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Transactions of the American Mathematical Society
ISSN 1088-6850(e) ISSN 0002-9947(p)
     

Compatible valuations and generalized Milnor $ K$-theory

Author(s): Ido Efrat
Journal: Trans. Amer. Math. Soc. 359 (2007), 4695-4709.
MSC (2000): Primary 19F99; Secondary 12J15, 19C99, 12J99
Posted: April 24, 2007
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Abstract: Given a field $ F$ and a subgroup $ S$ of $ F^{\times }$ there is a minimal group $ S\leq H_{S}\leq F^{\times }$ for which there exists an $ S$-compatible valuation whose units are contained in $ H_{S}$. Assuming that $ S$ has finite index in $ F^{\times }$ and contains $ (F^{\times })^{p}$ for $ p$ prime, we describe $ H_{S}$ in computable $ K$-theoretic terms.


References:

[AEJ]
J.K. Arason, R. Elman and B. Jacob, Rigid elements, valuations, and realization of Witt rings, J. Algebra 110 (1987), 449-467.MR 0910395 (89a:11041)

[BaT]
H. Bass and J. Tate, The Milnor ring of a global field, In: Algebraic $ K$-Theory, Part II (H. Bass, ed.), (Battelle Institute Conference 1972; Springer Lect. Notes Math. 342 , 1973, pp. 349-446. MR 0442061 (56:449)

[BK]
E. Becker and E. Köpping, Reduzierte quadratische Formen und Semiordnungen reeller Körper, Abh. Math. Sem. Univ. Hamburg 46 (1977), 143-177.MR 0506028 (58:21934)

[Bo]
N. Bourbaki, Commutative Algebra, Chapters 1-7, Springer, Berlin, 1989.MR 0979760 (90a:13001)

[E1]
I. Efrat, Construction of valuations from $ K$-theory, Math. Res. Letters 6 (1999), 335-344.MR 1713134 (2001i:12011)

[E2]
I. Efrat, The local correspondence over absolute fields - an algebraic approach, Inter. Math. Res. Notices 2000:23 (2000), 1213-1223.MR 1809368 (2002g:12003)

[E3]
I. Efrat, Demuškin fields with valuations, Math. Z. 243 (2003), 333-353.MR 1961869 (2004d:11116)

[E4]
I. Efrat, A generalization of Marshall's equivalence relation, Trans. Amer. Math. Soc. 358 (2006), 2561-2577. MR 2204044

[E5]
I. Efrat, Quotients of Milnor $ K$-rings, orderings, and valuations, Pac. J. Math. 226 (2006), 259-276. MR 2247864

[EF]
I. Efrat and I. Fesenko, Fields Galois-equivalent to a local field of positive characteristic, Math. Res. Letters 6 (1999), 345-356.MR 1713135 (2001i:12004)

[En]
O. Endler, Valuation Theory, Springer, Berlin, 1972. MR 0357379 (50:9847)

[H]
H. Hahn, Über die nichtarchimedischen Grössensysteme, Sitz.-Ber. d. Wiener Akad., Math.-Nat. Klasse, Abt. IIa 116 (1907), 601-653.

[HJ]
Y.S. Hwang and B. Jacob, Brauer group analogues of results relating the Witt ring to valuations and Galois theory, Canad. J. Math. 47 (1995), 527-543.MR 1346152 (97a:12004)

[J]
B. Jacob, On the structure of pythagorean fields, J. Algebra 68 (1981), 247-267.MR 0608534 (82g:12020)

[JWd]
B. Jacob and A. Wadsworth, A new construction of noncrossed product algebras, Trans. Amer. Math. Soc. 293 (1986), 693-722.MR 0816320 (87g:16027)

[Ka]
B. Kahn, La conjecture de Milnor (d'aprés V. Voevodsky), Sém. Bourbaki 1996/97, Astérisque 245 (1997), 379-418.MR 1627119 (2000a:19002)

[Ko]
J. Koenigsmann, From $ p$-rigid elements to valuations (with a Galois-characterisation of $ p$-adic fields), J. reine angew. Math. 465 1995, 165-182.MR 1344135 (96m:12003)

[Kr]
W. Krull, Allgemeine Bewertungstheorie, J. reine angew. Math. 167 (1931), 160-196.

[L]
T.Y. Lam, Orderings, valuations and quadratic forms; Conf. Board of the Mathematical Sciences 52 , AMS, 1983. MR 0714331 (85e:11024)

[Lg]
S. Lang, Algebra, Addison-Wesley Publishing Company, Reading, Massachusetts, 1984.MR 0783636 (86j:00003)

[MS]
A.S. Merkurjev and A.A. Suslin, $ K$-cohomology of Brauer-Severi varieties and the norm residue homomorphism, Math. USSR Izv. 21 (1983), 307-340; English translation (Russian).

[Mi]
J. Milnor, Algebraic $ K$-theory and quadratic forms, Invent. math. 9 (1970), 318-344.MR 0260844 (41:5465)

[NSW]
J. Neukirch, A. Schmidt and K. Wingberg, Cohomology of Number Fields, Springer, Berlin-Heidelberg, 2000. MR 1737196 (2000j:11168)

[R]
P. Ribenboim, Théorie des valuations, Les Presses de l'Université de Montréal, Montréal, 1968. MR 0249425 (40:2670)

[S]
K. Szymiczek, Quadratic forms over fields, Dissertationes Math. (Rosprawy Mat.) 152 (1977).MR 0450199 (56:8495)

[Wd]
A.R. Wadsworth, $ p$-henselian fields: $ K$-theory, Galois cohomology, and graded Witt rings, Pac. J. Math. 105 (1983), 473-496.MR 0691616 (84m:12026)

[Wr1]
R. Ware, Valuation rings and rigid elements in fields, Canad. J. Math. 33 (1981), 1338-1355. MR 0645230 (83i:10028)

[Wr2]
R. Ware, Galois groups of maximal $ p$-extensions, Trans. Amer. Math. Soc. 333 (1992), 721-728. MR 1061780 (92m:12008)

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Additional Information:

Ido Efrat
Affiliation: Department of Mathematics, Ben-Gurion University of the Negev, P.O. Box 653, Be'er-Sheva 84105, Israel
Email: efrat@math.bgu.ac.il

DOI: 10.1090/S0002-9947-07-04132-3
PII: S 0002-9947(07)04132-3
Received by editor(s): March 24, 2005
Posted: April 24, 2007
Additional Notes: This research was supported by the Israel Science Foundation grant No. 8008/02--1
Copyright of article: Copyright 2007, American Mathematical Society


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