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Profinite group

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The idea of using a profinite group is to provide a "uniform", or "synoptic", view of an entire system of finite groups. Properties of the profinite group are generally speaking uniform properties of the system. For example, the profinite group is finitely generated (as a topological group) if and
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Nikolov, Nikolay; Segal, Dan (2007). "On finitely generated profinite groups. I: Strong completeness and uniform bounds. II: Products in quasisimple groups".
736:{\displaystyle \varprojlim G_{i}=\left\{(g_{i})_{i\in I}\in {\textstyle \prod \limits _{i\in I}}G_{i}:f_{i}^{j}(g_{j})=g_{i}{\text{ for all }}i\leq j\right\}} 3665: 1635: 4110: 2283: 4506: 1347:
satisfying the axioms in the second definition can be constructed as an inverse limit according to the first definition using the inverse limit
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is given the smallest topology compatible with group operations in which its normal subgroups of finite index are open, there exists a unique
4405: 2658:. The inverse limit of an inverse system of profinite groups with continuous transition maps is profinite and the inverse limit functor is 3240: 3905: 310: 3753: 3186:
is a homeomorphism. Therefore the topology on a topologically finitely generated profinite group is uniquely determined by its
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Nikolov, Nikolay; Segal, Dan (2007), "On finitely generated profinite groups, I: strong completeness and uniform bounds",
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Nikolov, Nikolay; Segal, Dan (2007), "On finitely generated profinite groups, II: products in quasisimple groups",
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of (arbitrarily many) profinite groups is profinite; the topology arising from the profiniteness agrees with the
2098: 4236:. Grundlehren der mathematischen Wissenschaften. Vol. 322. Berlin, Heidelberg: Springer Berlin Heidelberg. 2188: 1847: 968: 4554: 3093:
are topologically finitely generated profinite groups that are isomorphic as discrete groups by an isomorphism
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subgroup of a profinite group is itself profinite; the topology arising from the profiniteness agrees with the
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profinite groups are in duality with locally finite discrete abelian groups. The latter are just the abelian
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elements. Many theorems about finite groups can be readily generalised to profinite groups; examples are
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by inclusion, which translates into an inverse system of natural homomorphisms between the quotients).
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are also profinite groups, roughly speaking because the algebra can only 'see' finite coverings of an
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is topologically finitely generated then it is in addition equal to its own profinite completion.
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of the resulting profinite group; in a sense, these quotients approximate the profinite group.
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of infinite degree gives rise naturally to Galois groups that are profinite. Specifically, if
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Any group constructed by the first definition satisfies the axioms in the second definition.
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on the category of profinite groups. Further, being profinite is an extension property.
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Topological group that is in a certain sense assembled from a system of finite groups
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A subgroup of a profinite group is open if and only if it is closed and has finite
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in one variable over the complex numbers.) Not every profinite group occurs as an
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between them. Without loss of generality, these homomorphisms can be assumed to be
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The topology on this profinite group is the same as the topology arising from the
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where the intersection runs through all normal subgroups of finite index).
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is profinite; the topology arising from the profiniteness agrees with the
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profinite group is isomorphic to one arising from the Galois theory of
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Galois extension. For the limit process, the restriction homomorphisms
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To construct a profinite group one needs a system of finite groups and
4435:, Lecture Notes in Mathematics (in French), vol. 5 (5 ed.), 4152: 4036: 2873: 2869: 1030: 4030:
Segal, Dan (2007-03-29). "Some aspects of profinite group theory".
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is topologically finitely generated. Indeed, any open subgroup of
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In practice, the inverse system of finite groups is almost always
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Profinite groups can be defined in either of two equivalent ways.
3954:{\displaystyle \mathbb {Z} /p^{n}\mathbb {Z} ,n\in \mathbb {N} .} 394:{\displaystyle \{f_{i}^{j}:G_{j}\to G_{i}\mid i,j\in I,i\leq j\}} 3796:{\displaystyle G\cong {\textstyle \prod \limits _{p\in S}}G_{p}} 3329:
is projective if for every surjective morphism from a profinite
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finite groups. In this context, an inverse system consists of a
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is finite. This is equivalent, in fact, to being 'ind-finite'.
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topological group: that is, a topological group that is also a
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is bijective and continuous by the above result. Furthermore,
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the inverse Galois problem is settled, such as the field of
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fixed. This group is the inverse limit of the finite groups
2615:étale fundamental groups considered in algebraic geometry 170:. A non-compact generalization of the concept is that of 3655:{\displaystyle G={\overline {\langle \sigma \rangle }},} 3309:
for every extension. This is equivalent to saying that
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As an easy corollary of the Nikolov–Segal result above,
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In detail, it is the inverse limit of the finite groups
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such that every group in the system can be generated by
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Every projective profinite group can be realized as an
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and the collection satisfies the composition property
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that is in a certain sense assembled from a system of
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if it is topologically generated by a single element
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Pages displaying wikidata descriptions as a fallback
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Pages displaying wikidata descriptions as a fallback
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Pages displaying wikidata descriptions as a fallback
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which allows us to measure the "size" of subsets of
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One can also define the inverse limit in terms of a
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is also of finite index, and hence it must be open.
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Review of several books about profinite groups. 2693:is a closed normal subgroup of a profinite group 879:It is defined as the inverse limit of the groups 194:A profinite group is a topological group that is 117:, in which case the finite groups will appear as 4546: 4507:Proceedings of the American Mathematical Society 2508:will be in this case. In fact, for many fields 1566:). It is the inverse limit of the finite groups 768: 3409:is equivalent to either of the two properties: 3243:.) The usual terminology is different: a group 124:Important examples of profinite groups are the 4504:(1974), "Profinite groups are Galois groups", 3292: 2248:ranges over all intermediate fields such that 1601:{\displaystyle \mathbb {Z} /p^{n}\mathbb {Z} } 4514:(2), American Mathematical Society: 639–640, 4406:Bulletin of the American Mathematical Society 3450:{\displaystyle \operatorname {cd} (G)\leq 1;} 2528:one does not know in general precisely which 1278:{\displaystyle g:{\widehat {G}}\rightarrow H} 4345: 4312: 4137: 3675: 3669: 3640: 3634: 2012:This group is the product of all the groups 388: 314: 284: 259: 4281: 3239:of finite groups. (In particular, it is an 2134:{\displaystyle G=\operatorname {Gal} (L/K)} 4500: 4220:Fried & Jarden (2008) pp. 208,545 2454: 2221:{\displaystyle \operatorname {Gal} (F/K),} 1872:{\displaystyle \mathbb {Z} /n\mathbb {Z} } 1504:Finite groups are profinite, if given the 1002:{\displaystyle \eta :G\to {\widehat {G}},} 4519: 4418: 4369: 4359: 4336: 4326: 4282:Fried, Michael D.; Jarden, Moshe (2008). 4151: 4035: 3944: 3930: 3910: 3882: 3706: 2488:but one cannot (yet) control which field 2436:{\displaystyle \operatorname {Gal} (L/K)} 2021: 1995: 1989: 1965: 1952: 1944: 1931: 1865: 1852: 1827: 1812:{\displaystyle {\widehat {\mathbb {Z} }}} 1799: 1760: 1688: 1668: 1660: 1640: 1594: 1574: 1542: 64: 4399: 4229: 4378: 4266:"MO. decomposition of procyclic groups" 4198: 4196: 3030:is of finite index, so its preimage in 2918:surjective discrete group homomorphism 2644: 788: 14: 4547: 4050: 2909:classification of finite simple groups 1188:and any continuous group homomorphism 1085:is injective if and only if the group 4467: 4427: 4211:Fried & Jarden (2008) p. 207 4190:Fried & Jarden (2008) p. 497 4111:"Inverse limits and profinite groups" 4029: 2883:for topologically finitely generated 2774:is compact Hausdorff, there exists a 2396:{\displaystyle F_{2}\subseteq F_{1}.} 1562:under addition is profinite (in fact 1455: 4205: 4193: 4184: 4108: 4104: 4102: 3194: 1563: 1495:it as its own profinite completion. 4083: 3766: 3389:Projectivity for a profinite group 1432:ordered by (reverse) inclusion. If 816:there is a related profinite group 761:terms, this is a special case of a 640: 24: 4009: – type of mathematical group 3562: 3211:to profinite groups; i.e. a group 2633:whose fundamental group equals it. 1164:is characterized by the following 25: 4571: 4521:10.1090/S0002-9939-1974-0325587-3 4099: 3549:pseudo algebraically closed field 2037:{\displaystyle \mathbb {Z} _{p},} 1776:{\displaystyle \mathbb {Z} _{p}.} 293:{\displaystyle \{G_{i}:i\in I\},} 71:{\displaystyle d\in \mathbb {N} } 3895:{\displaystyle \mathbb {Z} _{p}} 1555:{\displaystyle \mathbb {Z} _{p}} 1213:{\displaystyle f:G\rightarrow H} 965:There is a natural homomorphism 4258: 4223: 4118:University of California, Davis 4000: – concept in group theory 3998:Residual property (mathematics) 3986: – type of profinite group 2943:{\displaystyle \varphi :G\to H} 1819:is the profinite completion of 1381:{\displaystyle \varprojlim G/N} 1058:{\displaystyle {\widehat {G}}.} 841:{\displaystyle {\widehat {G}},} 190:First definition (constructive) 4214: 4131: 4077: 4044: 4023: 3435: 3429: 3368: 3339: 2934: 2430: 2416: 2347: 2326: 2317: 2314: 2293: 2212: 2198: 2128: 2114: 1991: 1948: 1916:{\displaystyle n=1,2,3,\dots } 1664: 1319: 1269: 1204: 981: 698: 685: 619: 605: 567:The inverse limit is the set: 560:{\displaystyle i\leq j\leq k.} 345: 232: 220: 13: 1: 4475:, Translated by Patrick Ion, 4420:10.1090/S0273-0979-01-00914-4 4016: 1837:{\displaystyle \mathbb {Z} .} 769:Second definition (axiomatic) 181: 4051:Wilson, John Stuart (1998). 3750:is procyclic if and only if 3662:the closure of the subgroup 3644: 2754:Since every profinite group 2636:The automorphism group of a 2532:occur as Galois groups over 1168:: given any profinite group 958:(these normal subgroups are 174:. Even more general are the 7: 4371:10.4007/annals.2007.165.239 4338:10.4007/annals.2007.165.171 4162:10.4007/annals.2007.165.171 4055:. Oxford: Clarendon Press. 3963: 3293:Projective profinite groups 3231:is ind-finite if it is the 3159:{\displaystyle \iota ^{-1}} 2877:finitely generated subgroup 1498: 1029:under this homomorphism is 176:totally disconnected groups 10: 4576: 3207:, which is the conceptual 2864:According to a theorem of 2638:locally finite rooted tree 2165:that keep all elements of 241:{\displaystyle (I,\leq ),} 4242:10.1007/978-3-662-03983-0 4230:Neukirch, Jürgen (1999). 2990:is continuous as long as 2950:between profinite groups 2403:The topology obtained on 1310:{\displaystyle f=g\eta .} 1134:{\displaystyle \cap N=1,} 793:Given an arbitrary group 426:{\displaystyle f_{i}^{i}} 162:Every profinite group is 3873:is isomorphic to either 3823:ranges over some set of 3611:{\displaystyle \sigma ;} 3551:. This result is due to 2005:{\displaystyle m\,|\,n.} 1724:{\displaystyle n\geq m.} 1408:ranges through the open 172:locally profinite groups 4433:Cohomologie galoisienne 4403:(2001), "Book Review", 4233:Algebraic Number Theory 4202:Serre (1997) p. 58 4146:(1): 171–238, 239–273. 4007:Residually finite group 3415:cohomological dimension 3380:{\displaystyle G\to H.} 3166:is also continuous, so 3109:{\displaystyle \iota .} 773:A profinite group is a 4502:Waterhouse, William C. 3955: 3896: 3867: 3840: 3817: 3797: 3744: 3722: 3656: 3612: 3581: 3533: 3513: 3493: 3473: 3451: 3403: 3381: 3349: 3348:{\displaystyle H\to G} 3323: 3257: 3225: 3180: 3179:{\displaystyle \iota } 3160: 3130: 3129:{\displaystyle \iota } 3110: 3087: 3067: 3044: 3024: 3004: 2984: 2964: 2944: 2899: 2849: 2818: 2795: 2768: 2741: 2710: 2687: 2596: 2576: 2557:inverse Galois problem 2549: 2522: 2502: 2482: 2437: 2397: 2354: 2270: 2242: 2222: 2179: 2159: 2135: 2085: 2038: 2006: 1973: 1917: 1873: 1838: 1813: 1777: 1745: 1725: 1696: 1622: 1602: 1556: 1526: 1485: 1446: 1426: 1402: 1382: 1341: 1327:Conversely, any group 1311: 1279: 1234: 1214: 1182: 1158: 1135: 1099: 1079: 1059: 1023: 1003: 948: 924: 904: 873: 842: 810: 737: 561: 526: 458: 427: 395: 294: 242: 143: 92: 72: 4555:Infinite group theory 4348:Annals of Mathematics 4315:Annals of Mathematics 3956: 3897: 3868: 3866:{\displaystyle G_{p}} 3841: 3818: 3798: 3745: 3723: 3657: 3613: 3582: 3545:absolute Galois group 3534: 3514: 3494: 3474: 3452: 3404: 3382: 3350: 3324: 3297:A profinite group is 3258: 3226: 3199:There is a notion of 3181: 3161: 3131: 3111: 3088: 3068: 3045: 3025: 3005: 2985: 2965: 2945: 2907:. The proof uses the 2900: 2850: 2819: 2796: 2769: 2742: 2711: 2688: 2608:absolute Galois group 2597: 2577: 2550: 2523: 2503: 2483: 2438: 2398: 2355: 2271: 2243: 2223: 2180: 2160: 2136: 2095:, consider the group 2086: 2046:absolute Galois group 2039: 2007: 1974: 1923:with the modulo maps 1918: 1874: 1839: 1814: 1778: 1746: 1726: 1697: 1632:and the natural maps 1623: 1603: 1557: 1527: 1486: 1447: 1427: 1403: 1383: 1342: 1312: 1280: 1235: 1215: 1183: 1159: 1157:{\displaystyle \eta } 1136: 1100: 1080: 1078:{\displaystyle \eta } 1060: 1024: 1004: 949: 925: 905: 874: 843: 811: 738: 562: 527: 459: 457:{\displaystyle G_{i}} 428: 396: 295: 243: 144: 93: 73: 50:only if there exists 3975:Locally cyclic group 3970:Hausdorff completion 3906: 3877: 3850: 3830: 3807: 3754: 3734: 3730:A topological group 3666: 3622: 3599: 3571: 3523: 3503: 3483: 3463: 3420: 3393: 3362: 3333: 3313: 3247: 3215: 3170: 3140: 3120: 3097: 3077: 3057: 3034: 3014: 2994: 2974: 2954: 2922: 2889: 2836: 2805: 2782: 2758: 2723: 2697: 2677: 2645:Properties and facts 2586: 2563: 2536: 2512: 2492: 2469: 2407: 2364: 2284: 2252: 2232: 2189: 2169: 2149: 2099: 2067: 2016: 1983: 1927: 1883: 1848: 1823: 1792: 1755: 1735: 1706: 1636: 1612: 1570: 1537: 1516: 1472: 1436: 1416: 1392: 1351: 1331: 1289: 1248: 1224: 1192: 1172: 1148: 1113: 1089: 1069: 1037: 1013: 969: 938: 914: 903:{\displaystyle G/N,} 883: 860: 852:profinite completion 820: 797: 789:Profinite completion 779:totally disconnected 571: 536: 468: 441: 405: 311: 256: 217: 168:totally disconnected 133: 82: 54: 4401:Lubotzky, Alexander 3281:, one can see that 2740:{\displaystyle G/N} 2269:{\displaystyle F/K} 2143:field automorphisms 2084:{\displaystyle L/K} 1751:-adic valuation on 1244:group homomorphism 716: for all  684: 521: 503: 485: 422: 331: 155:of infinite-degree 111:group homomorphisms 4560:Topological groups 4469:Serre, Jean-Pierre 4429:Serre, Jean-Pierre 4086:"Profinite Groups" 4084:Lenstra, Hendrik. 3951: 3892: 3863: 3836: 3813: 3793: 3781: 3780: 3740: 3718: 3652: 3608: 3577: 3567:A profinite group 3553:Alexander Lubotzky 3529: 3509: 3489: 3469: 3447: 3399: 3377: 3345: 3319: 3279:Pontryagin duality 3269:finitely generated 3253: 3221: 3176: 3156: 3126: 3106: 3083: 3063: 3040: 3020: 3000: 2980: 2960: 2940: 2895: 2848:{\displaystyle G.} 2845: 2817:{\displaystyle G,} 2814: 2794:{\displaystyle G,} 2791: 2764: 2737: 2709:{\displaystyle G,} 2706: 2683: 2627:algebraic topology 2623:fundamental groups 2604:rational functions 2592: 2575:{\displaystyle K.} 2572: 2548:{\displaystyle K.} 2545: 2518: 2498: 2481:{\displaystyle K,} 2478: 2433: 2393: 2350: 2266: 2238: 2218: 2175: 2155: 2141:consisting of all 2131: 2081: 2034: 2002: 1969: 1913: 1869: 1834: 1809: 1787:profinite integers 1773: 1741: 1721: 1692: 1618: 1598: 1552: 1522: 1484:{\displaystyle G,} 1481: 1456:Surjective systems 1442: 1422: 1398: 1378: 1362: 1337: 1307: 1275: 1230: 1210: 1178: 1166:universal property 1154: 1131: 1095: 1075: 1055: 1019: 999: 944: 920: 900: 872:{\displaystyle G.} 869: 838: 809:{\displaystyle G,} 806: 755:universal property 743:equipped with the 733: 670: 655: 654: 582: 557: 522: 507: 489: 471: 454: 423: 408: 391: 317: 304:, and a family of 290: 238: 139: 100:Lagrange's theorem 88: 68: 4473:Galois cohomology 4446:978-3-540-58002-7 4297:978-3-540-77269-9 4251:978-3-642-08473-7 4109:Osserman, Brian. 4093:Leiden University 3993:Profinite integer 3839:{\displaystyle S} 3816:{\displaystyle p} 3765: 3743:{\displaystyle G} 3647: 3580:{\displaystyle G} 3557:Lou van den Dries 3532:{\displaystyle p} 3512:{\displaystyle G} 3492:{\displaystyle p} 3472:{\displaystyle p} 3402:{\displaystyle G} 3322:{\displaystyle G} 3256:{\displaystyle G} 3224:{\displaystyle G} 3195:Ind-finite groups 3086:{\displaystyle H} 3066:{\displaystyle G} 3043:{\displaystyle G} 3023:{\displaystyle H} 3003:{\displaystyle G} 2983:{\displaystyle H} 2963:{\displaystyle G} 2898:{\displaystyle p} 2881:Jean-Pierre Serre 2767:{\displaystyle G} 2749:quotient topology 2686:{\displaystyle N} 2671:subspace topology 2619:algebraic variety 2595:{\displaystyle K} 2582:(For some fields 2559:for a field  2521:{\displaystyle K} 2501:{\displaystyle K} 2455:Waterhouse (1974) 2241:{\displaystyle F} 2178:{\displaystyle K} 2158:{\displaystyle L} 1806: 1744:{\displaystyle p} 1621:{\displaystyle n} 1525:{\displaystyle p} 1506:discrete topology 1445:{\displaystyle G} 1425:{\displaystyle G} 1401:{\displaystyle N} 1355: 1340:{\displaystyle G} 1266: 1233:{\displaystyle G} 1181:{\displaystyle H} 1144:The homomorphism 1107:residually finite 1098:{\displaystyle G} 1065:The homomorphism 1049: 1022:{\displaystyle G} 1009:and the image of 993: 960:partially ordered 947:{\displaystyle G} 930:runs through the 923:{\displaystyle N} 832: 717: 639: 575: 302:discrete topology 252:of finite groups 142:{\displaystyle p} 91:{\displaystyle d} 40:topological group 16:(Redirected from 4567: 4540: 4523: 4497: 4465: 4423: 4422: 4395: 4391:, talk given at 4390: 4385:Profinite Groups 4380:Lenstra, Hendrik 4374: 4373: 4363: 4341: 4340: 4330: 4309: 4284:Field arithmetic 4274: 4273: 4262: 4256: 4255: 4227: 4221: 4218: 4212: 4209: 4203: 4200: 4191: 4188: 4182: 4181: 4155: 4135: 4129: 4128: 4126: 4120:. Archived from 4115: 4106: 4097: 4096: 4090: 4081: 4075: 4074: 4053:Profinite groups 4048: 4042: 4041: 4039: 4027: 4012: 4003: 3989: 3960: 3958: 3957: 3952: 3947: 3933: 3928: 3927: 3918: 3913: 3901: 3899: 3898: 3893: 3891: 3890: 3885: 3872: 3870: 3869: 3864: 3862: 3861: 3845: 3843: 3842: 3837: 3822: 3820: 3819: 3814: 3802: 3800: 3799: 3794: 3792: 3791: 3782: 3779: 3749: 3747: 3746: 3741: 3727: 3725: 3724: 3719: 3714: 3710: 3709: 3695: 3694: 3661: 3659: 3658: 3653: 3648: 3643: 3632: 3617: 3615: 3614: 3609: 3593: 3592: 3586: 3584: 3583: 3578: 3538: 3536: 3535: 3530: 3518: 3516: 3515: 3510: 3498: 3496: 3495: 3490: 3478: 3476: 3475: 3470: 3459:for every prime 3456: 3454: 3453: 3448: 3408: 3406: 3405: 3400: 3386: 3384: 3383: 3378: 3354: 3352: 3351: 3346: 3328: 3326: 3325: 3320: 3307:lifting property 3303: 3302: 3262: 3260: 3259: 3254: 3237:inductive system 3230: 3228: 3227: 3222: 3205: 3204: 3203:ind-finite group 3185: 3183: 3182: 3177: 3165: 3163: 3162: 3157: 3155: 3154: 3135: 3133: 3132: 3127: 3115: 3113: 3112: 3107: 3092: 3090: 3089: 3084: 3072: 3070: 3069: 3064: 3049: 3047: 3046: 3041: 3029: 3027: 3026: 3021: 3009: 3007: 3006: 3001: 2989: 2987: 2986: 2981: 2969: 2967: 2966: 2961: 2949: 2947: 2946: 2941: 2904: 2902: 2901: 2896: 2854: 2852: 2851: 2846: 2824:compute certain 2823: 2821: 2820: 2815: 2800: 2798: 2797: 2792: 2773: 2771: 2770: 2765: 2746: 2744: 2743: 2738: 2733: 2715: 2713: 2712: 2707: 2692: 2690: 2689: 2684: 2656:product topology 2601: 2599: 2598: 2593: 2581: 2579: 2578: 2573: 2554: 2552: 2551: 2546: 2527: 2525: 2524: 2519: 2507: 2505: 2504: 2499: 2487: 2485: 2484: 2479: 2443:is known as the 2442: 2440: 2439: 2434: 2426: 2402: 2400: 2399: 2394: 2389: 2388: 2376: 2375: 2360:are used, where 2359: 2357: 2356: 2351: 2343: 2338: 2337: 2310: 2305: 2304: 2275: 2273: 2272: 2267: 2262: 2247: 2245: 2244: 2239: 2227: 2225: 2224: 2219: 2208: 2184: 2182: 2181: 2176: 2164: 2162: 2161: 2156: 2140: 2138: 2137: 2132: 2124: 2093:Galois extension 2090: 2088: 2087: 2082: 2077: 2061:field extensions 2043: 2041: 2040: 2035: 2030: 2029: 2024: 2011: 2009: 2008: 2003: 1994: 1978: 1976: 1975: 1970: 1968: 1960: 1955: 1947: 1939: 1934: 1922: 1920: 1919: 1914: 1878: 1876: 1875: 1870: 1868: 1860: 1855: 1843: 1841: 1840: 1835: 1830: 1818: 1816: 1815: 1810: 1808: 1807: 1802: 1797: 1782: 1780: 1779: 1774: 1769: 1768: 1763: 1750: 1748: 1747: 1742: 1730: 1728: 1727: 1722: 1701: 1699: 1698: 1693: 1691: 1686: 1685: 1676: 1671: 1663: 1658: 1657: 1648: 1643: 1628:ranges over all 1627: 1625: 1624: 1619: 1607: 1605: 1604: 1599: 1597: 1592: 1591: 1582: 1577: 1561: 1559: 1558: 1553: 1551: 1550: 1545: 1531: 1529: 1528: 1523: 1490: 1488: 1487: 1482: 1466: 1465: 1451: 1449: 1448: 1443: 1431: 1429: 1428: 1423: 1410:normal subgroups 1407: 1405: 1404: 1399: 1387: 1385: 1384: 1379: 1374: 1363: 1346: 1344: 1343: 1338: 1316: 1314: 1313: 1308: 1284: 1282: 1281: 1276: 1268: 1267: 1259: 1239: 1237: 1236: 1231: 1219: 1217: 1216: 1211: 1187: 1185: 1184: 1179: 1163: 1161: 1160: 1155: 1140: 1138: 1137: 1132: 1104: 1102: 1101: 1096: 1084: 1082: 1081: 1076: 1064: 1062: 1061: 1056: 1051: 1050: 1042: 1028: 1026: 1025: 1020: 1008: 1006: 1005: 1000: 995: 994: 986: 953: 951: 950: 945: 932:normal subgroups 929: 927: 926: 921: 909: 907: 906: 901: 893: 878: 876: 875: 870: 854: 853: 847: 845: 844: 839: 834: 833: 825: 815: 813: 812: 807: 763:cofiltered limit 748:product topology 742: 740: 739: 734: 732: 728: 718: 715: 713: 712: 697: 696: 683: 678: 666: 665: 656: 653: 633: 632: 617: 616: 596: 595: 583: 566: 564: 563: 558: 531: 529: 528: 523: 520: 515: 502: 497: 484: 479: 463: 461: 460: 455: 453: 452: 432: 430: 429: 424: 421: 416: 400: 398: 397: 392: 357: 356: 344: 343: 330: 325: 300:each having the 299: 297: 296: 291: 271: 270: 247: 245: 244: 239: 157:field extensions 148: 146: 145: 140: 97: 95: 94: 89: 77: 75: 74: 69: 67: 21: 4575: 4574: 4570: 4569: 4568: 4566: 4565: 4564: 4545: 4544: 4487: 4477:Springer-Verlag 4447: 4437:Springer-Verlag 4388: 4361:math.GR/0604400 4328:math.GR/0604399 4298: 4288:Springer-Verlag 4278: 4277: 4264: 4263: 4259: 4252: 4228: 4224: 4219: 4215: 4210: 4206: 4201: 4194: 4189: 4185: 4136: 4132: 4124: 4113: 4107: 4100: 4088: 4082: 4078: 4063: 4049: 4045: 4028: 4024: 4019: 4010: 4001: 3987: 3966: 3943: 3929: 3923: 3919: 3914: 3909: 3907: 3904: 3903: 3886: 3881: 3880: 3878: 3875: 3874: 3857: 3853: 3851: 3848: 3847: 3831: 3828: 3827: 3808: 3805: 3804: 3787: 3783: 3769: 3763: 3755: 3752: 3751: 3735: 3732: 3731: 3705: 3690: 3686: 3685: 3681: 3667: 3664: 3663: 3633: 3631: 3623: 3620: 3619: 3600: 3597: 3596: 3590: 3589: 3572: 3569: 3568: 3565: 3563:Procyclic group 3524: 3521: 3520: 3504: 3501: 3500: 3484: 3481: 3480: 3464: 3461: 3460: 3421: 3418: 3417: 3394: 3391: 3390: 3363: 3360: 3359: 3334: 3331: 3330: 3314: 3311: 3310: 3300: 3299: 3295: 3248: 3245: 3244: 3216: 3213: 3212: 3202: 3201: 3197: 3171: 3168: 3167: 3147: 3143: 3141: 3138: 3137: 3121: 3118: 3117: 3098: 3095: 3094: 3078: 3075: 3074: 3058: 3055: 3054: 3035: 3032: 3031: 3015: 3012: 3011: 2995: 2992: 2991: 2975: 2972: 2971: 2955: 2952: 2951: 2923: 2920: 2919: 2890: 2887: 2886: 2866:Nikolay Nikolov 2837: 2834: 2833: 2806: 2803: 2802: 2783: 2780: 2779: 2759: 2756: 2755: 2729: 2724: 2721: 2720: 2698: 2695: 2694: 2678: 2675: 2674: 2647: 2587: 2584: 2583: 2564: 2561: 2560: 2537: 2534: 2533: 2513: 2510: 2509: 2493: 2490: 2489: 2470: 2467: 2466: 2422: 2408: 2405: 2404: 2384: 2380: 2371: 2367: 2365: 2362: 2361: 2339: 2333: 2329: 2306: 2300: 2296: 2285: 2282: 2281: 2258: 2253: 2250: 2249: 2233: 2230: 2229: 2204: 2190: 2187: 2186: 2170: 2167: 2166: 2150: 2147: 2146: 2120: 2100: 2097: 2096: 2073: 2068: 2065: 2064: 2025: 2020: 2019: 2017: 2014: 2013: 1990: 1984: 1981: 1980: 1964: 1956: 1951: 1943: 1935: 1930: 1928: 1925: 1924: 1884: 1881: 1880: 1864: 1856: 1851: 1849: 1846: 1845: 1826: 1824: 1821: 1820: 1798: 1796: 1795: 1793: 1790: 1789: 1764: 1759: 1758: 1756: 1753: 1752: 1736: 1733: 1732: 1707: 1704: 1703: 1687: 1681: 1677: 1672: 1667: 1659: 1653: 1649: 1644: 1639: 1637: 1634: 1633: 1630:natural numbers 1613: 1610: 1609: 1593: 1587: 1583: 1578: 1573: 1571: 1568: 1567: 1546: 1541: 1540: 1538: 1535: 1534: 1517: 1514: 1513: 1501: 1473: 1470: 1469: 1463: 1462: 1458: 1437: 1434: 1433: 1417: 1414: 1413: 1393: 1390: 1389: 1370: 1354: 1352: 1349: 1348: 1332: 1329: 1328: 1322: 1290: 1287: 1286: 1258: 1257: 1249: 1246: 1245: 1225: 1222: 1221: 1193: 1190: 1189: 1173: 1170: 1169: 1149: 1146: 1145: 1114: 1111: 1110: 1090: 1087: 1086: 1070: 1067: 1066: 1041: 1040: 1038: 1035: 1034: 1014: 1011: 1010: 985: 984: 970: 967: 966: 939: 936: 935: 915: 912: 911: 889: 884: 881: 880: 861: 858: 857: 851: 850: 824: 823: 821: 818: 817: 798: 795: 794: 791: 771: 714: 708: 704: 692: 688: 679: 674: 661: 657: 643: 637: 622: 618: 612: 608: 604: 600: 591: 587: 574: 572: 569: 568: 537: 534: 533: 516: 511: 498: 493: 480: 475: 469: 466: 465: 448: 444: 442: 439: 438: 417: 412: 406: 403: 402: 352: 348: 339: 335: 326: 321: 312: 309: 308: 266: 262: 257: 254: 253: 218: 215: 214: 192: 184: 134: 131: 130: 126:additive groups 119:quotient groups 83: 80: 79: 63: 55: 52: 51: 36:profinite group 28: 23: 22: 15: 12: 11: 5: 4573: 4563: 4562: 4557: 4543: 4542: 4498: 4485: 4445: 4425: 4413:(4): 475–479, 4397: 4376: 4354:(1): 239–273, 4350:, 2nd series, 4343: 4321:(1): 171–238, 4317:, 2nd series, 4310: 4296: 4276: 4275: 4257: 4250: 4222: 4213: 4204: 4192: 4183: 4140:Ann. Math. (2) 4130: 4127:on 2018-12-26. 4098: 4076: 4061: 4043: 4021: 4020: 4018: 4015: 4014: 4013: 4004: 3995: 3990: 3977: 3972: 3965: 3962: 3950: 3946: 3942: 3939: 3936: 3932: 3926: 3922: 3917: 3912: 3889: 3884: 3860: 3856: 3835: 3812: 3790: 3786: 3778: 3775: 3772: 3768: 3762: 3759: 3739: 3717: 3713: 3708: 3704: 3701: 3698: 3693: 3689: 3684: 3680: 3677: 3674: 3671: 3651: 3646: 3642: 3639: 3636: 3630: 3627: 3607: 3604: 3594: 3576: 3564: 3561: 3541: 3540: 3528: 3508: 3499:-subgroups of 3488: 3468: 3457: 3446: 3443: 3440: 3437: 3434: 3431: 3428: 3425: 3398: 3376: 3373: 3370: 3367: 3344: 3341: 3338: 3318: 3305:if it has the 3304: 3294: 3291: 3287:torsion groups 3265:locally finite 3252: 3220: 3206: 3196: 3193: 3192: 3191: 3189: 3175: 3153: 3150: 3146: 3125: 3105: 3102: 3082: 3062: 3051: 3039: 3019: 2999: 2979: 2959: 2939: 2936: 2933: 2930: 2927: 2917: 2912: 2894: 2862: 2855: 2844: 2841: 2813: 2810: 2790: 2787: 2763: 2752: 2736: 2732: 2728: 2705: 2702: 2682: 2663: 2646: 2643: 2642: 2641: 2634: 2611: 2591: 2571: 2568: 2544: 2541: 2517: 2497: 2477: 2474: 2464: 2460: 2451:Wolfgang Krull 2446:Krull topology 2432: 2429: 2425: 2421: 2418: 2415: 2412: 2392: 2387: 2383: 2379: 2374: 2370: 2349: 2346: 2342: 2336: 2332: 2328: 2325: 2322: 2319: 2316: 2313: 2309: 2303: 2299: 2295: 2292: 2289: 2279: 2265: 2261: 2257: 2237: 2217: 2214: 2211: 2207: 2203: 2200: 2197: 2194: 2174: 2154: 2130: 2127: 2123: 2119: 2116: 2113: 2110: 2107: 2104: 2080: 2076: 2072: 2053: 2044:and it is the 2033: 2028: 2023: 2001: 1998: 1993: 1988: 1967: 1963: 1959: 1954: 1950: 1946: 1942: 1938: 1933: 1912: 1909: 1906: 1903: 1900: 1897: 1894: 1891: 1888: 1867: 1863: 1859: 1854: 1833: 1829: 1805: 1801: 1783: 1772: 1767: 1762: 1740: 1720: 1717: 1714: 1711: 1690: 1684: 1680: 1675: 1670: 1666: 1662: 1656: 1652: 1647: 1642: 1617: 1596: 1590: 1586: 1581: 1576: 1549: 1544: 1532:-adic integers 1521: 1509: 1500: 1497: 1494: 1480: 1477: 1467: 1457: 1454: 1441: 1421: 1397: 1377: 1373: 1369: 1366: 1361: 1358: 1336: 1321: 1318: 1306: 1303: 1300: 1297: 1294: 1274: 1271: 1265: 1262: 1256: 1253: 1229: 1209: 1206: 1203: 1200: 1197: 1177: 1153: 1130: 1127: 1124: 1121: 1118: 1094: 1074: 1054: 1048: 1045: 1018: 998: 992: 989: 983: 980: 977: 974: 943: 919: 899: 896: 892: 888: 868: 865: 855: 837: 831: 828: 805: 802: 790: 787: 770: 767: 765:construction. 731: 727: 724: 721: 711: 707: 703: 700: 695: 691: 687: 682: 677: 673: 669: 664: 660: 652: 649: 646: 642: 636: 631: 628: 625: 621: 615: 611: 607: 603: 599: 594: 590: 586: 581: 578: 556: 553: 550: 547: 544: 541: 519: 514: 510: 506: 501: 496: 492: 488: 483: 478: 474: 451: 447: 420: 415: 411: 390: 387: 384: 381: 378: 375: 372: 369: 366: 363: 360: 355: 351: 347: 342: 338: 334: 329: 324: 320: 316: 289: 286: 283: 280: 277: 274: 269: 265: 261: 250:indexed family 237: 234: 231: 228: 225: 222: 204:inverse system 191: 188: 183: 180: 149:-adic integers 138: 104:Sylow theorems 87: 66: 62: 59: 26: 18:Krull topology 9: 6: 4: 3: 2: 4572: 4561: 4558: 4556: 4553: 4552: 4550: 4539: 4535: 4531: 4527: 4522: 4517: 4513: 4509: 4508: 4503: 4499: 4496: 4492: 4488: 4486:3-540-61990-9 4482: 4478: 4474: 4470: 4464: 4460: 4456: 4452: 4448: 4442: 4438: 4434: 4430: 4426: 4421: 4416: 4412: 4408: 4407: 4402: 4398: 4394: 4387: 4386: 4381: 4377: 4372: 4367: 4362: 4357: 4353: 4349: 4344: 4339: 4334: 4329: 4324: 4320: 4316: 4311: 4307: 4303: 4299: 4293: 4289: 4285: 4280: 4279: 4271: 4267: 4261: 4253: 4247: 4243: 4239: 4235: 4234: 4226: 4217: 4208: 4199: 4197: 4187: 4179: 4175: 4171: 4167: 4163: 4159: 4154: 4149: 4145: 4141: 4134: 4123: 4119: 4112: 4105: 4103: 4094: 4087: 4080: 4072: 4068: 4064: 4062:9780198500827 4058: 4054: 4047: 4038: 4033: 4026: 4022: 4008: 4005: 3999: 3996: 3994: 3991: 3985: 3983: 3978: 3976: 3973: 3971: 3968: 3967: 3961: 3948: 3940: 3937: 3934: 3924: 3920: 3915: 3887: 3858: 3854: 3833: 3826: 3825:prime numbers 3810: 3788: 3784: 3776: 3773: 3770: 3760: 3757: 3737: 3728: 3715: 3711: 3702: 3699: 3696: 3691: 3687: 3682: 3678: 3672: 3649: 3637: 3628: 3625: 3605: 3602: 3588: 3574: 3560: 3558: 3554: 3550: 3546: 3526: 3519:are free pro- 3506: 3486: 3466: 3458: 3444: 3441: 3438: 3432: 3426: 3423: 3416: 3412: 3411: 3410: 3396: 3387: 3374: 3371: 3365: 3358: 3342: 3336: 3316: 3308: 3298: 3290: 3288: 3284: 3280: 3275: 3273: 3270: 3266: 3250: 3242: 3238: 3234: 3218: 3210: 3200: 3187: 3173: 3151: 3148: 3144: 3123: 3103: 3100: 3080: 3060: 3052: 3037: 3017: 2997: 2977: 2957: 2937: 2931: 2928: 2925: 2915: 2913: 2910: 2906: 2892: 2882: 2878: 2875: 2871: 2867: 2863: 2860: 2856: 2842: 2839: 2832:functions on 2831: 2827: 2826:probabilities 2811: 2808: 2788: 2785: 2777: 2761: 2753: 2750: 2734: 2730: 2726: 2719: 2703: 2700: 2680: 2672: 2668: 2664: 2661: 2657: 2653: 2649: 2648: 2640:is profinite. 2639: 2635: 2632: 2628: 2624: 2620: 2616: 2612: 2609: 2605: 2589: 2569: 2566: 2558: 2542: 2539: 2531: 2530:finite groups 2515: 2495: 2475: 2472: 2462: 2458: 2456: 2452: 2448: 2447: 2427: 2423: 2419: 2413: 2410: 2390: 2385: 2381: 2377: 2372: 2368: 2344: 2340: 2334: 2330: 2323: 2320: 2311: 2307: 2301: 2297: 2290: 2287: 2277: 2263: 2259: 2255: 2235: 2215: 2209: 2205: 2201: 2195: 2192: 2172: 2152: 2144: 2125: 2121: 2117: 2111: 2108: 2105: 2102: 2094: 2078: 2074: 2070: 2062: 2058: 2057:Galois theory 2054: 2051: 2047: 2031: 2026: 1999: 1996: 1986: 1961: 1957: 1940: 1936: 1910: 1907: 1904: 1901: 1898: 1895: 1892: 1889: 1886: 1861: 1857: 1831: 1803: 1788: 1785:The group of 1784: 1770: 1765: 1738: 1718: 1715: 1712: 1709: 1682: 1678: 1673: 1654: 1650: 1645: 1631: 1615: 1588: 1584: 1579: 1565: 1547: 1533: 1519: 1511:The group of 1510: 1507: 1503: 1502: 1496: 1492: 1478: 1475: 1461: 1453: 1439: 1419: 1411: 1395: 1375: 1371: 1367: 1364: 1359: 1356: 1334: 1325: 1317: 1304: 1301: 1298: 1295: 1292: 1272: 1263: 1260: 1254: 1251: 1243: 1227: 1207: 1201: 1198: 1195: 1175: 1167: 1151: 1142: 1128: 1125: 1122: 1119: 1116: 1108: 1092: 1072: 1052: 1046: 1043: 1032: 1016: 996: 990: 987: 978: 975: 972: 963: 961: 957: 941: 933: 917: 897: 894: 890: 886: 866: 863: 849: 835: 829: 826: 803: 800: 786: 784: 780: 776: 766: 764: 760: 756: 751: 749: 746: 729: 725: 722: 719: 709: 705: 701: 693: 689: 680: 675: 671: 667: 662: 658: 650: 647: 644: 634: 629: 626: 623: 613: 609: 601: 597: 592: 588: 584: 579: 576: 554: 551: 548: 545: 542: 539: 517: 512: 508: 504: 499: 494: 490: 486: 481: 476: 472: 449: 445: 436: 418: 413: 409: 385: 382: 379: 376: 373: 370: 367: 364: 361: 358: 353: 349: 340: 336: 332: 327: 322: 318: 307: 306:homomorphisms 303: 287: 281: 278: 275: 272: 267: 263: 251: 235: 229: 226: 223: 213: 209: 205: 201: 200:inverse limit 197: 187: 179: 177: 173: 169: 165: 160: 158: 154: 153:Galois groups 150: 136: 127: 122: 120: 116: 112: 107: 105: 101: 85: 60: 57: 47: 45: 44:finite groups 41: 37: 33: 19: 4511: 4505: 4472: 4432: 4410: 4404: 4384: 4351: 4347: 4318: 4314: 4283: 4270:MathOverflow 4269: 4260: 4232: 4225: 4216: 4207: 4186: 4153:math/0604399 4143: 4139: 4133: 4122:the original 4117: 4092: 4079: 4052: 4046: 4037:math/0703885 4025: 3981: 3729: 3618:that is, if 3566: 3542: 3388: 3296: 3277:By applying 3276: 3233:direct limit 3198: 2776:Haar measure 2718:factor group 2555:This is the 2457:showed that 2444: 2050:finite field 1459: 1326: 1323: 1143: 964: 792: 772: 752: 435:identity map 212:directed set 193: 185: 161: 123: 108: 48: 35: 29: 4393:Oberwolfach 3355:there is a 2610:of a field. 1493:reconstruct 1320:Equivalence 783:Stone space 759:categorical 32:mathematics 4549:Categories 4538:0281.20031 4495:0902.12004 4463:0812.12002 4306:1145.12001 4178:1126.20018 4017:References 3479:the Sylow 3301:projective 3263:is called 3190:structure. 2631:CW complex 1464:surjective 1242:continuous 954:of finite 401:such that 196:isomorphic 182:Definition 115:surjective 3941:∈ 3774:∈ 3767:∏ 3761:≅ 3703:∈ 3688:σ 3676:⟩ 3673:σ 3670:⟨ 3645:¯ 3641:⟩ 3638:σ 3635:⟨ 3603:σ 3591:procyclic 3439:≤ 3427:⁡ 3369:→ 3340:→ 3267:if every 3241:ind-group 3188:algebraic 3174:ι 3149:− 3145:ι 3124:ι 3101:ι 2935:→ 2926:φ 2870:Dan Segal 2830:integrate 2716:then the 2414:⁡ 2378:⊆ 2324:⁡ 2318:→ 2291:⁡ 2196:⁡ 2112:⁡ 1949:→ 1911:… 1804:^ 1713:≥ 1665:→ 1564:procyclic 1491:and then 1365:⁡ 1360:← 1302:η 1270:→ 1264:^ 1205:→ 1152:η 1117:∩ 1073:η 1047:^ 991:^ 982:→ 973:η 830:^ 723:≤ 648:∈ 641:∏ 635:∈ 627:∈ 585:⁡ 580:← 549:≤ 543:≤ 532:whenever 487:∘ 383:≤ 371:∈ 359:∣ 346:→ 279:∈ 230:≤ 61:∈ 4471:(1997), 4431:(1994), 4382:(2003), 4170:15670650 4071:40658188 3964:See also 3539:-groups. 3272:subgroup 3053:Suppose 1499:Examples 745:relative 208:discrete 151:and the 102:and the 4530:2039560 4455:1324577 3357:section 3283:abelian 2652:product 2048:of any 1109:(i.e., 775:compact 433:is the 198:to the 164:compact 4536:  4528:  4493:  4483:  4461:  4453:  4443:  4304:  4294:  4248:  4176:  4168:  4069:  4059:  3803:where 3235:of an 2905:groups 2828:, and 2667:closed 2665:Every 2650:Every 2621:. The 2465:field 2449:after 2278:finite 2228:where 1879:where 1608:where 1388:where 1220:where 910:where 777:, and 202:of an 4526:JSTOR 4389:(PDF) 4356:arXiv 4323:arXiv 4166:S2CID 4148:arXiv 4125:(PDF) 4114:(PDF) 4089:(PDF) 4032:arXiv 3984:group 3547:of a 3116:Then 2874:dense 2859:index 2673:. If 2660:exact 2459:every 2276:is a 2091:is a 1285:with 1031:dense 956:index 757:. In 38:is a 4481:ISBN 4441:ISBN 4292:ISBN 4246:ISBN 4067:OCLC 4057:ISBN 3980:Pro- 3846:and 3555:and 3413:the 3209:dual 3073:and 2970:and 2885:pro- 2868:and 2613:The 2463:some 2055:The 1979:for 1702:for 848:the 166:and 34:, a 4534:Zbl 4516:doi 4491:Zbl 4466:. 4459:Zbl 4415:doi 4366:doi 4352:165 4333:doi 4319:165 4302:Zbl 4238:doi 4174:Zbl 4158:doi 4144:165 3902:or 3587:is 2916:any 2778:on 2625:of 2411:Gal 2321:Gal 2288:Gal 2193:Gal 2145:of 2109:Gal 2059:of 1412:of 1357:lim 1105:is 1033:in 934:in 856:of 577:lim 437:on 248:an 206:of 128:of 30:In 4551:: 4532:, 4524:, 4512:42 4510:, 4489:, 4479:, 4457:, 4451:MR 4449:, 4439:, 4411:38 4409:, 4364:, 4331:, 4300:. 4290:. 4268:. 4244:. 4195:^ 4172:. 4164:. 4156:. 4142:. 4116:. 4101:^ 4091:. 4065:. 3559:. 3424:cd 3289:. 2453:. 785:. 750:. 178:. 159:. 106:. 46:. 4541:. 4518:: 4417:: 4396:. 4375:. 4368:: 4358:: 4342:. 4335:: 4325:: 4308:. 4272:. 4254:. 4240:: 4180:. 4160:: 4150:: 4095:. 4073:. 4040:. 4034:: 3982:p 3949:. 3945:N 3938:n 3935:, 3931:Z 3925:n 3921:p 3916:/ 3911:Z 3888:p 3883:Z 3859:p 3855:G 3834:S 3811:p 3789:p 3785:G 3777:S 3771:p 3758:G 3738:G 3716:. 3712:} 3707:Z 3700:n 3697:: 3692:n 3683:{ 3679:= 3650:, 3629:= 3626:G 3606:; 3575:G 3527:p 3507:G 3487:p 3467:p 3445:; 3442:1 3436:) 3433:G 3430:( 3397:G 3375:. 3372:H 3366:G 3343:G 3337:H 3317:G 3251:G 3219:G 3152:1 3104:. 3081:H 3061:G 3038:G 3018:H 2998:G 2978:H 2958:G 2938:H 2932:G 2929:: 2911:. 2893:p 2861:. 2843:. 2840:G 2812:, 2809:G 2789:, 2786:G 2762:G 2751:. 2735:N 2731:/ 2727:G 2704:, 2701:G 2681:N 2590:K 2570:. 2567:K 2543:. 2540:K 2516:K 2496:K 2476:, 2473:K 2431:) 2428:K 2424:/ 2420:L 2417:( 2391:. 2386:1 2382:F 2373:2 2369:F 2348:) 2345:K 2341:/ 2335:2 2331:F 2327:( 2315:) 2312:K 2308:/ 2302:1 2298:F 2294:( 2264:K 2260:/ 2256:F 2236:F 2216:, 2213:) 2210:K 2206:/ 2202:F 2199:( 2173:K 2153:L 2129:) 2126:K 2122:/ 2118:L 2115:( 2106:= 2103:G 2079:K 2075:/ 2071:L 2052:. 2032:, 2027:p 2022:Z 2000:. 1997:n 1992:| 1987:m 1966:Z 1962:m 1958:/ 1953:Z 1945:Z 1941:n 1937:/ 1932:Z 1908:, 1905:3 1902:, 1899:2 1896:, 1893:1 1890:= 1887:n 1866:Z 1862:n 1858:/ 1853:Z 1832:. 1828:Z 1800:Z 1771:. 1766:p 1761:Z 1739:p 1719:. 1716:m 1710:n 1689:Z 1683:m 1679:p 1674:/ 1669:Z 1661:Z 1655:n 1651:p 1646:/ 1641:Z 1616:n 1595:Z 1589:n 1585:p 1580:/ 1575:Z 1548:p 1543:Z 1520:p 1508:. 1479:, 1476:G 1440:G 1420:G 1396:N 1376:N 1372:/ 1368:G 1335:G 1305:. 1299:g 1296:= 1293:f 1273:H 1261:G 1255:: 1252:g 1228:G 1208:H 1202:G 1199:: 1196:f 1176:H 1129:, 1126:1 1123:= 1120:N 1093:G 1053:. 1044:G 1017:G 997:, 988:G 979:G 976:: 942:G 918:N 898:, 895:N 891:/ 887:G 867:. 864:G 836:, 827:G 804:, 801:G 730:} 726:j 720:i 710:i 706:g 702:= 699:) 694:j 690:g 686:( 681:j 676:i 672:f 668:: 663:i 659:G 651:I 645:i 630:I 624:i 620:) 614:i 610:g 606:( 602:{ 598:= 593:i 589:G 555:. 552:k 546:j 540:i 518:k 513:i 509:f 505:= 500:k 495:j 491:f 482:j 477:i 473:f 450:i 446:G 419:i 414:i 410:f 389:} 386:j 380:i 377:, 374:I 368:j 365:, 362:i 354:i 350:G 341:j 337:G 333:: 328:j 323:i 319:f 315:{ 288:, 285:} 282:I 276:i 273:: 268:i 264:G 260:{ 236:, 233:) 227:, 224:I 221:( 137:p 86:d 65:N 58:d 20:)

Index

Krull topology
mathematics
topological group
finite groups
Lagrange's theorem
Sylow theorems
group homomorphisms
surjective
quotient groups
additive groups
p {\displaystyle p} -adic integers
Galois groups
field extensions
compact
totally disconnected
locally profinite groups
totally disconnected groups
isomorphic
inverse limit
inverse system
discrete
directed set
indexed family
discrete topology
homomorphisms
identity map
relative
product topology
universal property
categorical

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