% This is MAMATH.DEM, the demonstration file % of the plain TeX macro package from Springer-Verlag % for manuscripta mathematica % version of June 1990 \input mamath.cmm \head{Functional equations for zeta\fonote{$\zeta$ is a Greek letter} functions of non-Gorenstein orders in global fields} \subhead{Functional equations for zeta\fonote{$\zeta$ is a Greek letter} functions\newline of non-Gorenstein orders in global fields} \author{Barry Green\fonote{Financial assistance from the University of Stellenbosch, South Africa, is gratefully acknowledged.}} \authorrunning{Green} \abstract{ This is a small test file for the new Springer-Verlag \TeX-macro support for {\tt manuscripta mathematica}. It is the beginning of an article of Barry W. Green and it is taken out of Vol.\ 64 Fasc.\ 4, 1989. We have modified the text to demonstrate the mamath macro package. } \titlea{1}{Introduction} In 1973 Galkin published a paper [8], which deals with zeta function of a non-maximal order in an algebraic number field or function field in one variable over a finite field of constants. By using the methods of Haar measure and duality he was able to establish a functional equation for non-maximal orders in a closed form involving only zeta functions together with an elementary factor, provided they were Gorenstein. He also gave examples to show that this functional equation does not hold in general in the absence of the Gorenstein condition. In the proof of the functional equation a key role is played by the dualizing module (also called the canonical module by Kunz in [9]) for the order. For Gorenstein orders the dualizing module may be chosen to coincide with the ring and so no distinction between the two is needed. However for non-Gorenstein orders they do not coincide. In this paper we show the zeta function of a non-maximal order may be redefined so that in the absence of the Gorenstein condition one still obtains a functional equation. Recently much work has been done on the zeta and $L$-functions of arithmetic orders, particularly for orders in a finite dimensional semisimple algebra over the rational number field, by Solomon [12], Bushnell and Reiner [5], [6] and [7]. However for non-maximal non-Gorenstein orders in general it appears that little if any work has been done. \titlea{2}{Basic definitions} Throughout the paper $K$ will be either the field of rational numbers $\bbbq$, or a field of rational functions of one-variable over a finite field of constants $F$. Let $O_0$ be either the ring of integers $\bbbz$ or the polynomial ring $F[x]$, respectively. Given $L,M\in {\rm M}(O)$ with $L\subset M,\ [M:L]$ will denote the index of $L$ in $M$. The index is extended to all fractional $O$-ideals by defining $[L:M]=[L:W]/[M:W]$ for any $W\in {\rm M}(O)$ and $W\subset L\cap M$. This definition is independent of the choice of $W$ and one easily sees that $[L:M]=[M:L]^{-1}$ and $[L:M][M:N]=[L:N]$ \definition{}{Let $M\in {\rm M}(O)$ and $s$ be a complex variable. The zeta function of $O$ relative to $M$ is defined as $$ \zeta_O(M,s)=\sum_{\scriptstyle L\in {\rm M}(O)\atop \scriptstyle L\subseteq M}\Vert L\Vert^s_O. $$} For some $r\in E, rM\subseteq O$ and is follows that these zeta functions converge absolutely in the same region as $\zeta_O(s)=\zeta_O(O,s)$, that is for ${\rm Re}(s)>1$. Consequently they are analytic in the half-plane ${\rm Re}(s)>1$. \titled{Euler product identity} Given $M\in {\rm M}(O)$, for each prime ideal $P$ of $O$ we let $\zeta_{O_P}(M_P,s)$ denote the zeta function of the localisation, relative to $M_P$. Then $$ \zeta_O(M,s)=\prod_P\zeta_{O_P}(M_P,s) $$ under the assumption that at least one side of the equation is absolutely convergent. This result is proven by similar method to that of [8], p. 4. See also [5], p. 135 and [12], p. 316. \titlea{3}{Main results} \titled{Local case} Let $O$ be an order in $E$ and $P$ a prime ideal. Then: \theorem{3.1}{For each dualizing $O_P$-module $J_P$, $$ \zeta_{O_P}(J_P,s)/\zeta_{\bar O_P}(s)\in\bbbz[u,u^{-1}] $$ where $u=\Vert P\Vert^s_{O_P}$ and $\bar O_P$ denotes the integral closure of $O_P$ in $E$.\fonote{For the case of the basefield $K=\bbbq$, theorem 3.1 is a special case of Bushnell and Reiner's theorem 1 of [5]}} \remark{}{As a consequence of 3.1 and the result that $\zeta_{\bar O_P}(s)$ admits an analytic continuation to a meromorphic function of the complex plane this is also true of $\zeta_{O_P}(J_P,s)$.} The following theorem shows the way the zeta functions depend on the choice of $J_P$. \theorem{3.2}{Let $J_P$ and $J_{1P}$ be dualizing $O_P$-modules in $E$. Then $$ \zeta_{O_P}(J_P,s)=\Vert(J_P:J_{1P})\Vert^s_{O_P}\zeta_{O_P}(J_{1P},s). $$} \theorem{3.3}{For each dualizing $O_P$-module $J_P,\ \zeta_{O_P}(J_P,s)$ satisfies the functional equation $$ \zeta_{O_P}(J_P,s)/\zeta_{\bar O_P}(s)=\Vert\bar O^*_P\Vert^{2s-1}_{O_P} \zeta_{O_P}(J_P,1-s)/\zeta_{\bar O_P}(1-s) $$ where $\bar O^*_P=(J_P:\bar O_P)$.} \corollary{3.4}{There exists a dualizing $O_P$-modula $J_P$ such that $\bar O^*_P={\cal F}_P$, where ${\cal F}_P$ is the conductor of $\bar O_P$ in $O_P$.} \titleb{3.1}{Basic definitions} The group $SU$(5) -- 5 $\times$ 5 unimodular matrices of determimant 1 -- has $5^2 - 1 = 24$ free entries\dots \theorem{}{The Strong Unconstrained Convex Function\dots} \lemma{3.5}{Let $z\in{\rm ex}_t(F)$ and $\varepsilon>0$. Then there exists a simplex\dots} Consider as an example the following theorem (1.1) (1.6). Several slightly different forms of such theorems can be found in the standard textbooks [1,3]. In general, the theorems show that the causal Cauchy development of a 3-surface is incomplete if \dots \corollary{3.6}{ For any fixed integer $n \ge1,$ there exists\dots} \proposition{3.7}{ For any fixed integer $n \ge1,$ there exists\dots} \proof Since ${\rm ex}_t(F)\subseteq F$, it is trivial that ${\rm hull}_t\bigl ({\rm ex}_t(F)\bigr )\subseteq {\rm hull}_t(F)$\qed \remark{3.8}{All the strict inequalities appearing in the strong versions\dots} \example{3.9}{Let $K\subseteq \bbbr^n$ be a polytope defined as the convex hull of a given finite set\dots } \note{3.10}{Let $K\subseteq \bbbr^n$ be a polytope defined\dots} \definition{3.11}{A convex set K is called circumscribed if\dots} \problem{3.12}{A convex set K is called circumscribed if\dots} \exercise{3.13}{A convex set K is called circumscribed if\dots} \solution{3.14}{A convex set K is called circumscribed if\dots} Somewhat larger masses are possible in particular models. One can, in a general, qualitative way, argue as follows\dots \begfig 2.8 cm {\figure{1.1}{This is the first figure legend in this section}} \endfig {\it [The space for the figure and its legend may appear where it is necessary for the page layout and not where it is coded in the input file.]} These were taken during August 1959 -- December 1976 and at the National Solar Observatory (Kitt Peak) during December 1976 -- July 1984. As the sun rotates, the longitude of the central meridian decreases. \begfig 3 cm \figure{1.2}{This is the legend of a figure. The space for the figure is 3 cm. The legend is longer than one line therefore it is set as a paragraph} \endfig From each daily magnetogram, the magnetic fields around the central meridian have been used to cover all latitudes within this particular longitude band. During the course of one solar rotation, all longitudes get covered, resulting in a synoptic map representing the observed longitudinal (line-of-sight) magnetic field as a function of latitude and longitude. \smallskip \item{a. } Supernovae of Type I (SNI) are believed to occur when a white dwarf, consisting mainly of carbon and oxygen, is accreting matter in a close binary system, and is pushed by the mass transfer beyond the Chandrasekahar limit of stability\dots \item{ b.} The ``double quasar" was discovered in 1979 as a pair of quasars, 6 arcseconds apart, with identical redshifts and spectra. The initial guess that these were two images of one quasar produced by the gravitational lens effect\dots \item{c. } The extragalactic distance scale still depends on the use of standard candles and standard reference distances (such as the distances of the Hyades star cluster)\dots \begref{References} \refno {1.} Diamond, J.: Hypergeometric series with a $p$-adic variable. Pac. J. Math. {\bf 94}, 265-278 (1981) \refno { 2.} Ditters, E.J.: On the classification of smooth commutative formal groups. Higher Hasse-Witt matrices of an Abelian variety in positive characteristic. Journ\'ees de G\'eometrie Alg\'ebrique de Rennes. Ast\'erisque {\bf 63}, 67-72 (1979) \refno {3. } Ditters, E.J.: The formal group of an Abelian variety, defined over $W(k)$. Rapport 144, Vrije Universiteit Amsterdam, October 1980 \refno { 4. }Ditters, E.J.: On the covariant Dieudonn\'e-module of an Abelian variety of dimension two over $W(k)$. Math. Z. {\bf 176}, 135-150 (1981) \refno {5.} Ditters, E.J., Hoving, S.J.: On the connected part of the covariant Tate $p$-divisible group and the $\zeta$-function of the family of hyperelliptic curves $y^2=1+\mu x^N$ modulo various primes. Rapport 355, Vrije Universiteit Amsterdam, December 1987. Math. Z. {\bf 200}, 245-264 (1989) \refno {6.} Dwork, B.: A deformation theory for the zeta function of a hypersurface. Proc. of the International Congress of Mathematicians, pp. 247-259 (1962) \refno {7.} Dwork, B.: Lectures on $p$-adic differential equations. (Grundlehren der math. Wissenschaften, vol. 253) Berlin Heidelberg New York: Springer 1982 \refno {8.} Gross, B.H., Koblitz, N.: Gauss sums and the $p$-adic function. Ann. Math. {\bf 109}, 569-581 (1979) \refno {9.} Hazewinkel, M.: Formal groups and applications. New York: Academic Press 1987 \refno {10.} Honda, T.: On the theory of commutative formal groups. J. Math. Soc. Japan {\bf 22}, 213-246 (1970) \endref \address{Barry W. Green Mathematisches Institut Universit\"at Heidelberg 6900 Heidelberg Federal Republic of Germany} \bye