Ordinary Differential Equations

Total Page:16

File Type:pdf, Size:1020Kb

Ordinary Differential Equations THE AMERICAN MATHEMATICAL SOCIETY Edited by John W. Green and Gordon L. Walker CONTENTS MEETINGS Calendar of Meetings • . • • • • • • • • . • • • • • • • • • • • • • • • • • • • . • • 608 The November Meeting in Atlanta, Georgia • • • • . • • • • • • • . • • • • 609 Abstracts of the Meeting - pages 643-650 The November Meeting in Pasadena, California • • • • • . • • • • • . • • • • 613 Abstracts of the Meeting - pages 651-660 The November Meeting in Madison, Wisconsin • • • • • • • . • • • • • • • • 619 Abstracts of the Meeting - pages 661-667 PRELIMINARY ANNOUNCEMENT OF MEETING. • • • • • • . • • • • • • • . • • • • 622 NATIONAL ACADEMY OF SCIENCES - NATIONAL RESEARCH COUNCIL.. • . • 625 NEW NSF POLICIES AND THEIR IMPLEMENTATION. 0 ••• 0 ••••••••• 0 • • • 627 THE VEBLEN PRIZE •.•.•••••.•••••• o o ••• o •••••• 0 • • • • • • • • • • • • 629 NOTES FOR SPEAKERS ••••••.••••..••••••• 0 ••••••••• 0 • • • • • • • • 630 VISITING FOREIGN MATHEMATICIANS • • • • • • . • . • . • • • • • • • • • • • • • • • . 631 NEW AMS PUBLICATIONS •••••.••• 0 • • • • • • • • • • • • • • • • • • • • • • • • • • • 636 PERSONAL ITEMS • • • • • . • • • . • • • • • • • . • . • . • • • . • • • • . • • • • • • • • . • 638 NEWS ITEMS AND ANNOUNCEMENTS •••••••..••.•••••••••••••• QL2,6"18,624 MEMORANDA TO MEMBERS The Employment Register ••••••••••••.•.•.•••. 0 • • • • • • •• 621 Retired Mathematicians • • • • • • • . •••.•••••••••••• 0 • • • • • • 62 9 Sum:mer Employment Opportunities • • . • • • . • • • • • . • • • . • • • . • 642 SUPPLEMENTARY PROGRAM- No. 21 •••••••...••• 0 ••••••••••••••• 641 ABSTRACTS OF CONTRIBUTED PAPERS ••• 0 ••••••• 0 ••••••• 0 ••••• 0 643 INDEX TO ABSTRACTS - Volume 10 •••••••••••••••••••••••••••.. 0 676 INDEX - Volume 10 • • . • • • • • • • • • • • • • • • • • • • • . • . • • • • • • • • • • • • • . • 697 INDEX TO ADVERTISERS •••••••••••••.•.••••.• 0 • • • • • • • • • • • • • •• 703 RESERVATION FORM .•••. 0 ••••••••••••••••••••• 0 •••••••••••• 703 MEETINGS Calendar of Meetings NOTE: This Calendar lists all of the meetings which have been approved by the Council up to the date at which this issue of the NOTICES was sent to press. The summer and annual meetings are joint meetings of the Mathematical Association of America and the American Mathematical Society. The meeting dates which fall rather far in the future are subject to change. This is particularly true of the meetings to which no numbers have yet been assigned. Meet Deadline ing Date Place for No. Abstracts* 608 January 23-27, 1964 (70th Annual Meeting) Miami, Florida Nov. 26 609 February 29, 1964 New York, New York Jan. 16 610 April 18, 1964 Reno, Nevada Mar. 5 611 April 20-23, 1964 New York, New York Mar. 5 612 April 24-25, 1964 Chicago, illinois Mar. 5 613 June 20, 1964 Pullman, Washington May 7 614 August 24-28, 1964 (69th Summer Meeting) Amherst, Massachusetts July 3 January 25-29, 1965 (71st Annual Meeting) Denver, Colorado August 30 - September 3, 1965 (70th Summer Meeting) Ithaca, New York August 1966 (71st Summer Meeting) New Brunswick, New Jersey August, 1967 (72nd Summer Meeting) Toronto, Canada * The abstracts of papers to be presented in person at the meetings must be received in the Head­ quarters Offices of the Society in Providence, Rhode Island, on or before these deadlines. The dead­ lines also apply to news items. The next two deadline dates for by title abstracts are January 9, and February 27, 1964. ------~·~-·~----- The NOTICES of the American Mathematical Society is published by the Society in January, February, April, June, August, October and November. Price per annual volume is $7.00. Price per copy $2.00. Special price for copies sold at registration desks of meetings of the Society, $1,00 per copy. Subscriptions, orders for back numbers (back issues of the last two years only are available) and inquiries should be addressed to the American Mathematical Society, 190 Hope Street, Providence, Rhode Island 02906. Second-class postage paid at Providence, Rhode Island, and additional mailing offices. Authorization is granted under the authority of the act of August 24, 1912, as amended by the act of August 4, 1947 (Sec. 34, 21, P.L. and R.). Accepted for mailing at the special rate of postage provided for in section 34,40, paragraph (d). Copyright© 1963 by the American Mathematical Society Printed in the United States of America Six Hundred Fifth Meeting Georgia Institute of Technology Atlanta, Georgia November 15-16, 1963 PROGRAM The six hundred and fifth meeting ACCOMMODATIONS of the American Mathematical Society will Since there are other meetings and be held at the Georgia Institute of Technol­ conferences in Atlanta at that time, all ogy on Friday and Saturday, November 15 requests for accommodations should be and 16, 1963. The Georgia Institute of Tech­ mailed to: Convention Housing Bureau, nology is at 225 North Avenue in Atlanta, American Mathematical Society, 1102 Georgia. Atlanta is on Eastern Standard Commerce Building, Atlanta, Georgia, Time. 30303. All requests will receive prompt By invitation of the Committee to confirmaton. Following is the list of Select Hour Speakers for Southeastern hotels and motels: Sectional Meetings, Professor Fred B. Wright of the Tulane University of Louisi­ ana will speak on "Invertible elements in Banach Algebras" at 2:00 P.M., Friday, Atlanta Americana November 15. Professor Wright's address Motor Hotel Single $11.00 $14.00 will be in the Auditorium of the A. French Double 14.00 18.00 Textile School. Twin 16.00 20.00 be a session for contrib­ There will Atlanta Cabana afternoon at 3:30 uted papers on Friday Motel Single 11.00 13,00 at P.M. and Saturday morning beginning Double 14.00 16.00 the papers to be 10:00 A.M. Abstracts of Twin 16.00 17.00 presented appear on pages 643-650 of these NOTICES. The titles with corres­ Atlantan Hotel Single 6.00 8.50 ponding numbers are listed in this Pro­ Double 8.50 10.00 gram. Twin 10.00 11.50 Desk will be lo­ The Registration Dinkier Plaza cated in the lower lobby of Price Gilbert Hotel Single 7.00 15.00 Library and will open at 12:30 P.M. Friday. Double 10.00 15.00 Following the sessions there will be Twin 14.00 18.00 a Cocktail Party from 5:00 until 7:00P.M., at the Progressive Club 1050 Techwood Howard Johnson Drive, N. W. A" cash bar" will be operated. Motor Lodge, Single 9.00 12.00 It is recommended that public trans­ N.W. Double 11.00 13.00 portation be used from the hotels to the Twin 12.00 15.00 Georgia Tech campus. Anyone desiring to Peachtree Manor park on the campus should apply ahead of Motel Single 6.00 8.00 time to Professor Bertram M. Drucker, Double 9.00 11.00 Department of Mathematics, Georgia Insti­ Twin 9.00 12,00 tute of Technology, 30332, for a permit to park on the campus. Parking without a Piedmont Hotel Single 6.50 10.50 permit may cause the off-hauling of the Double 10.50 13.50 car. Twin 12.50 16.00 609 TRAVEL Southern, T. W .A., and United Airlines, and Atlanta is served by Delta, Eastern, by the Central of Georgia, Georgia, L and Northwest Orient, Piedmont, Southeastern, N, Seaboard, and Southern Railroads. PROGRAM OF THE SESSIONS The time limit for each contributed paper is ten minutes. The contributed papers are sche­ duled at 15 minute intervals so that the listeners can circulate between the different sessions. To maintain this schedule, the time limit will be strictly enforced. FRIDAY, 2.:00 P.M. Invited Address. Auditorium of the A. French Textile School, Georgia Institute of Tech­ nology Campus Invertible elements in Banach Algebras Professor Fred B. Wright, Tulane University of Louisiana FRIDAY, 3:30 P.M. Session on Analysis and Applied Mathematics, Classroom 2.49, Annex to Library 3:30 - 3:40 (1) Characterization of regular Hausdorff moment sequences Professor J. S. Mac Nerney, University of North Carolina {605-1) 3:45 - 3:55 (2.) Fixed points in gouged convex sets Dr. G. S. Jones, RIAS, Baltimore, Maryland {605-4) 4:00 - 4:10 {3) Uniform bases and the equicontinuity of projections associated with Schauder decompositions Professor C. W. McArthur and Mr. J. R. Retherford*, Florida State Uni­ versity, (605-5) 4:15 - 4:2.5 (4) On the representation of bilinear functionals Professor R. C. Bzoch, Louisiana State University (605-13) 4:30 - 4:40 (5) Some relationships between stability and truncation error for a class of nine­ point analogues of the one-dimensional heat equation Professor J. M. Gwynn, Jr., Georgia Institute of Technology (605-14) FRIDAY, 3:30P.M. Session on Topology and Algebra, Wilby Room 3:30 - 3:40 (6) Representations of a semigroup Mrs. R. S. Cox, University of North Carolina (605-2.) 3:45 - 3:55 (7) Homomorphisms of d-simple inverse semigroups with identity. II Professor R. J. Warne, Virginia Polytechnic Institute (605-3) *For papers with more than one author, an asterisk follows the name of the author who plans to present the paper at the meeting. 610 4:00 - 4:10 (8) Inverse dimension type. I. Types in the real line Professor Jack Segal, Institute for Advanced Study (605-6) 4:15 - 4:25 (9) Upper semi-continuous collections filling up hereditarily indecomposable continua Professor Howard Cook, Auburn University (605-7) 4:30 - 4:40 ( 1 0) Primary ideals and valuation ideals Professor R. W. Gilmer, Jr. *• Florida State University and Professor J. E. Olm, University of Wisconsin (605-8) 4:45 - 4:55 ( 11) A note on torsion-free rings Professor F. L. Hardy, Emory University (605-9) 5:00 - 5:10 (12) Two functions related to the k-free integers Professor Eckford Cohen, University of Tennessee (605-1 0) SATURDAY, 10:00 A.M. Session on Topology and Geometry, Wilby Room 10:00 - 10:10 (13) Idempotents in semigroups on a half-space Professor J. G. Horne, Jr., University of Georgia (605-11) 10:15- 10:25 ( 14) Common fixed points of commuting continuous functions on the unit interval. Preliminary report Professor J. E. Maxfield, and Professor W. J. Howe*, University of Florida (605-12) 10:30 - 10:40 ( 15) On Topological translations in En Professor R. D. Anderson, Louisiana State University (605-15) 10:45 - 10:55 (16) Area in a non-euclidean geometry. Preliminary report Professor R. G. Vinson, Huntington College (605-18) 11:00- 11:10 (17) Slicing a contractible 3-manifold with boundary Dr.
Recommended publications
  • The Center of Topologically Primitive Exponentially Galbed Algebras
    THE CENTER OF TOPOLOGICALLY PRIMITIVE EXPONENTIALLY GALBED ALGEBRAS MART ABEL AND MATI ABEL Received 29 September 2004; Revised 11 December 2005; Accepted 18 December 2005 Let A be a unital sequentially complete topologically primitive exponentially galbed Haus- dorff algebra over C, in which all elements are bounded. It is shown that the center of A is topologically isomorphic to C. Copyright © 2006 Hindawi Publishing Corporation. All rights reserved. 1. Introduction (1) Let A be an associative topological algebra over the field of complex numbers C with separately continuous multiplication. Then A is an exponentially galbed algebra (see, e.g., [1–4, 19, 20]) if every neighbourhood O of zero in A defines another neighbourhood U of zero such that n a k a ... a ∈ U ⊂ O k : 0, , n (1.1) k=0 2 for each n ∈ N. Herewith, A is locally pseudoconvex,ifithasabase{Uλ : λ ∈ Λ} of neigh- bourhoods of zero consisting of balanced and pseudoconvex sets (i.e., of sets U for which μU ⊂ U,whenever|μ| 1, and U + U ⊂ ρU for a ρ 2). In particular, when every Uλ in {Uλ : λ ∈ Λ} is idempotent (i.e., UλUλ ⊂ Uλ), then A is called a locally m-pseudoconvex algebra, and when every Uλ in {Uλ : λ ∈ Λ} is A-pseudoconvex (i.e., for any a ∈ A there is a μ>0suchthataUλ,Uλa ⊂ μUλ), then A is called a locally A-pseudoconvex algebra.Itiswell known (see [21,page4]or[6, page 189]) that the locally pseudoconvex topology on A is given by a family {pλ : λ ∈ Λ} of kλ-homogeneous seminorms, where kλ ∈ (0,1] for each λ ∈ Λ.Thetopologyofalocallym-pseudoconvex (A-pseudoconvex) algebra
    [Show full text]
  • Leavitt Path Algebras
    Gene Abrams, Pere Ara, Mercedes Siles Molina Leavitt path algebras June 14, 2016 Springer vi Preface The great challenge in writing a book about a topic of ongoing mathematical research interest lies in determining who and what. Who are the readers for whom the book is intended? What pieces of the research should be included? The topic of Leavitt path algebras presents both of these challenges, in the extreme. Indeed, much of the beauty inherent in this topic stems from the fact that it may be approached from many different directions, and on many different levels. The topic encompasses classical ring theory at its finest. While at first glance these Leavitt path algebras may seem somewhat exotic, in fact many standard, well-understood algebras arise in this context: matrix rings and Laurent polynomial rings, to name just two. Many of the fundamental, classical ring-theoretic concepts have been and continue to be explored here, including the ideal structure, Z-grading, and structure of finitely generated projective modules, to name just a few. The topic continues a long tradition of associating an algebra with an appropriate combinatorial structure (here, a directed graph), the subsequent goal being to establish relationships between the algebra and the associated structures. In this particular setting, the topic allows for (and is enhanced by) visual, pictorial representation via directed graphs. Many readers are no doubt familiar with the by-now classical way of associating an algebra over a field with a directed graph, the standard path algebra. The construction of the Leavitt path algebra provides another such connection.
    [Show full text]
  • Lifting Defects for Nonstable K 0-Theory of Exchange Rings And
    LIFTING DEFECTS FOR NONSTABLE K0-THEORY OF EXCHANGE RINGS AND C*-ALGEBRAS FRIEDRICH WEHRUNG Abstract. The assignment (nonstable K0-theory), that to a ring R associates the monoid V(R) of Murray-von Neumann equivalence classes of idempotent infinite matrices with only finitely nonzero entries over R, extends naturally to a functor. We prove the following lifting properties of that functor: (i) There is no functor Γ, from simplicial monoids with order-unit with nor- malized positive homomorphisms to exchange rings, such that V ◦ Γ =∼ id. (ii) There is no functor Γ, from simplicial monoids with order-unit with normalized positive embeddings to C*-algebras of real rank 0 (resp., von Neumann regular rings), such that V ◦ Γ =∼ id. 3 (iii) There is a {0, 1} -indexed commutative diagram D~ of simplicial monoids that can be lifted, with respect to the functor V, by exchange rings and by C*-algebras of real rank 1, but not by semiprimitive exchange rings, thus neither by regular rings nor by C*-algebras of real rank 0. By using categorical tools (larders, lifters, CLL) from a recent book from the author with P. Gillibert, we deduce that there exists a unital exchange ring of cardinality ℵ3 (resp., an ℵ3-separable unital C*-algebra of real rank 1) R, with stable rank 1 and index of nilpotence 2, such that V(R) is the positive cone of a dimension group but it is not isomorphic to V(B) for any ring B which is either a C*-algebra of real rank 0 or a regular ring.
    [Show full text]
  • Jacobson Radical and on a Condition for Commutativity of Rings
    IOSR Journal of Mathematics (IOSR-JM) e-ISSN: 2278-5728, p-ISSN: 2319-765X. Volume 11, Issue 4 Ver. III (Jul - Aug. 2015), PP 65-69 www.iosrjournals.org Jacobson Radical and On A Condition for Commutativity of Rings 1 2 Dilruba Akter , Sotrajit kumar Saha 1(Mathematics, International University of Business Agriculture and Technology, Bangladesh) 2(Mathematics, Jahangirnagar University, Bangladesh) Abstract: Some rings have properties that differ radically from usual number theoretic problems. This fact forces to define what is called Radical of a ring. In Radical theory ideas of Homomorphism and the concept of Semi-simple ring is required where Zorn’s Lemma and also ideas of axiom of choice is very important. Jacobson radical of a ring R consists of those elements in R which annihilates all simple right R-module. Radical properties based on the notion of nilpotence do not seem to yield fruitful results for rings without chain condition. It was not until Perlis introduced the notion of quasi-regularity and Jacobson used it in 1945, that significant chainless results were obtained. Keywords: Commutativity, Ideal, Jacobson Radical, Simple ring, Quasi- regular. I. Introduction Firstly, we have described some relevant definitions and Jacobson Radical, Left and Right Jacobson Radical, impact of ideas of Right quasi-regularity from Jacobson Radical etc have been explained with careful attention. Again using the definitions of Right primitive or Left primitive ideals one can find the connection of Jacobson Radical with these concepts. One important property of Jacobson Radical is that any ring 푅 can be embedded in a ring 푆 with unity such that Jacobson Radical of both 푅 and 푆 are same.
    [Show full text]
  • Basically Full Ideals in Local Rings
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE Journal of Algebra 250, 371–396 (2002) provided by Elsevier - Publisher Connector doi:10.1006/jabr.2001.9099, available online at http://www.idealibrary.com on Basically Full Ideals in Local Rings William J. Heinzer Department of Mathematics, Purdue University, West Lafayette, Indiana 47907 and Louis J. Ratliff Jr. and David E. Rush Department of Mathematics, University of California, Riverside, California 92521 Communicated by Craig Huneke Received September 4, 2001 Let A be a finitely generated module over a (Noetherian) local ring R M.We say that a nonzero submodule B of A is basically full in A if no minimal basis for B can be extended to a minimal basis of any submodule of A properly containing B. We prove that a basically full submodule of A is M-primary, and that the fol- lowing properties of a nonzero M-primary submodule B of A are equivalent: (a) B is basically full in A; (b) B =MBA M; (c) MB is the irredundant intersection of µB irreducible ideals; (d) µC≤µB for eachcover C of B. Moreover, if B ∗ is an M-primary submodule of A, then B = MBA M is the smallest basically full submodule of A containing B and B → B∗ is a semiprime operation on the set of nonzero M-primary submodules B of A. We prove that all nonzero M-primary ideals are closed withrespect to thisoperation if and only if M is principal. In rela- tion to the closure operation B → B∗, we define and study the bf-reductions of an M-primary submodule D of A; that is, the M-primary submodules C of D suchthat C ⊆ D ⊆ C∗.IfGM denotes the form ring of R withrespect to M and G+M its maximal homogeneous ideal, we prove that Mn =Mn∗ for all (resp.
    [Show full text]
  • A Prime Ideal Principle in Commutative Algebra
    Journal of Algebra 319 (2008) 3006–3027 www.elsevier.com/locate/jalgebra A Prime Ideal Principle in commutative algebra T.Y. Lam ∗, Manuel L. Reyes Department of Mathematics, University of California, Berkeley, CA 94720, USA Received 11 May 2007 Available online 18 September 2007 Communicated by Luchezar L. Avramov Abstract In this paper, we offer a general Prime Ideal Principle for proving that certain ideals in a commutative ring are prime. This leads to a direct and uniform treatment of a number of standard results on prime ideals in commutative algebra, due to Krull, Cohen, Kaplansky, Herstein, Isaacs, McAdam, D.D. Anderson, and others. More significantly, the simple nature of this Prime Ideal Principle enables us to generate a large number of hitherto unknown results of the “maximal implies prime” variety. The key notions used in our uniform approach to such prime ideal problems are those of Oka families and Ako families of ideals in a commutative ring, defined in (2.1) and (2.2). Much of this work has also natural interpretations in terms of categories of cyclic modules. © 2007 Elsevier Inc. All rights reserved. Keywords: Commutative algebra; Commutative rings; Prime ideals; Ideal families; Prime ideal principles; Module categories 1. Introduction One of the most basic results in commutative algebra, given as the first theorem in Kaplansky’s book [Ka2], is (1.1) below, which guarantees that certain kinds of ideals in a commutative ring are prime. (In the following, all rings are assumed to be commutative with unity, unless otherwise specified.) * Corresponding author. E-mail addresses: [email protected] (T.Y.
    [Show full text]
  • The Jacobson Radical of Commutative Semigroup Rings
    JOURNAL OF ALGEBRA 150, 378-387 (1992) The Jacobson Radical of Commutative Semigroup Rings A. V. KELAREV Department of Mathematics, Ural State Unirersity, Lenina 51, Ekatherhtburg, 620083 Russia Communicated by T. E. llall Received January 26, 1990 In this paper we consider semiprimitive commutative semigroup rings and related matters. A ring is said to be semiprhnitive if the Jacobson radical of it is equal to zero. This property is one of the most important in the theory of semigroup rings, and there is a prolific literature pertaining to the field (see 1,,14]). All semiprimitive rings are contained in another interesting class of rings. Let 8 denote the class of rings R such that ~/(R) = B(R), where J and B are the Jacobson and Baer radicals. Clearly, every semiprimitive ring is in 6". This class, appears, for example, in the theory of Pl-rings and in com- mutative algebra. (In particular, every finitely generated PI-ring and every Hilbert ring are in 6".) Therefore, it is of an independent interest. Meanwhile it is all the more interesting because any characterization of the semigroup rings in 6" will immediately give us a description of semi- primitive semigroup rings. Indeed, a ring R is semiprimitive if and only if R~6" and R is semiprime, i.e., B(R)=O. Semiprime commutative semi- group rings have been described by Parker and Giimer 1,12] and, in other terms, by Munn [9]. So it suffices to characterize semigroup rings in 6". Semigroup rings of 6" were considered by Karpilovsky r5], Munn 1,6-9], Okninski 1-10-h and others.
    [Show full text]
  • ON REDUCED MODULES and RINGS Mangesh B. Rege and A. M. Buhphang 1. INTRODUCTION a Ring Is Reduced If It Has No Nonzero Nilpotent
    International Electronic Journal of Algebra Volume 3 (2008) 58-74 ON REDUCED MODULES AND RINGS Mangesh B. Rege and A. M. Buhphang Received: 20 March 2007; Revised: 11 December 2007 Communicated by Abdullah Harmancı Abstract. In this paper we extend several results known for reduced rings to reduced modules. We prove that for a semiprime module or a module with zero Jacobson radical, the concepts of reduced, symmetric, ps-Armendariz and ZI modules coincide. New examples of reduced modules are furnished: flat mod- ules over reduced rings and modules with zero Jacobson radical over left quo rings are reduced. Rings over which all modules are reduced/symmetric are characterized. Mathematics Subject Classification (2000): 16S36, 16D80 Keywords: reduced modules, semiprime modules, ZI modules, ps-Armendariz modules 1. INTRODUCTION A ring is reduced if it has no nonzero nilpotent elements. Reduced rings have been studied for over forty years ( see [19] ), and the reduced ring Rred = R=Nil(R) associated with a commutative ring R has been of interest to commutative alge- braists. Recently the reduced ring concept was extended to modules by Lee and Zhou in [15] and the relationship of reduced modules with ( what we call as ) ZI modules was studied by Baser and Agayev in [5]. In this paper we extend several results involving reduced rings and related rings to modules. All our rings are associative with identity, subrings and ring homomorphisms are unitary and - unless otherwise mentioned - modules are unitary left modules. Domains need not be commutative. R denotes a ring and M denotes an R-module. Module homomorphisms are written on the side opposite that of scalars.
    [Show full text]
  • Arxiv:1507.04134V1 [Math.RA]
    NILPOTENT, ALGEBRAIC AND QUASI-REGULAR ELEMENTS IN RINGS AND ALGEBRAS NIK STOPAR Abstract. We prove that an integral Jacobson radical ring is always nil, which extends a well known result from algebras over fields to rings. As a consequence we show that if every element x of a ring R is a zero of some polynomial px with integer coefficients, such that px(1) = 1, then R is a nil ring. With these results we are able to give new characterizations of the upper nilradical of a ring and a new class of rings that satisfy the K¨othe conjecture, namely the integral rings. Key Words: π-algebraic element, nil ring, integral ring, quasi-regular element, Jacobson radical, upper nilradical 2010 Mathematics Subject Classification: 16N40, 16N20, 16U99 1. Introduction Let R be an associative ring or algebra. Every nilpotent element of R is quasi-regular and algebraic. In addition the quasi-inverse of a nilpotent element is a polynomial in this element. In the first part of this paper we will be interested in the connections between these three notions; nilpo- tency, algebraicity, and quasi-regularity. In particular we will investigate how close are algebraic elements to being nilpotent and how close are quasi- regular elements to being nilpotent. We are motivated by the following two questions: Q1. Algebraic rings and algebras are usually thought of as nice and well arXiv:1507.04134v1 [math.RA] 15 Jul 2015 behaved. For example an algebraic algebra over a field, which has no zero divisors, is a division algebra. On the other hand nil rings and algebras, which are of course algebraic, are bad and hard to deal with.
    [Show full text]
  • Exchange Rings and Their Extensions
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Journal of Pure and Applied Algebra 179 (2003) 117–126 www.elsevier.com/locate/jpaa Exchange rings and their extensions Chan Yong Honga;∗ , NamKyun Kim b , Yang Leec aDepartment of Mathematics and Research Institute for Basic Sciences Kyung Hee University, Seoul 130-701, South Korea bDivision of General Education, Hanbat National University, Daejeon 305-719, South Korea cDepartment of Mathematics, Pusan National University, Pusan 609-735, South Korea Received 29 September 2001; received in revised form 9 July 2002 Communicated by M.-F. Roy Abstract A ring R is called to be exchange if the right regular module RR has ÿnite exchange property. We continue in this paper the study of exchange rings by several authors. In particular, we investigate the von Neumann regularity of exchange rings. In addition, we also study whether the exchange property is inherited by some extensions of exchange rings. c 2003 Elsevier Science B.V. All rights reserved. MSC: 16E50; 16L30 0. Introduction Throughout this paper, all rings are associative with identity and all modules are unitary. Given a ring R, J(R) denotes the Jacobson radical of R. Let MR be a right R-module. Following Crawley and JÃonsson [6], MR is said to have the exchange prop- erty if for every module A and any two decompositions of A R R AR = MR ⊕ NR = Ai i∈I with M ∼= M , there exist submodules A ⊆ A such that R R i i AR = MR ⊕ Ai : i∈I ∗ Corresponding author.
    [Show full text]
  • Regular Ideals in Commutative Rings, Sublattices of Regular Ideals, and Prtifer Rings
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector JOURNAL OF ALGEBRA 111, 404426 (1987) Regular Ideals in Commutative Rings, Sublattices of Regular Ideals, and Prtifer Rings D. D. ANDERSON* AND J. PASCUAL+ Departmenr of Muthematics, The University qf Iowa, Iowa City, Iowa 52242 Communicated by J. DieudonnC Received April 9, 1986 In this paper we investigate regularly generated. regular, semiregular, and faithful ideals in a commutative ring R and the sublattices they determine. Connections with multiplicative lattice theory are given. Given a Priifer ring R we show that there is a Priifer domain D with the sublattice of regular ideals of R isomorphic to the lattice of ideals of D. Numerous examples of rings with zero divisors having cer- tain properties are given. A Priifer ring with an invertible ideal that is not generated by regular elements is constructed. An example is given to show that the intersec- tion of two regular principal ideals need not be generated by regular elements. (I3 1987 Academic Press. lnc 1. INTRODUCTION Throughout this paper, R will be a commutative ring with identity. We are interested in how parts of the multiplicative theory of ideals for integral domains extend to rings with zero divisors; in particular, to what extent the regular ideals of a ring R behave like the ideals of an integral domain. Section 2 contains the necessary definitions and some preliminary remarks. Regularly generated, regular, semiregular, and faithful ideals are defined along with several “regularity” conditions for rings. A brief outline of the method of idealization is given.
    [Show full text]
  • Idempotent Pairs and PRINC Domains
    Idempotent pairs and PRINC domains Giulio Peruginelli, Luigi Salce and Paolo Zanardo∗ August 28, 2018 Dedicated to Franz Halter-Koch on the occasion of his 70th birthday Abstract A pair of elements a,b in an integral domain R is an idempotent pair if either a(1 a) bR, − ∈ or b(1 b) aR. R is said to be a PRINC domain if all the ideals generated by an idempotent − ∈ pair are principal. We show that in an order R of a Dedekind domain every regular prime ideal can be generated by an idempotent pair; moreover, if R is PRINC, then its integral closure, which is a Dedekind domain, is PRINC, too. Hence, a Dedekind domain is PRINC if and only if it is a PID. Furthermore, we show that the only imaginary quadratic orders Z[√ d], d > 0 − square-free, that are PRINC and not integrally closed, are for d = 3, 7. Keywords: Orders, Conductor, Primary decomposition, Dedekind domains, Principal ideals, Projective- free. 2010 Mathematics Subject Classification: 13G05, 13F05, 13C10, 11R11. Introduction. Let R be an integral domain, Mn(R) the ring of matrices of order n with entries in R, T any singular matrix in Mn(R) (i.e. det T = 0). A natural question is to find conditions on R to ensure that T is always a product of idempotent matrices. This problem was much investigated in past years, see [17] for comprehensive references. The case when R is a B´ezout domain (i.e. the finitely generated ideals of R are all principal) is crucial. In fact, we recall three fundamental results, valid for matrices with entries in a B´ezout domain.
    [Show full text]