Sofic groups and direct finiteness

We construct an analogue of Neumann's affiliated algebras for sofic group algebras over arbitrary fields. Consequently, we settle Kaplansky's direct finiteness conjecture for sofic groups.Comment: 9 pages, a shortened proof of the main resul

"Co-Operative Identity" - A Theoretical Concept for Dynamic Analysis of Practical Co-Operation: The Dutch Case

The "concept of the co-operative identity" (consisting from the definition, aims and functions of cooperatives and the so-termed co-operative principles) serves as a general theoretical background for the economic analysis of agricultural co-operation. The development of Dutch dairy co-operatives is used as a case study example, which suitably illustrates and represents the processes taking place in the European Union. Some suggestions for further research on the co-operative identity according to each country and different branches and sectors in order to see the substance of co-operation from different economic and non-economic aspects are proposed.agriculture, co-operative, identity, principles, strategy, Agribusiness, Q13, L14, L22,

Integration of small and medium size farmers by co-operatives in the Hungarian fruit and vegetable sector - a case study

The main co-ordinators/channels used in Hungarian fruit and vegetable supply chain are the following: local market, wholesale markets, production co-operatives, marketing cooperatives, producers organisation, processing industry, wholesalers and retailers. Different retail chains gain a progressively larger share of the fresh fruit and vegetable market. It is very important, therefore, that the farmers have to use marketing channels which could give them the strengths (countervailing power) of more concentrated organisations. In this case study, we examine the integration role of Mórakert Purchasing and Service Co-operative, in Mórahalom in county Csongrád which can be found in the southern east part of Hungary. The Morakert co-operative active in the fruit and vegetable sector and it was the first officially acknowledged Producers Organisation (PO) in Hungary. It works as a very successful cooperative (e.g. in terms of increasing annual turnover and membership) thus being a good example for a number of emerging producer organisations.fruit and vegetable, integration, co-operatives, Producers Organisation, Hungary, Agribusiness, Farm Management,

CHANGES IN THE STRUCTURE OF AGRICULTURAL PRODUCTION, FARM STRUCTURE AND INCOME IN HUNGARY IN THE PERIOD OF 2004-2006

This study reviews the major changes in Hungarian agriculture that occurred between 2004 and 2006. Subjects investigated will include the structural shift towards crop production, the drastic decrease in the foreign food trade balance, and agricultures deteriorating capacity to sustain and retain a rural population. (Hereinafter: sustaining and retaining capacity of agriculture). The author will diagnose related problems, but will not offer any solutions. Nevertheless, he will present a perspective stipulating that Hungarian agricultures chronic problems require an agricultural strategy based on political consensus.EU accession, structural change, foreign food trade, sustaining and retaining capacity of agriculture, agricultural strategy, Farm Management,

“Co-operative identityâ€: A theoretical concept for economic analysis of practical co-operation dynamics

Farmers’ problems and co-ordination of agricultural activities cannot be solved simply by EU and/or government support, or by private market co-ordination institutions. Emerging producer groups and co-operatives seem vital in achieving bargaining power. Theoretically, and according to Western European (Dutch, Danish etc.) and US practical experience, one of the major important private institutions that can strengthen producers and help co-ordinate (agricultural) chains is the co-operative entity. To fulfill the basic co-operative aims and to compete in a more market-oriented environment (e.g. more liberal agricultural policies, opening European and world market, etc.) they will initiate new marketing strategies. To implement such new marketing strategies, co-ops have to collect more risk capital and in Western European agricultural co-operatives this is currently precipitating some fundamental financial and organisational changes. To retain the basic co-operative character, they are undertaking internal and external organisational changes, which in a number of cases will create so-called new co-operative structures/models. In this paper the “co-operative identity†concept (meaning the aims and functions of co-operatives, as well as the so-termed co-operative principles) is proposed to serve as a general theoretical background to evaluate economically the flexibility of (agricultural) cooperation. Also proposed is a new, interdisciplinary research focus (including comprehensive theoretical overview). This new focus examines the substance of co-operation and emphasises the importance of combining insights across the social sciences. It uses the results and common findings of economics, law, marketing, financing, organisational studies, management sciences (“hard†sciences), and also some elements of philosophy, psychology, sociology etc. (“soft†disciplines). Also recommended are some suggestions for further comparative research on the “co-operative identityâ€. This is carried out according to each country and different branches and sectors to observe the substance and dynamics of co-operation from different economic and non-economic aspects.Co-operation, co-operative identity, co-operative principles, strategy, marketing, co-ordination, vertical integration, agriculture, Farm Management, Marketing,

String Geometry and the Noncommutative Torus

We construct a new gauge theory on a pair of d-dimensional noncommutative tori. The latter comes from an intimate relationship between the noncommutative geometry associated with a lattice vertex operator algebra A and the noncommutative torus. We show that the (truncated) tachyon subalgebra of A is naturally isomorphic to a class of twisted modules representing quantum deformations of the algebra of functions on the torus. We construct the corresponding even real spectral triples and determine their Morita equivalence classes using string duality arguments. These constructions yield simple proofs of the O(d,d;Z) Morita equivalences between $d$-dimensional noncommutative tori and give a natural physical interpretation of them in terms of the target space duality group of toroidally compactified string theory. We classify the automorphisms of the twisted modules and construct the most general gauge theory which is invariant under the automorphism group. We compute bosonic and fermionic actions associated with these gauge theories and show that they are explicitly duality-symmetric. The duality-invariant gauge theory is manifestly covariant but contains highly non-local interactions. We show that it also admits a new sort of particle-antiparticle duality which enables the construction of instanton field configurations in any dimension. The duality non-symmetric on-shell projection of the field theory is shown to coincide with the standard non-abelian Yang-Mills gauge theory minimally coupled to massive Dirac fermion fields.Comment: 37 pages, LaTeX. Major revisions in section 3. Other minor revisions in the rest of the paper, references adde

Vertical Co-ordanitaion in Transition Agriculture: a Hungarian Cooperative Case Study

The agriculture is traditional risky business, but in transition countries agricultural producers should face some additional difficulties. The agri-food chains are still suffering from underdeveloped market institutions creating severe barriers for price discovery and high transaction costs to co-ordinate market exchanges. Co-operatives are usually neglected as a possible governance structure in recent empirical analyses. This study analyzes the advantages and limitations of cooperatives for establishing an appropriate vertical coordination forms in the framework of transaction cost economics. We present a case study to show that at the recent stage of development in Hungarian agriculture co-operatives can solve some problems arising from missing and embryonic market institutions. We argue that the co-operative is a good example, how an agricultural co-operative can achieve some of the potential advantages, solving many “traditional” TCE and agency problems and serving its members with a continuing growth.