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Dirichlet's unit theorem

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The regulator of an algebraic number field of degree greater than 2 is usually quite cumbersome to calculate, though there are now computer algebra packages that can do it in many cases. It is usually much easier to calculate the product
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consisting of all vectors whose entries have sum 0, and by Dirichlet's unit theorem the image is a lattice in this subspace. The volume of a fundamental domain of this lattice is
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has the property that the sum of any row is zero (because all units have norm 1, and the log of the norm is the sum of the entries in a row). This implies that the absolute value
1243: 818: 1687: 1640: 1574: 1276: 1596: 1335: 967: 945: 583: 542: 511: 413: 268: 1822: 859: 209: 556:, the rank is 1 if it is a real quadratic field, and 0 if an imaginary quadratic field. The theory for real quadratic fields is essentially the theory of 2513: 2383: 707: 2674: 589:
called the regulator. In principle a basis for the units can be effectively computed; in practice the calculations are quite involved when
2433:. Annals of Mathematics Studies. Vol. 74. Princeton, NJ: Princeton University Press and University of Tokyo Press. pp. 36–42. 1299:, and the main difficulty in calculating the class number of an algebraic number field is usually the calculation of the regulator. 17: 2079: 2640: 2598: 2486: 448: 2558: 2438: 2340: 2590: 1449: 366: 316: 1490: 1142:). It measures the "density" of the units: if the regulator is small, this means that there are "lots" of units. 1152: 1455: 43: 864: 2474: 2466: 2332: 322: 1703: 1832: 1289: 1123:
of the determinant of the submatrix formed by deleting one column is independent of the column. The number
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is a finite extension of number fields with degree greater than 1 and the units groups for the integers of
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and imaginary quadratic fields, which have rank 0. The 'size' of the units is measured in general by a
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that plays the same role as the classical regulator does for the group of units, which is a group
1579: 1318: 950: 928: 566: 525: 494: 396: 251: 39: 1989: 1112:{\displaystyle \left(N_{j}\log \left|u_{i}^{(j)}\right|\right)_{i=1,\dots ,r,\;j=1,\dots ,r+1}} 697: 2000:, similar to the classical regulator as a determinant of logarithms of units, attached to any 1966: 838: 2650: 2608: 2496: 2001: 1445: 1296: 2658: 2616: 2568: 2504: 2448: 2350: 1311:
A fundamental domain in logarithmic space of the group of units of the cyclic cubic field
8: 2289: 2184: 2024: 1977: 604:. For a number field with at least one real embedding the torsion must therefore be only 216: 174: 27:
Gives the rank of the group of units in the ring of algebraic integers of a number field
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to 1 or 2 if the corresponding embedding is real or complex respectively. Then the
684: 1879:, is approximately 0.5255. A basis of the group of units modulo roots of unity is 2646: 2604: 2550: 2492: 2478: 2365: 2239: 645:
is a totally complex quadratic extension. The converse holds too. (An example is
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The regulator has the following geometric interpretation. The map taking a unit
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of the algebraic number field (it does not depend on the choice of generators
2668: 2320: 2234: 2188: 755:{\displaystyle \mathbb {Q} \oplus O_{K,S}\otimes _{\mathbb {Z} }\mathbb {Q} } 701: 2020: 1993: 1962: 680: 601: 73: 2549:. Graduate Texts in Mathematics. Vol. 110 (2nd ed.). New York: 586: 212: 31: 2542: 1970: 86:
The statement is that the group of units is finitely generated and has
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The torsion in the group of units is the set of all roots of unity of
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is a positive real number that determines how "dense" the units are.
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and others. Such higher regulators play a role, for example, in the
1961:. A theory of such regulators has been in development, with work of 1937:
A 'higher' regulator refers to a construction for a function on an
90:(maximal number of multiplicatively independent elements) equal to 689: 653:
equal to an imaginary quadratic field; both have unit rank 0.)
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is based on the idea that there will be as many ways to embed
1437:, or of the rational integers, is 1 (as the determinant of a 2514:"The Life and Work of Gustav Lejeune Dirichlet (1805–1859)" 619:
Totally real fields are special with respect to units. If
2623: 2295: 2331:. CRM Monograph Series. Vol. 11. Providence, RI: 1969:, and are expected to occur in evaluations of certain 1648: 1604: 1538: 1493: 1155: 2082: 1835: 1706: 1582: 1532:. This can be seen as follows. A fundamental unit is 1458: 1321: 1251: 1216: 997: 953: 931: 867: 841: 780: 710: 569: 528: 497: 451: 399: 325: 254: 177: 475:{\displaystyle K\otimes _{\mathbb {Q} }\mathbb {R} } 563:The rank is positive for all number fields besides 2219:-adic logarithms of the generators of this group. 2167:via the diagonal embedding of the global units in 2135: 1852: 1816: 1681: 1634: 1590: 1568: 1524: 1479: 1329: 1270: 1237: 1198: 1111: 961: 939: 917: 853: 812: 754: 656:The theorem not only applies to the maximal order 577: 536: 505: 474: 407: 348: 262: 203: 2471:A Course in Computational Algebraic Number Theory 2364:Prasad, Dipendra; Yogonanda, C. S. (2007-02-23). 679:There is a generalisation of the unit theorem by 2666: 383:the number that are complex; in other words, if 2363: 2215:is the determinant of the matrix formed by the 1576:, and its images under the two embeddings into 139:number of conjugate pairs of complex embeddings 2329:-theory, and zeta functions of elliptic curves 820:are a set of generators for the unit group of 2633:Grundlehren der Mathematischen Wissenschaften 2586:Grundlehren der mathematischen Wissenschaften 2627:; Schmidt, Alexander; Wingberg, Kay (2000), 2584: 1976:at integer values of the argument. See also 1525:{\textstyle \log {\frac {{\sqrt {5}}+1}{2}}} 696:, determining the rank of the unit group in 687:) to describe the structure of the group of 612:, having no real embeddings which also have 608:. There are number fields, for example most 2275: 1199:{\textstyle N_{j}\log \left|u^{(j)}\right|} 433:is the number of non-real complex roots of 2635:, vol. 323, Berlin: Springer-Verlag, 2225:states that this determinant is non-zero. 2136:{\displaystyle U_{1}=\prod _{P|p}U_{1,P}.} 2065:denote the subgroup of principal units in 1079: 2366:A Report on Artin's holomorphy conjecture 1837: 1584: 1480:{\displaystyle \mathbb {Q} ({\sqrt {5}})} 1460: 1323: 1219: 955: 933: 748: 741: 712: 571: 530: 499: 468: 461: 401: 333: 256: 194: 2575: 2511: 2381: 2263: 1306: 918:{\displaystyle u^{(1)},\dots ,u^{(r+1)}} 439:(which come in complex conjugate pairs); 2417: 2187:subgroup of the global units, it is an 349:{\displaystyle K=\mathbb {Q} (\alpha )} 14: 2667: 2402: 2465: 2319: 2307: 2296:Neukirch, Schmidt & Wingberg 2000 1853:{\displaystyle \mathbb {Q} (\alpha )} 1375:, then a set of fundamental units is 824:modulo roots of unity. There will be 2541: 2313: 1932: 482:as a product of fields, there being 215:, or pairs of embeddings related by 2675:Theorems in algebraic number theory 2477:. Vol. 138. Berlin, New York: 2007: 616:for the torsion of its unit group. 24: 1983: 1238:{\displaystyle \mathbb {R} ^{r+1}} 925:for the different embeddings into 813:{\displaystyle u_{1},\dots ,u_{r}} 25: 2686: 2408:Neukirch et al. (2008) p. 626–627 1996:to define what is now called the 2034:above some fixed rational prime 765: 700:of rings of integers. Also, the 424:is the number of real roots and 211:; these will either be into the 2154:denote the set of global units 1757: 1682:{\textstyle (-{\sqrt {5}}+1)/2} 2411: 2375: 2357: 2301: 2269: 2257: 2105: 1847: 1841: 1668: 1649: 1635:{\textstyle ({\sqrt {5}}+1)/2} 1621: 1605: 1569:{\textstyle ({\sqrt {5}}+1)/2} 1555: 1539: 1474: 1464: 1271:{\displaystyle R{\sqrt {r+1}}} 1187: 1181: 1040: 1034: 910: 898: 879: 873: 835:, either real or complex. For 343: 337: 198: 184: 44:Peter Gustav Lejeune Dirichlet 13: 1: 2475:Graduate Texts in Mathematics 2459: 2333:American Mathematical Society 2325:Higher regulators, algebraic 389:is the minimal polynomial of 2521:Clay Mathematics Proceedings 1591:{\displaystyle \mathbb {R} } 1330:{\displaystyle \mathbb {Q} } 1295:and the regulator using the 962:{\displaystyle \mathbb {C} } 940:{\displaystyle \mathbb {R} } 578:{\displaystyle \mathbb {Q} } 537:{\displaystyle \mathbb {C} } 506:{\displaystyle \mathbb {R} } 408:{\displaystyle \mathbb {Q} } 263:{\displaystyle \mathbb {Q} } 7: 2629:Cohomology of Number Fields 2228: 1302: 1149:to the vector with entries 649:equal to the rationals and 145:. This characterisation of 10: 2691: 2581:Algebraische Zahlentheorie 2298:, proposition VIII.8.6.11. 2049:denote the local units at 1428:is approximately 0.525455. 610:imaginary quadratic fields 293:Other ways of determining 2589:. Vol. 322. Berlin: 2512:Elstrodt, Jürgen (2007). 1435:imaginary quadratic field 1315:obtained by adjoining to 1210:-dimensional subspace of 126:number of real embeddings 2391:(Thesis). Archived from 2382:Dasgupta, Samit (1999). 2276:Stevenhagen, P. (2012). 2250: 1448:is the logarithm of its 637:have the same rank then 444:tensor product of fields 36:Dirichlet's unit theorem 2547:Algebraic number theory 2245:Shintani's unit theorem 1452:: for example, that of 40:algebraic number theory 18:Regulator (mathematics) 2585: 2137: 1854: 1818: 1817:{\displaystyle \left.} 1683: 1636: 1592: 1570: 1526: 1481: 1429: 1331: 1272: 1239: 1200: 1113: 963: 941: 919: 855: 854:{\displaystyle u\in K} 831:Archimedean places of 814: 774:is a number field and 756: 600:, which form a finite 579: 538: 507: 476: 409: 350: 264: 205: 2222:Leopoldt's conjecture 2138: 1967:Beilinson conjectures 1855: 1826:The regulator of the 1819: 1684: 1637: 1593: 1571: 1527: 1482: 1332: 1310: 1273: 1240: 1201: 1114: 964: 942: 920: 856: 815: 762:has been determined. 757: 580: 539: 508: 477: 410: 351: 265: 206: 38:is a basic result in 2080: 2002:Artin representation 1833: 1704: 1646: 1602: 1580: 1536: 1491: 1456: 1446:real quadratic field 1433:The regulator of an 1319: 1297:class number formula 1249: 1214: 1206:has an image in the 1153: 995: 951: 929: 865: 839: 778: 708: 641:is totally real and 567: 526: 495: 449: 397: 323: 252: 175: 171:field as the degree 46:. It determines the 2385:Stark's Conjectures 1990:Stark's conjectures 1988:The formulation of 1978:Beilinson regulator 1444:The regulator of a 1044: 217:complex conjugation 2133: 2113: 1850: 1828:cyclic cubic field 1814: 1679: 1632: 1588: 1566: 1522: 1477: 1430: 1364:denotes a root of 1327: 1268: 1235: 1196: 1109: 1024: 959: 937: 915: 851: 810: 752: 575: 548:As an example, if 534: 503: 472: 405: 346: 260: 204:{\displaystyle n=} 201: 70:algebraic integers 2642:978-3-540-66671-4 2600:978-3-540-65399-8 2488:978-3-540-55640-4 2419:Iwasawa, Kenkichi 2321:Bloch, Spencer J. 2096: 1933:Higher regulators 1805: 1797: 1785: 1748: 1736: 1660: 1613: 1547: 1520: 1508: 1472: 1266: 663:but to any order 365:is the number of 319:theorem to write 317:primitive element 16:(Redirected from 2682: 2661: 2625:Neukirch, Jürgen 2620: 2588: 2577:Neukirch, Jürgen 2572: 2538: 2536: 2535: 2529: 2523:. Archived from 2518: 2508: 2453: 2452: 2430: 2426: 2415: 2409: 2406: 2400: 2399: 2397: 2390: 2379: 2373: 2372: 2370: 2361: 2355: 2354: 2328: 2317: 2311: 2305: 2299: 2293: 2287: 2286: 2284: 2273: 2267: 2261: 2218: 2212: 2207: 2182: 2170: 2166: 2157: 2153: 2142: 2140: 2139: 2134: 2129: 2128: 2112: 2108: 2092: 2091: 2075: 2064: 2052: 2048: 2037: 2033: 2029: 2018: 2010: 1973: 1960: 1951: 1942: 1927: 1914: 1896: 1878: 1863: 1859: 1857: 1856: 1851: 1840: 1823: 1821: 1820: 1815: 1810: 1806: 1803: 1802: 1798: 1793: 1786: 1781: 1775: 1753: 1749: 1744: 1737: 1732: 1729: 1699: 1688: 1686: 1685: 1680: 1675: 1661: 1656: 1641: 1639: 1638: 1633: 1628: 1614: 1609: 1597: 1595: 1594: 1589: 1587: 1575: 1573: 1572: 1567: 1562: 1548: 1543: 1531: 1529: 1528: 1523: 1521: 1516: 1509: 1504: 1501: 1486: 1484: 1483: 1478: 1473: 1468: 1463: 1450:fundamental unit 1440: 1427: 1423: 1410: 1392: 1374: 1363: 1359: 1336: 1334: 1333: 1328: 1326: 1314: 1294: 1287: 1277: 1275: 1274: 1269: 1267: 1256: 1244: 1242: 1241: 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2479:Springer-Verlag 2462: 2457: 2456: 2441: 2428: 2424: 2416: 2412: 2407: 2403: 2395: 2388: 2380: 2376: 2368: 2362: 2358: 2343: 2326: 2318: 2314: 2306: 2302: 2294: 2290: 2282: 2274: 2270: 2262: 2258: 2253: 2240:Cyclotomic unit 2231: 2216: 2213:-adic regulator 2210: 2205: 2198: 2192: 2181: 2175: 2168: 2165: 2159: 2155: 2152: 2146: 2118: 2114: 2104: 2100: 2087: 2083: 2081: 2078: 2077: 2074: 2066: 2063: 2054: 2050: 2047: 2039: 2035: 2031: 2027: 2016: 2013: 2011:-adic regulator 2008: 1998:Stark regulator 1986: 1984:Stark regulator 1971: 1959: 1953: 1946: 1940: 1935: 1922: 1916: 1904: 1898: 1894: 1887: 1880: 1865: 1861: 1836: 1834: 1831: 1830: 1780: 1776: 1774: 1770: 1731: 1730: 1728: 1724: 1711: 1707: 1705: 1702: 1701: 1690: 1671: 1655: 1647: 1644: 1643: 1624: 1608: 1603: 1600: 1599: 1583: 1581: 1578: 1577: 1558: 1542: 1537: 1534: 1533: 1503: 1502: 1500: 1492: 1489: 1488: 1467: 1459: 1457: 1454: 1453: 1438: 1425: 1418: 1412: 1400: 1394: 1390: 1383: 1376: 1365: 1361: 1338: 1322: 1320: 1317: 1316: 1312: 1305: 1292: 1283: 1255: 1250: 1247: 1246: 1223: 1218: 1217: 1215: 1212: 1211: 1207: 1180: 1176: 1172: 1160: 1156: 1154: 1151: 1150: 1146: 1140: 1132: 1124: 1120: 1054: 1033: 1028: 1020: 1008: 1004: 1003: 999: 998: 996: 993: 992: 981: 978: 970: 954: 952: 949: 948: 932: 930: 927: 926: 897: 893: 872: 868: 866: 863: 862: 840: 837: 836: 825: 804: 800: 785: 781: 779: 776: 775: 768: 747: 740: 739: 735: 723: 719: 711: 709: 706: 705: 690: 674: 664: 661: 657: 650: 646: 642: 638: 634: 630: 620: 613: 605: 597: 590: 570: 568: 565: 564: 558:Pell's equation 554:quadratic field 549: 529: 527: 524: 523: 520: 514: 498: 496: 493: 492: 489: 483: 467: 460: 459: 455: 450: 447: 446: 434: 431: 425: 422: 416: 400: 398: 395: 394: 390: 384: 381: 374: 373:that are real, 370: 363: 357: 332: 324: 321: 320: 309: 303: 300: 294: 287: 281: 277: 271: 255: 253: 250: 249: 248:is Galois over 245: 242: 239: 232: 222: 193: 176: 173: 172: 164: 161: 155: 152: 146: 142: 135: 129: 122: 116: 113: 110: 103: 93: 76: 66: 58: 28: 23: 22: 15: 12: 11: 5: 2688: 2678: 2677: 2663: 2662: 2641: 2621: 2599: 2573: 2559: 2539: 2509: 2487: 2461: 2458: 2455: 2454: 2439: 2410: 2401: 2398:on 2008-05-10. 2374: 2356: 2341: 2312: 2300: 2288: 2268: 2255: 2254: 2252: 2249: 2248: 2247: 2242: 2237: 2230: 2227: 2203: 2196: 2179: 2163: 2150: 2132: 2127: 2124: 2121: 2117: 2111: 2107: 2103: 2099: 2095: 2090: 2086: 2070: 2058: 2043: 2012: 2006: 1985: 1982: 1957: 1934: 1931: 1930: 1929: 1920: 1902: 1892: 1885: 1849: 1846: 1843: 1839: 1824: 1813: 1809: 1801: 1796: 1792: 1789: 1784: 1779: 1773: 1769: 1766: 1763: 1760: 1756: 1752: 1747: 1743: 1740: 1735: 1727: 1723: 1720: 1717: 1714: 1710: 1678: 1674: 1670: 1667: 1664: 1659: 1654: 1651: 1631: 1627: 1623: 1620: 1617: 1612: 1607: 1586: 1565: 1561: 1557: 1554: 1551: 1546: 1541: 1519: 1515: 1512: 1507: 1499: 1496: 1476: 1471: 1466: 1462: 1442: 1416: 1398: 1388: 1381: 1325: 1304: 1301: 1265: 1262: 1259: 1254: 1232: 1229: 1226: 1221: 1194: 1189: 1186: 1183: 1179: 1175: 1171: 1168: 1163: 1159: 1136: 1127:is called the 1106: 1103: 1100: 1097: 1094: 1091: 1088: 1085: 1082: 1078: 1075: 1072: 1069: 1066: 1063: 1060: 1057: 1052: 1047: 1042: 1039: 1036: 1031: 1027: 1023: 1019: 1016: 1011: 1007: 1002: 974: 957: 935: 912: 909: 906: 903: 900: 896: 892: 889: 886: 881: 878: 875: 871: 850: 847: 844: 807: 803: 799: 796: 793: 788: 784: 767: 764: 750: 743: 738: 732: 729: 726: 722: 718: 714: 672: 659: 573: 546: 545: 532: 518: 501: 487: 470: 463: 458: 454: 440: 429: 420: 403: 379: 361: 345: 342: 339: 335: 331: 328: 307: 298: 285: 275: 258: 237: 230: 221: 200: 196: 192: 189: 186: 183: 180: 169:complex number 159: 150: 133: 120: 108: 101: 92: 62: 52:group of units 26: 9: 6: 4: 3: 2: 2687: 2676: 2673: 2672: 2670: 2660: 2656: 2652: 2648: 2644: 2638: 2634: 2630: 2626: 2622: 2618: 2614: 2610: 2606: 2602: 2596: 2592: 2587: 2582: 2578: 2574: 2570: 2566: 2562: 2560:0-387-94225-4 2556: 2552: 2548: 2544: 2540: 2530:on 2021-05-22 2526: 2522: 2515: 2510: 2506: 2502: 2498: 2494: 2490: 2484: 2480: 2476: 2472: 2468: 2464: 2463: 2450: 2446: 2442: 2440:0-691-08112-3 2436: 2432: 2420: 2414: 2405: 2394: 2387: 2386: 2378: 2367: 2360: 2352: 2348: 2344: 2342:0-8218-2114-8 2338: 2334: 2330: 2322: 2316: 2309: 2304: 2297: 2292: 2285:. p. 57. 2281: 2280: 2272: 2265: 2264:Elstrodt 2007 2260: 2256: 2246: 2243: 2241: 2238: 2236: 2235:Elliptic unit 2233: 2232: 2226: 2224: 2223: 2214: 2202: 2195: 2190: 2189:abelian group 2186: 2178: 2172: 2162: 2149: 2143: 2130: 2125: 2122: 2119: 2115: 2109: 2101: 2097: 2093: 2088: 2084: 2073: 2069: 2062: 2057: 2046: 2042: 2026: 2023:and for each 2022: 2005: 2003: 1999: 1995: 1991: 1981: 1979: 1975: 1968: 1964: 1956: 1949: 1944: 1926: 1919: 1912: 1908: 1901: 1891: 1884: 1876: 1872: 1868: 1864:is a root of 1844: 1829: 1825: 1811: 1807: 1799: 1794: 1790: 1787: 1782: 1777: 1771: 1767: 1764: 1761: 1758: 1754: 1750: 1745: 1741: 1738: 1733: 1725: 1721: 1718: 1715: 1712: 1708: 1697: 1693: 1676: 1672: 1665: 1662: 1657: 1652: 1629: 1625: 1618: 1615: 1610: 1563: 1559: 1552: 1549: 1544: 1517: 1513: 1510: 1505: 1497: 1494: 1469: 1451: 1447: 1443: 1441:matrix is 1). 1436: 1432: 1431: 1422: 1415: 1408: 1404: 1397: 1387: 1380: 1372: 1368: 1357: 1353: 1349: 1345: 1341: 1309: 1300: 1298: 1291: 1286: 1279: 1263: 1260: 1257: 1252: 1230: 1227: 1224: 1192: 1184: 1177: 1173: 1169: 1166: 1161: 1157: 1143: 1139: 1135: 1130: 1104: 1101: 1098: 1095: 1092: 1089: 1086: 1083: 1080: 1076: 1073: 1070: 1067: 1064: 1061: 1058: 1055: 1050: 1045: 1037: 1029: 1025: 1021: 1017: 1014: 1009: 1005: 1000: 988: 984: 977: 973: 907: 904: 901: 894: 890: 887: 884: 876: 869: 848: 845: 842: 834: 828: 823: 805: 801: 797: 794: 791: 786: 782: 773: 770:Suppose that 766:The regulator 763: 736: 730: 727: 724: 720: 716: 704:structure of 703: 702:Galois module 699: 698:localizations 695: 694: 686: 682: 677: 671: 667: 654: 627: 623: 617: 611: 603: 594: 588: 561: 559: 555: 517: 486: 456: 452: 445: 441: 437: 428: 419: 387: 378: 368: 360: 340: 329: 326: 318: 314: 313: 312: 306: 297: 291: 284: 274: 244:Note that if 236: 229: 225: 220: 218: 214: 190: 187: 181: 178: 170: 158: 149: 140: 132: 127: 119: 107: 100: 96: 91: 89: 84: 82: 75: 71: 65: 61: 57: 53: 49: 45: 41: 37: 33: 19: 2632: 2628: 2580: 2546: 2532:. Retrieved 2525:the original 2520: 2470: 2467:Cohen, Henri 2423:Lectures on 2422: 2413: 2404: 2393:the original 2384: 2377: 2359: 2324: 2315: 2303: 2291: 2279:Number Rings 2278: 2271: 2259: 2220: 2209: 2200: 2193: 2183:is a finite- 2176: 2173: 2160: 2158:that map to 2147: 2144: 2071: 2067: 2060: 2055: 2044: 2040: 2021:number field 2014: 1997: 1994:Harold Stark 1987: 1963:Armand Borel 1954: 1947: 1936: 1924: 1917: 1910: 1906: 1899: 1889: 1882: 1874: 1870: 1866: 1695: 1691: 1420: 1413: 1406: 1402: 1395: 1385: 1378: 1370: 1366: 1355: 1351: 1347: 1343: 1339: 1290:class number 1284: 1280: 1144: 1137: 1133: 1128: 986: 982: 975: 971: 832: 826: 821: 771: 769: 688: 681:Helmut Hasse 678: 669: 665: 655: 625: 621: 618: 602:cyclic group 595: 562: 547: 515: 484: 435: 426: 417: 385: 376: 358: 304: 295: 292: 282: 272: 270:then either 243: 234: 227: 223: 213:real numbers 156: 147: 138: 130: 125: 117: 114: 105: 98: 94: 85: 80: 74:number field 63: 59: 35: 29: 2543:Lang, Serge 2310:, Table B.4 1945:with index 683:(and later 587:determinant 356:, and then 32:mathematics 2659:0948.11001 2617:0956.11021 2569:0811.11001 2534:2010-06-13 2505:0786.11071 2460:References 2449:0236.12001 2431:-functions 2351:0958.19001 2308:Cohen 1993 1974:-functions 1939:algebraic 1700:matrix is 1337:a root of 593:is large. 522:copies of 491:copies of 442:write the 367:conjugates 219:, so that 2371:(Report). 2145:Then let 2098:∏ 1845:α 1778:− 1768:⁡ 1762:× 1722:⁡ 1716:× 1689:. So the 1653:− 1498:⁡ 1170:⁡ 1129:regulator 1093:… 1068:… 1018:⁡ 888:… 846:∈ 795:… 737:⊗ 717:⊕ 457:⊗ 341:α 81:regulator 2669:Category 2579:(1999). 2545:(1994). 2469:(1993). 2421:(1972). 2323:(2000). 2229:See also 2191:of rank 2053:and let 1860:, where 1393:, where 1303:Examples 969:and set 861:, write 315:use the 2651:1737196 2609:1697859 2497:1228206 1288:of the 415:, then 167:in the 124:is the 54:in the 50:of the 42:due to 2657:  2649:  2639:  2615:  2607:  2597:  2567:  2557:  2503:  2495:  2485:  2447:  2437:  2427:-adic 2349:  2339:  2266:, §8.D 2208:. The 2174:Since 2076:. Set 2038:, let 1950:> 1 1943:-group 1923:= 2 − 1897:where 1804:  1419:= 2 − 991:matrix 693:-units 614:{1,−1} 606:{1,−1} 115:where 79:. The 2528:(PDF) 2517:(PDF) 2396:(PDF) 2389:(PDF) 2369:(PDF) 2283:(PDF) 2251:Notes 2185:index 2025:prime 2019:be a 1439:0 × 0 1360:. If 552:is a 393:over 72:of a 2637:ISBN 2595:ISBN 2555:ISBN 2483:ISBN 2435:ISBN 2337:ISBN 2015:Let 1992:led 1915:and 1698:+ 1) 1642:and 1598:are 1411:and 1346:) = 989:+ 1) 633:and 513:and 311:are 302:and 154:and 137:the 128:and 88:rank 56:ring 48:rank 2655:Zbl 2613:Zbl 2565:Zbl 2501:Zbl 2445:Zbl 2347:Zbl 2206:− 1 2030:of 1913:− 1 1877:− 1 1873:− 2 1765:log 1719:log 1694:× ( 1495:log 1487:is 1409:− 1 1358:− 1 1354:− 2 1167:log 1015:log 985:× ( 947:or 829:+ 1 369:of 288:= 0 280:or 278:= 0 233:+ 2 141:of 111:− 1 68:of 30:In 2671:: 2653:, 2647:MR 2645:, 2631:, 2611:. 2605:MR 2603:. 2593:. 2583:. 2563:. 2553:. 2519:. 2499:. 2493:MR 2491:. 2481:. 2473:. 2443:. 2345:. 2335:. 2199:+ 2171:. 2059:1, 2004:. 1980:. 1909:+ 1905:= 1888:, 1869:+ 1405:+ 1401:= 1384:, 1350:+ 1285:hR 1278:. 676:. 668:⊂ 560:. 427:2r 290:. 226:= 104:+ 97:= 34:, 2619:. 2571:. 2537:. 2507:. 2451:. 2429:L 2425:p 2353:. 2327:K 2217:p 2211:p 2204:2 2201:r 2197:1 2194:r 2180:1 2177:E 2169:E 2164:1 2161:U 2156:ε 2151:1 2148:E 2131:. 2126:P 2123:, 2120:1 2116:U 2110:p 2106:| 2102:P 2094:= 2089:1 2085:U 2072:P 2068:U 2061:P 2056:U 2051:P 2045:P 2041:U 2036:p 2032:K 2028:P 2017:K 2009:p 1972:L 1958:1 1955:K 1948:n 1941:K 1928:. 1925:α 1921:2 1918:ε 1911:α 1907:α 1903:1 1900:ε 1895:} 1893:2 1890:ε 1886:1 1883:ε 1881:{ 1875:x 1871:x 1867:x 1862:α 1848:) 1842:( 1838:Q 1812:. 1808:] 1800:| 1795:2 1791:1 1788:+ 1783:5 1772:| 1759:1 1755:, 1751:| 1746:2 1742:1 1739:+ 1734:5 1726:| 1713:1 1709:[ 1696:r 1692:r 1677:2 1673:/ 1669:) 1666:1 1663:+ 1658:5 1650:( 1630:2 1626:/ 1622:) 1619:1 1616:+ 1611:5 1606:( 1585:R 1564:2 1560:/ 1556:) 1553:1 1550:+ 1545:5 1540:( 1518:2 1514:1 1511:+ 1506:5 1475:) 1470:5 1465:( 1461:Q 1426:K 1421:α 1417:2 1414:ε 1407:α 1403:α 1399:1 1396:ε 1391:} 1389:2 1386:ε 1382:1 1379:ε 1377:{ 1373:) 1371:x 1369:( 1367:f 1362:α 1356:x 1352:x 1348:x 1344:x 1342:( 1340:f 1324:Q 1313:K 1293:h 1264:1 1261:+ 1258:r 1253:R 1231:1 1228:+ 1225:r 1220:R 1208:r 1193:| 1188:) 1185:j 1182:( 1178:u 1174:| 1162:j 1158:N 1147:u 1138:i 1134:u 1125:R 1121:R 1105:1 1102:+ 1099:r 1096:, 1090:, 1087:1 1084:= 1081:j 1077:, 1074:r 1071:, 1065:, 1062:1 1059:= 1056:i 1051:) 1046:| 1041:) 1038:j 1035:( 1030:i 1026:u 1022:| 1010:j 1006:N 1001:( 987:r 983:r 976:j 972:N 956:C 934:R 911:) 908:1 905:+ 902:r 899:( 895:u 891:, 885:, 880:) 877:1 874:( 870:u 849:K 843:u 833:K 827:r 822:K 806:r 802:u 798:, 792:, 787:1 783:u 772:K 749:Q 742:Z 731:S 728:, 725:K 721:O 713:Q 691:S 673:K 670:O 666:O 660:K 658:O 651:L 647:K 643:L 639:K 635:K 631:L 626:K 624:/ 622:L 598:K 591:n 572:Q 550:K 544:. 531:C 519:2 516:r 500:R 488:1 485:r 469:R 462:Q 453:K 436:f 430:2 421:1 418:r 402:Q 391:α 386:f 380:2 377:r 375:2 371:α 362:1 359:r 344:) 338:( 334:Q 330:= 327:K 308:2 305:r 299:1 296:r 286:2 283:r 276:1 273:r 257:Q 246:K 241:. 238:2 235:r 231:1 228:r 224:n 199:] 195:Q 191:: 188:K 185:[ 182:= 179:n 165:K 160:2 157:r 151:1 148:r 143:K 134:2 131:r 121:1 118:r 109:2 106:r 102:1 99:r 95:r 77:K 64:K 60:O 20:)

Index

Regulator (mathematics)
mathematics
algebraic number theory
Peter Gustav Lejeune Dirichlet
rank
group of units
ring
algebraic integers
number field
rank
complex number
real numbers
complex conjugation
primitive element
conjugates
tensor product of fields
quadratic field
Pell's equation
determinant
cyclic group
imaginary quadratic fields
Helmut Hasse
Claude Chevalley
S-units
localizations
Galois module
class number
class number formula

imaginary quadratic field

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