1,214 research outputs found
Zappa-Szep products of semigroups and their C*-algebras
No full textZappa-Szep products of semigroups provide a rich class of examples of semigroups that include the self-similar group actions of Nekrashevych. We use Li's construction of semigroups C*-algebras to associate a C*-algebra to Zappa-Szep products and give an explicit presentation of the algebra. We then define a quotient C*-algebra that generalises the Cuntz-Pimsner algebras for self-similar actions. We indicate how knowne examples, previously viewed as distinct classes, fit into our unifying framework. We specifically discuss the Baumslag-Solitar groups, the binary adding machine, the semigroup NXNx, and the ax+b semigroup ZXZx
Zappa-Szép product groupoids and C*-blends
No full textWe study the external and internal Zappa–Szép product of topological groupoids. We show that under natural continuity assumptions the Zappa–Szép product groupoid is étale if and only if the individual groupoids are étale. In our main result we show that the C∗C∗-algebra of a locally compact Hausdorff étale Zappa–Szép product groupoid is a C∗C∗-blend, in the sense of Exel, of the individual groupoid C∗C∗-algebras. We finish with some examples, including groupoids built from ∗∗-commuting endomorphisms, and skew product groupoids
Zappa-Szép product groupoids and C*-blends
No full textWe study the external and internal Zappa-Szép product of topological groupoids.We show that under natural continuity assumptions the Zappa-Szép product groupoid is étale if and only if the individual groupoids are étale. In our main result we show that the C*-algebra of a locally compact Hausdorff étale Zappa-Szép product groupoid is a C*-blend, in the sense of Exel, of the individual groupoid C*-algebras. We finish with some examples, including groupoids built from ⁎-commuting endomorphisms, and skew product groupoids
The Unendorsable Frank Zappa
No full textThe title seems cryptic at first, and the thanks extended to “Jesus Christ—the author of all things good” in the acknowledgments section somewhat puzzling. This collection of essays gathered by Paul Carr offers a comprehensive view of Frank Zappa the artist, the public figure and the man. A prolific performer, composer, producer, recording engineer, social commentator and occasional film director, Frank Zappa never achieved the level of popularity of the major American bands that emerged in t..
Zappa–Szép products of semigroups and their C*-algebras
No full textZappa–Szép products of semigroups provide a rich class of examples of semigroups that include the self-similar group actions of Nekrashevych. We use Li's construction of semigroup C*-algebras to associate a C*-algebra to Zappa–Szép products and give an explicit presentation of the algebra. We then define a quotient C*-algebra that generalises the Cuntz–Pimsner algebras for self-similar actions. We indicate how known examples, previously viewed as distinct classes, fit into our unifying framework. We specifically discuss the Baumslag–Solitar groups, the binary adding machine, the semigroup N⋊N×, and the ax+b-semigroup Z⋊Z×
Zappa-Szep products of semigroups and their C*-algebras
No full textZappa-Szep products of semigroups provide a rich class of examples of semigroups that include the self-similar group actions of Nekrashevych. We use Li's construction of semigroup C*-algebras to associate a C*-algebra to Zappa-Szep products and give an explicit presentation of the algebra. We then define a quotient C*-algebra that generalises the Cuntz-Pimsner algebras for self-similar actions. We indicate how known examples, previously viewed as distinct classes, fit into our unifying framework. We specifically discuss the Baumslag-Solitar groups, the binary adding machine, the semigroup N x N×, and the ax + b-semigroup Z x Z×
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Frank Zappa and Mikhail Bakhtin: Rabelais\u27s carnival made contemporary
No full textFor this project, the author uses Bakhtin\u27s theory of carnival to illuminate Zappa\u27s sound and rhetoric. The author hopes that by using this theoretical lens allows audiences to understand Zappa\u27s choices in subject matter. Those who can see his work as satire and understand the use of carnivalesque techniques in challenging authority see the genius in his work
Development and delivery of a pilot service for the physical infrastructure of metrofood-RI
No full textThe importance of Metrofood Ri for/in the development of the agrofood sector in the South Eastern European (SEE) partner countries
No full textMETROFOOD-RI is a European Research Infrastructure (RI) aiming at promoting metrology in food and nutrition. In the present work, a mapping of existing RIs and networks of the South Eastern European (SEE) METROFOOD partner countries (i.e. FYROM, Greece, Hungary, Republic of Moldova, Romania, Slovenia), related directly or indirectly to the Agrifood sector, is presented and discussed. As reference METROFOOD partner country, The Netherlands is considered. Copyright� (2017) by the International Measurement Confederation (IMEKO). All rights reserved
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