: 880: 843: 816: 784: 754: 719: 689: 654: 623: 561: 470: 436: 147:, and from a topological viewpoint they are the same. 2189: 2162: 2066: 2034: 2000: 1963: 1913: 1880: 1827: 1795: 1763: 1734: 1698: 1674: 1636: 1603: 1435: 1400: 1229: 1150: 1105: 1085: 530: 393: 373: 341: 311: 281: 247: 204: 183:
are precise definitions for the informal concept of
1340:{\textstyle f(x)={\frac {1}{a-x}}+{\frac {1}{b-x}}} 464:, is essential. Consider for instance the function 2202: 2175: 2084: 2052: 2015: 1978: 1928: 1895: 1855: 1813: 1781: 1749: 1720: 1680: 1651: 1618: 1536: 1415: 1380: 1339: 1268: 1237: 1210: 1168: 1114: 1091: 1071: 1037: 1002: 940: 892: 855: 825: 802: 770: 740: 705: 675: 636: 609: 545: 510: 452: 399: 379: 347: 327: 287: 253: 222: 2989: 1466: 948:This group can be given a topology, such as the 150:Very roughly speaking, a topological space is a 2302: â€“ Isomorphism of differentiable manifolds 2114:, then the other is as well; if one of them is 2110:, then the other is as well; if one of them is 1595:is a homeomorphism between the unit sphere in 2604: 2465: 952:, which under certain assumptions makes it a 1079:and, given a specific homeomorphism between 2381:Hubbard, John H.; West, Beverly H. (1995). 2380: 2972: 2945: 2611: 2597: 2240:as a continuous deformation, but from one 1138:is homeomorphic to a solid torus, but not 2003: 1966: 1916: 1883: 1639: 1606: 1403: 1231: 1153: 533: 2517: 2440: 2407: 1584:of the manifold and an open subset of a 1129: 50: 30:For homeomorphisms in graph theory, see 2556:from the original on 16 September 2016. 2492: 2102:Two homeomorphic spaces share the same 14: 2990: 2466:Gamelin, T. W.; Greene, R. E. (1999). 2218: 363:A homeomorphism is sometimes called a 162:are homeomorphic to each other, but a 2592: 2358: â€“ Theorem in geometric topology 2137:A homeomorphism is simultaneously an 367:function. If such a function exists, 2518:Dijkstra, Jan J. (1 December 2005). 238:if it has the following properties: 2472:(2nd ed.). Dover. p. 67. 2118:, then the other is as well; their 1867: 71:could be reshaped to the form of a 24: 2229:points, including a single point. 1728:is a homeomorphism. Also, for any 99:meaning "similar shape", named by 25: 3019: 2564: 2527:The American Mathematical Monthly 2106:. For example, if one of them is 2025:but the real line is not compact. 1856:{\displaystyle y\mapsto xyx^{-1}} 1169:{\displaystyle \mathbb {R} ^{3}.} 1003:{\textstyle {\text{Homeo}}(X,Y),} 511:{\textstyle f:[0,2\pi )\to S^{1}} 2971: 2944: 2934: 2924: 2913: 2903: 2902: 2696: 2252:—one just follows them as 2016:{\displaystyle \mathbb {R} ^{2}} 1979:{\displaystyle \mathbb {R} ^{2}} 1929:{\displaystyle \mathbb {R} ^{n}} 1896:{\displaystyle \mathbb {R} ^{m}} 1652:{\displaystyle \mathbb {R} ^{2}} 1619:{\displaystyle \mathbb {R} ^{3}} 1416:{\displaystyle \mathbb {R} ^{2}} 546:{\displaystyle \mathbb {R} ^{2}} 1721:{\displaystyle x\mapsto x^{-1}} 1122:all three sets are identified. 1072:{\textstyle {\text{Homeo}}(Y),} 941:{\textstyle {\text{Homeo}}(X).} 713:is not continuous at the point 67:, since a sufficiently pliable 2998:Theory of continuous functions 2511: 2486: 2459: 2401: 2374: 2248:correspond to which points on 2079: 2067: 2047: 2035: 2028:The one-dimensional intervals 1831: 1799: 1767: 1702: 1580:is a homeomorphism between an 1513: 1509: 1495: 1487: 1473: 1469: 1451: 1448: 1436: 1292: 1286: 1205: 1193: 1063: 1057: 1038:{\textstyle {\text{Homeo}}(X)} 1032: 1026: 994: 982: 932: 926: 884: 872:category of topological spaces 797: 785: 732: 720: 670: 655: 601: 577: 571: 565: 495: 492: 477: 214: 133:category of topological spaces 13: 1: 2367: 2096: 1014:for the homeomorphism groups 190: 135:—that is, they are the 2618: 2338:Homeomorphism (graph theory) 2156:Every self-homeomorphism in 1814:{\displaystyle y\mapsto yx,} 1782:{\displaystyle y\mapsto xy,} 1238:{\displaystyle \mathbb {R} } 430:The third requirement, that 32:Homeomorphism (graph theory) 7: 2577:Encyclopedia of Mathematics 2287: 2276:and the homeomorphism from 1992:as a subspace of Euclidean 1988:, since the unit circle is 1821:and the inner automorphism 1125: 419:on topological spaces. Its 10: 3024: 2865:Banach fixed-point theorem 2321:is an isomorphism between 43: 36: 29: 2898: 2855: 2819: 2705: 2694: 2626: 1938:are not homeomorphic for 127:. Homeomorphisms are the 87:and more specifically in 2497:. Limes RY. p. 63. 2469:Introduction to Topology 2441:PoincarĂ©, Henri (2010). 1593:stereographic projection 223:{\displaystyle f:X\to Y} 37:Not to be confused with 2493:Väisälä, Jussi (1999). 2362:Universal homeomorphism 1750:{\displaystyle x\in G,} 1554:is homeomorphic to the 1552:differentiable function 1218:is homeomorphic to the 866:Homeomorphisms are the 105:topological isomorphism 3003:Functions and mappings 2920:Mathematics portal 2820:Metrics and properties 2806:Second-countable space 2204: 2177: 2104:topological properties 2086: 2054: 2017: 1980: 1930: 1897: 1857: 1815: 1789:the right translation 1783: 1751: 1722: 1682: 1653: 1620: 1538: 1417: 1382: 1341: 1270: 1239: 1212: 1179: 1170: 1116: 1093: 1073: 1039: 1004: 942: 894: 857: 827: 804: 772: 742: 707: 683:is not). The function 677: 676:{\textstyle [0,2\pi )} 638: 611: 547: 512: 454: 401: 381: 349: 329: 328:{\displaystyle f^{-1}} 289: 255: 224: 185:continuous deformation 141:topological properties 139:that preserve all the 123:that has a continuous 80: 2315:Isometric isomorphism 2205: 2203:{\displaystyle D^{2}} 2178: 2176:{\displaystyle S^{1}} 2134:and the other is not. 2087: 2085:{\displaystyle (0,1)} 2055: 2018: 1981: 1931: 1898: 1858: 1816: 1784: 1757:the left translation 1752: 1723: 1683: 1654: 1621: 1539: 1418: 1383: 1342: 1271: 1240: 1213: 1171: 1133: 1117: 1094: 1074: 1040: 1005: 950:compact-open topology 943: 895: 858: 828: 805: 773: 743: 708: 678: 639: 612: 548: 513: 455: 425:homeomorphism classes 402: 382: 350: 330: 290: 256: 225: 109:bicontinuous function 54: 46:Topological conjugacy 2875:Invariance of domain 2827:Euler characteristic 2801:Bundle (mathematics) 2259:homotopy equivalence 2236:, which is actually 2187: 2160: 2064: 2032: 1998: 1961: 1911: 1878: 1825: 1793: 1761: 1732: 1696: 1692:, its inversion map 1672: 1634: 1601: 1433: 1398: 1365: 1280: 1269:{\textstyle a<b.} 1251: 1227: 1190: 1148: 1103: 1083: 1049: 1018: 974: 918: 878: 841: 814: 782: 752: 717: 687: 652: 621: 559: 528: 468: 434: 417:equivalence relation 391: 371: 339: 309: 279: 245: 202: 2885:Tychonoff's theorem 2880:PoincarĂ© conjecture 2634:General (point-set) 2356:PoincarĂ© conjecture 2350:Mapping class group 2328:Homeomorphism group 2306:Uniform isomorphism 2294:Local homeomorphism 2219:Informal discussion 2145:; that is, it maps 1863:are homeomorphisms. 907:homeomorphism group 893:{\textstyle X\to X} 856:{\textstyle 2\pi ,} 771:{\textstyle f^{-1}} 741:{\textstyle (1,0),} 706:{\textstyle f^{-1}} 453:{\textstyle f^{-1}} 421:equivalence classes 117:continuous function 79:) are homeomorphic. 2870:De Rham cohomology 2791:Polyhedral complex 2781:Simplicial complex 2200: 2173: 2082: 2050: 2013: 1976: 1926: 1893: 1853: 1811: 1779: 1747: 1718: 1678: 1649: 1616: 1534: 1518: 1413: 1381:{\textstyle D^{2}} 1378: 1337: 1266: 1235: 1211:{\textstyle (a,b)} 1208: 1180: 1166: 1115:{\displaystyle Y,} 1112: 1089: 1069: 1035: 1000: 938: 890: 853: 823: 803:{\textstyle (1,0)} 800: 768: 738: 703: 673: 637:{\textstyle S^{1}} 634: 607: 543: 508: 450: 413:self-homeomorphism 397: 377: 345: 325: 285: 251: 232:topological spaces 220: 121:topological spaces 81: 55:An often-repeated 2985: 2984: 2774:fundamental group 2479:978-0-486-40680-0 2452:978-0-8218-5234-7 2394:978-0-387-94377-0 2212:Alexander's trick 2149:to open sets and 1690:topological group 1681:{\displaystyle G} 1661:(a 2-dimensional 1561:A differentiable 1517: 1427:polar coordinates 1335: 1314: 1092:{\displaystyle X} 1055: 1024: 980: 954:topological group 924: 748:because although 400:{\displaystyle Y} 380:{\displaystyle X} 348:{\displaystyle f} 288:{\displaystyle f} 254:{\displaystyle f} 57:mathematical joke 16:(Redirected from 3015: 2975: 2974: 2948: 2947: 2938: 2928: 2918: 2917: 2906: 2905: 2700: 2613: 2606: 2599: 2590: 2589: 2585: 2558: 2557: 2555: 2539:10.2307/30037630 2524: 2515: 2509: 2508: 2490: 2484: 2483: 2463: 2457: 2456: 2438: 2436: 2434: 2425:. Archived from 2405: 2399: 2398: 2378: 2344:Homotopy#Isotopy 2320: 2209: 2207: 2206: 2201: 2199: 2198: 2182: 2180: 2179: 2174: 2172: 2171: 2091: 2089: 2088: 2083: 2059: 2057: 2056: 2053:{\displaystyle } 2051: 2024: 2022: 2020: 2019: 2014: 2012: 2011: 2006: 1987: 1985: 1983: 1982: 1977: 1975: 1974: 1969: 1948: 1937: 1935: 1933: 1932: 1927: 1925: 1924: 1919: 1904: 1902: 1900: 1899: 1894: 1892: 1891: 1886: 1868:Counter-examples 1862: 1860: 1859: 1854: 1852: 1851: 1820: 1818: 1817: 1812: 1788: 1786: 1785: 1780: 1756: 1754: 1753: 1748: 1727: 1725: 1724: 1719: 1717: 1716: 1687: 1685: 1684: 1679: 1660: 1658: 1656: 1655: 1650: 1648: 1647: 1642: 1627: 1625: 1623: 1622: 1617: 1615: 1614: 1609: 1558:of the function. 1543: 1541: 1540: 1535: 1530: 1526: 1519: 1516: 1512: 1498: 1490: 1476: 1461: 1424: 1422: 1420: 1419: 1414: 1412: 1411: 1406: 1387: 1385: 1384: 1379: 1377: 1376: 1354: 1350: 1346: 1344: 1343: 1338: 1336: 1334: 1320: 1315: 1313: 1299: 1275: 1273: 1272: 1267: 1246: 1244: 1242: 1241: 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2572:"Homeomorphism" 2570: 2567: 2562: 2561: 2553: 2533:(10): 910–912. 2522: 2516: 2512: 2505: 2491: 2487: 2480: 2464: 2460: 2453: 2439: 2432: 2430: 2429:on 11 June 2016 2406: 2402: 2395: 2379: 2375: 2370: 2318: 2290: 2221: 2194: 2190: 2188: 2185: 2184: 2167: 2163: 2161: 2158: 2157: 2153:to closed sets. 2124:homology groups 2099: 2065: 2062: 2061: 2033: 2030: 2029: 2007: 2002: 2001: 1999: 1996: 1995: 1993: 1970: 1965: 1964: 1962: 1959: 1958: 1956: 1939: 1920: 1915: 1914: 1912: 1909: 1908: 1906: 1887: 1882: 1881: 1879: 1876: 1875: 1873: 1870: 1844: 1840: 1826: 1823: 1822: 1794: 1791: 1790: 1762: 1759: 1758: 1733: 1730: 1729: 1709: 1705: 1697: 1694: 1693: 1673: 1670: 1669: 1643: 1638: 1637: 1635: 1632: 1631: 1629: 1610: 1605: 1604: 1602: 1599: 1598: 1596: 1586:Euclidean space 1563:parametrization 1508: 1494: 1486: 1472: 1465: 1459: 1458: 1454: 1434: 1431: 1430: 1407: 1402: 1401: 1399: 1396: 1395: 1393: 1372: 1368: 1366: 1363: 1362: 1352: 1348: 1324: 1319: 1303: 1298: 1281: 1278: 1277: 1252: 1249: 1248: 1230: 1228: 1225: 1224: 1222: 1191: 1188: 1187: 1157: 1152: 1151: 1149: 1146: 1145: 1143: 1128: 1104: 1101: 1100: 1084: 1081: 1080: 1052: 1050: 1047: 1046: 1021: 1019: 1016: 1015: 977: 975: 972: 971: 921: 919: 916: 915: 879: 876: 875: 842: 839: 838: 826:{\textstyle 0,} 815: 812: 811: 783: 780: 779: 759: 755: 753: 750: 749: 718: 715: 714: 694: 690: 688: 685: 684: 653: 650: 649: 628: 624: 622: 619: 618: 560: 557: 556: 537: 532: 531: 529: 526: 525: 523: 502: 498: 469: 466: 465: 441: 437: 435: 432: 431: 392: 389: 388: 372: 369: 368: 340: 337: 336: 335:is continuous ( 316: 312: 310: 307: 306: 280: 277: 276: 246: 243: 242: 203: 200: 199: 193: 103:), also called 49: 42: 35: 28: 23: 22: 15: 12: 11: 5: 3021: 3011: 3010: 3008:Homeomorphisms 3005: 3000: 2983: 2982: 2980: 2979: 2969: 2968: 2967: 2962: 2957: 2942: 2932: 2922: 2910: 2899: 2896: 2895: 2893: 2892: 2887: 2882: 2877: 2872: 2867: 2861: 2859: 2853: 2852: 2850: 2849: 2844: 2839: 2837:Winding number 2834: 2829: 2823: 2821: 2817: 2816: 2814: 2813: 2808: 2803: 2798: 2793: 2788: 2783: 2778: 2777: 2776: 2771: 2769:homotopy group 2761: 2760: 2759: 2754: 2749: 2744: 2739: 2729: 2724: 2719: 2709: 2707: 2703: 2702: 2695: 2693: 2691: 2690: 2685: 2680: 2679: 2678: 2668: 2667: 2666: 2656: 2651: 2646: 2641: 2636: 2630: 2628: 2624: 2623: 2616: 2615: 2608: 2601: 2593: 2587: 2586: 2566: 2565:External links 2563: 2560: 2559: 2510: 2503: 2485: 2478: 2458: 2451: 2414:Analysis Situs 2400: 2393: 2372: 2371: 2369: 2366: 2365: 2364: 2359: 2353: 2347: 2341: 2335: 2330: 2325: 2312: 2310:uniform spaces 2303: 2300:Diffeomorphism 2297: 2289: 2286: 2220: 2217: 2216: 2215: 2197: 2193: 2170: 2166: 2154: 2143:closed mapping 2135: 2098: 2095: 2094: 2093: 2081: 2078: 2075: 2072: 2069: 2049: 2046: 2043: 2040: 2037: 2026: 2010: 2005: 1973: 1968: 1951:The Euclidean 1949: 1923: 1918: 1890: 1885: 1869: 1866: 1865: 1864: 1850: 1847: 1843: 1839: 1836: 1833: 1830: 1810: 1807: 1804: 1801: 1798: 1778: 1775: 1772: 1769: 1766: 1746: 1743: 1740: 1737: 1715: 1712: 1708: 1704: 1701: 1677: 1666: 1646: 1641: 1613: 1608: 1589: 1570: 1559: 1544: 1533: 1529: 1525: 1522: 1515: 1511: 1507: 1504: 1501: 1497: 1493: 1489: 1485: 1482: 1479: 1475: 1471: 1468: 1464: 1457: 1453: 1450: 1447: 1444: 1441: 1438: 1410: 1405: 1375: 1371: 1356: 1333: 1330: 1327: 1323: 1318: 1312: 1309: 1306: 1302: 1297: 1294: 1291: 1288: 1285: 1265: 1262: 1259: 1256: 1233: 1207: 1204: 1201: 1198: 1195: 1165: 1160: 1155: 1127: 1124: 1111: 1108: 1088: 1068: 1065: 1062: 1059: 1034: 1031: 1028: 999: 996: 993: 990: 987: 984: 937: 934: 931: 928: 889: 886: 883: 852: 849: 846: 822: 819: 799: 796: 793: 790: 787: 765: 762: 758: 737: 734: 731: 728: 725: 722: 700: 697: 693: 672: 669: 666: 663: 660: 657: 631: 627: 606: 603: 600: 597: 594: 591: 588: 585: 582: 579: 576: 573: 570: 567: 564: 540: 535: 505: 501: 497: 494: 491: 488: 485: 482: 479: 476: 473: 447: 444: 440: 396: 376: 361: 360: 344: 322: 319: 315: 300: 284: 274: 250: 219: 216: 213: 210: 207: 192: 189: 175:and a circle. 101:Henri PoincarĂ© 26: 9: 6: 4: 3: 2: 3020: 3009: 3006: 3004: 3001: 2999: 2996: 2995: 2993: 2978: 2970: 2966: 2963: 2961: 2958: 2956: 2953: 2952: 2951: 2943: 2941: 2937: 2933: 2931: 2927: 2923: 2921: 2916: 2911: 2909: 2901: 2900: 2897: 2891: 2888: 2886: 2883: 2881: 2878: 2876: 2873: 2871: 2868: 2866: 2863: 2862: 2860: 2858: 2854: 2848: 2847:Orientability 2845: 2843: 2840: 2838: 2835: 2833: 2830: 2828: 2825: 2824: 2822: 2818: 2812: 2809: 2807: 2804: 2802: 2799: 2797: 2794: 2792: 2789: 2787: 2784: 2782: 2779: 2775: 2772: 2770: 2767: 2766: 2765: 2762: 2758: 2755: 2753: 2750: 2748: 2745: 2743: 2740: 2738: 2735: 2734: 2733: 2730: 2728: 2725: 2723: 2720: 2718: 2714: 2711: 2710: 2708: 2704: 2699: 2689: 2686: 2684: 2683:Set-theoretic 2681: 2677: 2674: 2673: 2672: 2669: 2665: 2662: 2661: 2660: 2657: 2655: 2652: 2650: 2647: 2645: 2644:Combinatorial 2642: 2640: 2637: 2635: 2632: 2631: 2629: 2625: 2621: 2614: 2609: 2607: 2602: 2600: 2595: 2594: 2591: 2583: 2579: 2578: 2573: 2569: 2568: 2552: 2548: 2544: 2540: 2536: 2532: 2528: 2521: 2514: 2506: 2504:951-745-184-9 2500: 2496: 2489: 2481: 2475: 2471: 2470: 2462: 2454: 2448: 2444: 2428: 2424: 2420: 2416: 2415: 2410: 2404: 2396: 2390: 2386: 2385: 2377: 2373: 2363: 2360: 2357: 2354: 2351: 2348: 2345: 2342: 2339: 2336: 2334: 2331: 2329: 2326: 2324: 2323:metric spaces 2316: 2313: 2311: 2307: 2304: 2301: 2298: 2295: 2292: 2291: 2285: 2283: 2279: 2275: 2271: 2267: 2262: 2260: 2255: 2251: 2247: 2243: 2239: 2235: 2230: 2227: 2213: 2195: 2191: 2168: 2164: 2155: 2152: 2148: 2144: 2140: 2136: 2133: 2129: 2125: 2121: 2117: 2113: 2109: 2105: 2101: 2100: 2076: 2073: 2070: 2044: 2041: 2038: 2027: 2008: 1991: 1971: 1954: 1950: 1946: 1942: 1921: 1888: 1872: 1871: 1848: 1845: 1841: 1837: 1834: 1828: 1808: 1805: 1802: 1796: 1776: 1773: 1770: 1764: 1744: 1741: 1738: 1735: 1713: 1710: 1706: 1699: 1691: 1675: 1667: 1664: 1644: 1611: 1594: 1590: 1587: 1583: 1579: 1575: 1571: 1568: 1564: 1560: 1557: 1553: 1549: 1545: 1531: 1527: 1523: 1520: 1505: 1502: 1499: 1491: 1483: 1480: 1477: 1462: 1455: 1445: 1442: 1439: 1428: 1408: 1391: 1373: 1369: 1361: 1357: 1331: 1328: 1325: 1321: 1316: 1310: 1307: 1304: 1300: 1295: 1289: 1283: 1263: 1260: 1257: 1254: 1221: 1202: 1199: 1196: 1186: 1182: 1181: 1163: 1158: 1141: 1137: 1132: 1123: 1109: 1106: 1086: 1066: 1060: 1029: 1013: 997: 991: 988: 985: 968: 966: 962: 957: 955: 951: 935: 929: 913: 909: 908: 904:, called the 903: 887: 881: 873: 869: 864: 850: 847: 844: 836: 835:neighbourhood 820: 817: 794: 791: 788: 763: 760: 756: 735: 729: 726: 723: 698: 695: 691: 667: 664: 661: 658: 647: 629: 625: 604: 598: 595: 592: 589: 586: 583: 580: 574: 568: 562: 538: 521: 503: 499: 489: 486: 483: 480: 474: 471: 463: 445: 442: 438: 428: 426: 422: 418: 414: 410: 394: 374: 366: 358: 342: 320: 317: 313: 305: 301: 298: 282: 275: 272: 268: 264: 248: 241: 240: 239: 237: 236:homeomorphism 233: 217: 211: 208: 205: 198: 188: 186: 182: 178: 174: 169: 165: 161: 157: 153: 148: 146: 142: 138: 134: 130: 126: 122: 118: 114: 110: 106: 102: 98: 94: 93:homeomorphism 90: 86: 78: 74: 70: 66: 62: 58: 53: 47: 40: 33: 19: 2977:Publications 2842:Chern number 2832:Betti number 2715: / 2706:Key concepts 2654:Differential 2575: 2530: 2526: 2513: 2494: 2488: 2468: 2461: 2442: 2431:. Retrieved 2427:the original 2413: 2409:PoincarĂ©, H. 2403: 2383: 2376: 2281: 2277: 2273: 2270:identity map 2268:between the 2263: 2253: 2249: 2245: 2241: 2237: 2231: 2226:line segment 2222: 2139:open mapping 1944: 1940: 1220:real numbers 1136:trefoil knot 1134:A thickened 969: 958: 911: 905: 868:isomorphisms 865: 555:) defined by 429: 424: 412: 409:homeomorphic 408: 365:bicontinuous 364: 362: 357:open mapping 235: 230:between two 194: 184: 173:trefoil knot 149: 145:homeomorphic 144: 129:isomorphisms 108: 104: 92: 82: 39:homomorphism 18:Homeomorphic 2940:Wikiversity 2857:Key results 2495:Topologia I 2151:closed sets 1582:open subset 1390:unit square 1358:The unit 2- 1355:functions). 520:unit circle 423:are called 85:mathematics 2992:Categories 2786:CW complex 2727:Continuity 2717:Closed set 2676:cohomology 2368:References 2333:Dehn twist 2097:Properties 462:continuous 297:continuous 267:one-to-one 191:Definition 73:coffee mug 61:coffee mug 2965:geometric 2960:algebraic 2811:Cobordism 2747:Hausdorff 2742:connected 2659:Geometric 2649:Continuum 2639:Algebraic 2582:EMS Press 2423:715734142 2147:open sets 2116:Hausdorff 2112:connected 1953:real line 1846:− 1832:↦ 1800:↦ 1768:↦ 1739:∈ 1711:− 1703:↦ 1524:θ 1506:θ 1503:⁡ 1484:θ 1481:⁡ 1463:ρ 1452:↦ 1446:θ 1440:ρ 1329:− 1308:− 1183:The open 885:→ 848:π 761:− 696:− 668:π 599:φ 596:⁡ 587:φ 584:⁡ 569:φ 496:→ 490:π 443:− 318:− 263:bijection 215:→ 152:geometric 113:bijective 2930:Wikibook 2908:Category 2796:Manifold 2764:Homotopy 2722:Interior 2713:Open set 2671:Homology 2620:Topology 2551:Archived 2547:30037630 2433:29 April 2411:(1895). 2288:See also 2242:function 2234:homotopy 2132:complete 2120:homotopy 1943:≠ 1578:manifold 1388:and the 1353:arg tanh 1247:for any 1185:interval 1140:isotopic 1126:Examples 961:Homotopy 900:forms a 197:function 177:Homotopy 137:mappings 119:between 89:topology 2955:general 2757:uniform 2737:compact 2688:Digital 2584:, 2001 2266:isotopy 2238:defined 2108:compact 2023:⁠ 1994:⁠ 1990:compact 1986:⁠ 1957:⁠ 1936:⁠ 1907:⁠ 1903:⁠ 1874:⁠ 1659:⁠ 1630:⁠ 1626:⁠ 1597:⁠ 1423:⁠ 1394:⁠ 1245:⁠ 1223:⁠ 1176:⁠ 1144:⁠ 965:isotopy 870:in the 646:compact 553:⁠ 524:⁠ 181:isotopy 131:in the 111:, is a 2950:Topics 2752:metric 2627:Fields 2545:  2501:  2476:  2449:  2421:  2391:  2141:and a 2128:metric 1556:domain 1012:torsor 355:is an 166:and a 164:sphere 160:circle 158:and a 156:square 63:and a 2732:Space 2554:(PDF) 2543:JSTOR 2523:(PDF) 1688:is a 1663:plane 1576:of a 1574:chart 1567:curve 1565:of a 1550:of a 1548:graph 1054:Homeo 1023:Homeo 1010:is a 979:Homeo 963:and 923:Homeo 902:group 778:maps 518:(the 261:is a 234:is a 168:torus 107:, or 77:torus 69:donut 65:donut 2499:ISBN 2474:ISBN 2447:ISBN 2435:2018 2419:OCLC 2389:ISBN 2122:and 2060:and 1905:and 1591:The 1546:The 1360:disc 1258:< 1142:in 1099:and 1045:and 833:any 648:but 411:. A 407:are 387:and 302:the 271:onto 269:and 179:and 115:and 91:, a 2535:doi 2531:112 2280:to 2272:on 1668:If 1500:sin 1478:cos 1467:max 1392:in 1351:or 1349:tan 910:of 810:to 644:is 593:sin 581:cos 522:in 460:be 295:is 83:In 2994:: 2580:, 2574:, 2549:. 2541:. 2529:. 2525:. 2284:. 2261:. 2214:). 1665:). 1572:A 1429:, 956:. 427:. 359:). 273:), 195:A 187:. 2612:e 2605:t 2598:v 2537:: 2507:. 2482:. 2455:. 2437:. 2397:. 2282:Y 2278:X 2274:X 2254:X 2250:Y 2246:X 2210:( 2196:2 2192:D 2169:1 2165:S 2080:) 2077:1 2074:, 2071:0 2068:( 2048:] 2045:1 2042:, 2039:0 2036:[ 2009:2 2004:R 1972:2 1967:R 1947:. 1945:n 1941:m 1922:n 1917:R 1889:m 1884:R 1849:1 1842:x 1838:y 1835:x 1829:y 1809:, 1806:x 1803:y 1797:y 1777:, 1774:y 1771:x 1765:y 1745:, 1742:G 1736:x 1714:1 1707:x 1700:x 1676:G 1645:2 1640:R 1612:3 1607:R 1588:. 1532:. 1528:) 1521:, 1514:) 1510:| 1496:| 1492:, 1488:| 1474:| 1470:( 1456:( 1449:) 1443:, 1437:( 1409:2 1404:R 1374:2 1370:D 1332:x 1326:b 1322:1 1317:+ 1311:x 1305:a 1301:1 1296:= 1293:) 1290:x 1287:( 1284:f 1264:. 1261:b 1255:a 1232:R 1206:) 1203:b 1200:, 1197:a 1194:( 1164:. 1159:3 1154:R 1110:, 1107:Y 1087:X 1067:, 1064:) 1061:Y 1058:( 1033:) 1030:X 1027:( 998:, 995:) 992:Y 989:, 986:X 983:( 936:. 933:) 930:X 927:( 912:X 888:X 882:X 851:, 845:2 821:, 818:0 798:) 795:0 792:, 789:1 786:( 764:1 757:f 736:, 733:) 730:0 727:, 724:1 721:( 699:1 692:f 671:) 665:2 662:, 659:0 656:[ 630:1 626:S 605:. 602:) 590:, 578:( 575:= 572:) 566:( 563:f 539:2 534:R 504:1 500:S 493:) 487:2 484:, 481:0 478:[ 475:: 472:f 446:1 439:f 395:Y 375:X 343:f 321:1 314:f 299:, 283:f 265:( 249:f 218:Y 212:X 209:: 206:f 95:( 48:. 41:. 34:. 20:)

Index

Homeomorphic
Homeomorphism (graph theory)
homomorphism
Topological conjugacy

mathematical joke
coffee mug
donut
donut
coffee mug
torus
mathematics
topology
from Greek roots
Henri Poincaré
bijective
continuous function
topological spaces
inverse function
isomorphisms
category of topological spaces
mappings
topological properties
geometric
square
circle
sphere
torus
trefoil knot
Homotopy

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