Eric Christophe Bedos

• Bedos, Eric Christophe & Conti, Roberto (2025). Positive definiteness and Fell bundles over discrete groups. Mathematische Zeitschrift. ISSN 0025-5874. 311. doi: 10.1007/s00209-025-03785-9. Fulltekst i vitenarkiv Vis sammendrag

  Abstract We introduce a natural concept of positive definiteness for bundle maps between Fell bundles over (possibly different) discrete groups and describe several examples. Such maps induce completely positive maps between the associated full cross-sectional C*-algebras in a functorial way. Under the assumption that the kernel of the homomorphism connecting the groups under consideration is amenable, they also induce completely positive maps between the associated reduced cross-sectional C*-algebras. As an application, we define an approximation property for a Fell bundle over a discrete group which generalizes Exel’s approximation property and still implies the weak containment property. Both approximation properties coincide when the unit fibre is nuclear.

• Bedos, Eric Christophe & Conti, Roberto (2024). Heat Properties for Groups. Journal of Fourier Analysis and Applications. ISSN 1069-5869. 30(4). doi: 10.1007/s00041-024-10103-0. Fulltekst i vitenarkiv Vis sammendrag

  We revisit Fourier’s approach to solve the heat equation on the circle in the context of (twisted) reduced group C*-algebras, convergence of Fourier series and semigroups associated to negative definite functions. We introduce some heat properties for countably infinite groups and investigate when they are satisfied. Kazhdan’s property (T) is an obstruction to the weakest property, and our findings leave open the possibility that this might be the only one. On the other hand, many groups with the Haagerup property satisfy the strongest version. We show that this heat property implies that the associated heat problem has a unique solution regardless of the choice of the initial datum.

• Bedos, Eric Christophe & Omland, Tron (2023). C*-irreducibility for reduced twisted group C*-algebras. Journal of Functional Analysis. ISSN 0022-1236. 284(5), s. 109795–109826. doi: 10.1016/j.jfa.2022.109795. Fulltekst i vitenarkiv Vis sammendrag

  We study C*-irreducibility of inclusions of reduced twisted group C*-algebras and of reduced group C*-algebras. We characterize C*-irreducibility in the case of an inclusion arising from a normal subgroup, and exhibit many new examples of C*-irreducible inclusions.

• Bedos, Eric Christophe; Kaliszewski, S.; Quigg, John & Turk, Jonathan (2023). Coactions on C*-algebras and universal properties. Applied Categorical Structures. ISSN 0927-2852. 31(5). doi: 10.1007/s10485-023-09741-0. Fulltekst i vitenarkiv Vis sammendrag

  It is well-known that the maximalization of a coaction of a locally compact group on a C*-algebra enjoys a universal property. We show how this important property can be deduced from a categorical framework by exploiting certain properties of the maximalization functor for coactions. We also provide a dual proof for the universal property of normalization of coactions.

• Bedos, Eric Christophe; Enstad, Ulrik Bo Rufus & Velthoven, Jordy Timo Van (2022). Smooth lattice orbits of nilpotent groups and strict comparison of projections. Journal of Functional Analysis. ISSN 0022-1236. 283(6). doi: 10.1016/j.jfa.2022.109572. Fulltekst i vitenarkiv Vis sammendrag

  This paper provides sufficient density conditions for the existence of smooth vectors generating a frame or Riesz sequence in the lattice orbit of a square-integrable projective representation of a nilpotent Lie group. The conditions involve the product of lattice co-volume and formal dimension, and complement Balian–Low type theorems for the non-existence of smooth frames and Riesz sequences at the critical density. The proof hinges on a connection between smooth lattice orbits and generators for an explicitly constructed finitely generated Hilbert C*-module. An important ingredient in the approach is that twisted group C*-algebras associated to finitely generated nilpotent groups have finite decomposition rank, hence finite nuclear dimension, which allows us to deduce that any matrix algebra over such a simple C*-algebra has strict comparison of projections.

• Bedos, Erik Christopher; Kaliszewski, S. & Quigg, John (2021). Skew products of finitely aligned left cancellative small categories and Cuntz–Krieger algebras. Münster Journal of Mathematics. ISSN 1867-5778. 14, s. 59–99. doi: 10.17879/59019527597. Fulltekst i vitenarkiv Vis sammendrag

  Given a group cocycle on a finitely aligned left cancellative small category (LCSC), we investigate the associated skew product category and its Cuntz–Krieger al- gebra, which we describe as the crossed product of the Cuntz–Krieger algebra of the original category by an induced coaction of the group. We use our results to study Cuntz–Krieger algebras arising from free actions of groups on finitely aligned LCSCs, and to construct coac- tions of groups on Exel–Pardo algebras. Finally, we discuss the universal group of a small category and connectedness of skew product categories.

• Bedos, Erik Christopher & Conti, Roberto (2020). The Fourier-Stieltjes algebra of a C*-dynamical system II. Studia Mathematica. ISSN 0039-3223. 256(2), s. 217–239. doi: 10.4064/sm190826-25-3. Fulltekst i vitenarkiv Vis sammendrag

  We continue our study of the Fourier–Stieltjes algebra associated to a twisted (unital, discrete) C*-dynamical system and discuss how the various notions of equivalence of such systems are reflected at the algebra level. As an application, we show that the amenability of a system, as defined in our previous work, is preserved under Morita equivalence.

• Bédos, Erik & Omland, Tron (2018). On reduced twisted group C*-algebras that are simple and/or have a unique trace. Journal of Noncommutative Geometry. ISSN 1661-6952. 12(3), s. 947–996. doi: 10.4171/JNCG/295. Fulltekst i vitenarkiv Vis sammendrag

  On reduced twisted group C*-algebras that are simple and/or have a unique trace

• Bedos, Erik Christopher; Kaliszewski, Steve; Quigg, John & Spielberg, Jack (2018). On finitely aligned left cancellative categories, Zappa-Szép products and Exel-Pardo algebras. Theory and Applications of Categories. 33(42), s. 1346–1406. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Norling, Magnus Dahler (2017). On Fell bundles over inverse semigroups and their left regular representations. New York journal of mathematics. 23, s. 1013–1044. Fulltekst i vitenarkiv Vis sammendrag

  We prove a version of Wordingham’s theorem for left regular representations in the setting of Fell bundles of inverse semigroups and use this result to discuss the various associated cross sectional C ∗ - algebras. This research was originally published in The New York Journal of Mathematics: http://nyjm.albany.edu/

• Bedos, Erik Christopher & Conti, Roberto (2017). Negative definite functions for C*-dynamical systems. Positivity (Dordrecht). ISSN 1385-1292. 21(4), s. 1625–1646. doi: 10.1007/s11117-017-0490-0. Fulltekst i vitenarkiv Vis sammendrag

  Given an action α of a discrete group G on a unital C∗ -algebra A, we introduce a natural concept of α -negative definiteness for functions from G to A, and examine some of the first consequences of such a notion. In particular, we prove analogs of theorems due to Delorme–Guichardet and Schoenberg in the classical case where A is trivial. We also give a characterization of the Haagerup property for the action α when G is countable.

• Bedos, Erik Christopher; Kaliszewski, S. & Quigg, John (2017). On Exel-Pardo algebras. Journal of operator theory. ISSN 0379-4024. 78(2), s. 309–345. doi: 10.7900/jot.2016aug16.2118. Fulltekst i vitenarkiv Vis sammendrag

  We generalize a recent construction of Exel and Pardo, from discrete groups acting on finite directed graphs to locally compact groups acting on topological graphs. To each cocycle for such an action, we construct a $C^*$-correspondence whose associated Cuntz-Pimsner algebra is the analog of the Exel--Pardo $C^*$-algebra.

• Bedos, Erik Christopher & Conti, Roberto (2016). The Fourier-Stieltjes Algebra of a C*-dynamical system. International Journal of Mathematics. ISSN 0129-167X. 27(6). doi: 10.1142/S0129167X16500506. Fulltekst i vitenarkiv Vis sammendrag

  In analogy with the Fourier–Stieltjes algebra of a group, we associate to a unital discrete twisted C*-dynamical system a Banach algebra whose elements are coefficients of equivariant representations of the system. Building upon our previous work, we show that this Fourier–Stieltjes algebra embeds continuously in the Banach algebra of completely bounded multipliers of the (reduced or full) C*-crossed product of the system. We introduce a notion of positive definiteness and prove a Gelfand–Raikov type theorem allowing us to describe the Fourier–Stieltjes algebra of a system in a more intrinsic way. We also propose a definition of amenability for C*-dynamical systems and show that it implies regularity. After a study of some natural commutative subalgebras, we end with a characterization of the Fourier–Stieltjes algebra involving C*-correspondences over the (reduced or full) C*-crossed product. Read More: http://www.worldscientific.com/doi/10.1142/S0129167X16500506

• Bedos, Erik Christopher & Conti, Roberto (2016). Fourier theory and C*-algebras. Journal of Geometry and Physics. ISSN 0393-0440. 105, s. 2–24. doi: 10.1016/j.geomphys.2016.03.013. Fulltekst i vitenarkiv
• Bédos, Erik & Omland, Tron (2016). On twisted group C∗-algebras associated with FC-hypercentral groups and other related groups. Ergodic Theory and Dynamical Systems. ISSN 0143-3857. 36(6), s. 1743–1756. doi: 10.1017/etds.2015.9. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2015). On maximal ideals in certain reduced twisted C*-crossed products. Mathematical proceedings of the Cambridge Philosophical Society (Print). ISSN 0305-0041. 158(3), s. 399–417. doi: 10.1017/S0305004115000031. Fulltekst i vitenarkiv
• Bedos, Erik Christopher; Kaliszewski, Steve; Quigg, John & Robertson, David (2015). A new look at crossed product correspondences and associated C*-algebras. Journal of Mathematical Analysis and Applications. ISSN 0022-247X. 426(2), s. 1080–1098. doi: 10.1016/j.jmaa.2015.01.055. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2015). Fourier Series and Twisted C*-Crossed Products. Journal of Fourier Analysis and Applications. ISSN 1069-5869. 21(1), s. 32–75. doi: 10.1007/s00041-014-9360-3. Fulltekst i vitenarkiv Vis sammendrag

  This paper is an invitation to Fourier analysis in the context of reduced twisted C*-crossed products associated with discrete unital twisted C*-dynamical systems. We discuss norm-convergence of Fourier series, multipliers and summation processes. Our study relies in an essential way on the (covariant and equivariant) representation theory of C ∗ -dynamical systems on Hilbert C*-modules. It also yields some information on the ideal structure of reduced twisted C*-crossed products.

• Bedos, Erik Christopher & Omland, Tron Ånen (2012). The full group C*-algebra of the modular group is primitive. Proceedings of the American Mathematical Society. ISSN 0002-9939. 140(4), s. 1403–1411. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2012). On discrete twisted C*-dynamical systems, Hilbert C*-modules and regularity. Münster Journal of Mathematics. ISSN 1867-5778. 5, s. 183–208. Fulltekst i vitenarkiv
• Bedos, Erik Christopher; Kaliszewski, Steve & Quigg, John (2011). On reflective-coreflective equivalence and associated pairs. Theory and Applications of Categories. 25, s. 533–536. Fulltekst i vitenarkiv
• Bedos, Erik Christopher; Kaliszewski, Steve & Quigg, John (2011). Reflective-coreflective equivalence. Theory and Applications of Categories. 25, s. 142–179. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Omland, Tron Ånen (2011). Primitivity of some full group C*-algebras. Banach Journal of Mathematical Analysis. ISSN 2662-2033. 5(2), s. 44–58. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2009). On Twisted Fourier Analysis and Convergence of Fourier Series on Discrete Groups. Journal of Fourier Analysis and Applications. ISSN 1069-5869. 15(3), s. 336–365. doi: 10.1007/s00041-009-9067-z. Fulltekst i vitenarkiv
• Tuset, Lars; Bedos, Erik & Conti, Roberto (2005). On amenability and co-amenability of algebraic quantum groups and their corepresentations. Canadian Journal of Mathematics (CJM). ISSN 0008-414X. 57(1), s. 17–61. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2004). On infinite tensor products of projective unitary representations. Rocky Mountain Journal of Mathematics. ISSN 0035-7596. 34(2), s. 467–493. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Tuset, Lars (2003). Amenability and Co-amenability for locally compact quantum groups. International Journal of Mathematics. ISSN 0129-167X. 14(8), s. 865–884. Fulltekst i vitenarkiv Vis sammendrag

  We define concepts of amenability and co-amenability for locally compact quantum groups in the sense of J. Kustermans and S. Vaes. Co-amenability of a lcqg (locally compact quantum group) is proved to be equivalent to a series of statements, all of which imply amenability of the dual lcqg. Further, it is shown that if a lcqg is amenable, then its universal dual lcqg is nuclear. We also define and study amenability and weak containment concepts for representations and corepresentations of lcqg's.

• Tuset, Lars; Bedos, Erik & Murphy, Gerard (2003). amenability and co-amenability of algebraic quantum groups II. Journal of Functional Analysis. ISSN 0022-1236. 201, s. 303–340. Fulltekst i vitenarkiv
• Tuset, Lars & Bedos, Erik (2003). amenability and co-amenability for locally compact groups. International Journal of Mathematics. ISSN 0129-167X. 14(8), s. 865–884. Fulltekst i vitenarkiv
• Tuset, Lars; Bedos, Erik & Murphy, Gerard (2002). amenability and coamenability of algebraic quantum groups. International Journal of Mathematics and Mathematical Sciences. ISSN 0161-1712. 31(10), s. 577–601. Fulltekst i vitenarkiv
• Bedos, Erik Christopher; Murphy, Gerard M. & Tuset, Lars (2001). Co-amenability of compact quantum groups. Journal of Geometry and Physics. ISSN 0393-0440. 40, s. 130–153. Fulltekst i vitenarkiv Vis sammendrag

  We study the concept of co-amenability for a compact quantum group. Several conditions are derived that are shown to be equivalent to it. Some consequences of co-amenability that we obtain are faithfulness of the Haar integral and automatic norm-boundedness of positive linear functionals on the quantum group's Hopf *-algebra (neither of these properties necessarily holds without co-amenability).

• Tuset, Lars; Bedos, Erik & Murphy, Gerard (2001). co-amenability of compact quantum groups. Journal of Geometry and Physics. ISSN 0393-0440. 40, s. 130–153. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Bedos, Eric Christophe (2025). Actions of Fell bundles. doi: https:/sites.google.com/view/2doa-2025/home. Fulltekst i vitenarkiv Vis sammendrag

  In a recent joint work with Roberto Conti, we introduce the concept of (left) action of a Fell bundle (over a discrete group) on a (right) Hilbert bundle (over another Fell bundle). After presenting some examples, we will discuss the connection with the notion of positive definiteness for bundle maps between Fell bundles, and explain how such actions can be used to induce completely positive maps and construct C*-correspondences.

• Bedos, Eric Christophe (2025). On actions of Fell bundles and Herz-Schur multipliers. doi: https:/www.ntnu.edu/imf/sfmnc25. Fulltekst i vitenarkiv Vis sammendrag

  In this talk, we will discuss actions of a Fell bundle B (over a discrete group G) on Hilbert B-bundles and explain how coefficient maps associated to such actions give rise to completely bounded maps on C*(B) and C_r*(B), the full and reduced cross-sectional C*-algebras of B. When B is the group bundle over G, we recover the fact that every function in the Fourier-Stieltjes algebra of G is a Herz-Schur multiplier. The talk will be based on recent joint work with Roberto Conti (Sapienza Univ. of Rome).

• Bedos, Eric Christophe (2024). Differential calculi with quasi-correspondences (after M. Rieffel). Fulltekst i vitenarkiv Vis sammendrag

  Following an article by M. Rieffel on noncommutative resistance networks, we discuss differential calculi with quasi-correspondences. This is useful in connection with quantum metric spaces.

• Bedos, Eric Christophe (2024). Positive definiteness and Fell bundles over discrete groups. Fulltekst i vitenarkiv
• Bedos, Eric Christophe (2024). On index groups for nice error basis. Fulltekst i vitenarkiv
• Bedos, Eric Christophe (2023). On twirling. Fulltekst i vitenarkiv
• Bedos, Eric Christophe (2023). On quantum operations. Fulltekst i vitenarkiv
• Bedos, Eric Christophe (2023). The SIC-problem. Fulltekst i vitenarkiv
• Bedos, Eric Christophe (2023). The Knill-Laflamme conditions: some examples. Fulltekst i vitenarkiv
• Bedos, Eric Christophe (2023). On projective unitary representations of finite groups II. Fulltekst i vitenarkiv
• Bedos, Eric Christophe (2023). On projective unitary representations of finite groups I. Fulltekst i vitenarkiv
• Bedos, Eric Christophe (2023). On projective unitary representations of finite groups III. Fulltekst i vitenarkiv
• Bedos, Eric Christophe & Conti, Roberto (2020). Corrigendum to “Fourier theory and C*-algebras” [J. Geom. Phys. 105 (2016) 2–24]. Journal of Geometry and Physics. ISSN 0393-0440. 150. doi: 10.1016/j.geomphys.2020.103609. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2017). On Exel-Pardo algebras as C*-algebras associated with left cancellative small categories. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2016). Negative definite functions and C*-dynamical systems. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2015). On the Fourier-Stieltjes algebra of a discrete C*-dynamical system. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2014). A review of "Amenable traces and Følner C*-algebras" by Ara, Pere; Lledó, Fernando in Expo. Math. 32 (2014), 161–177. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2014). A review of "Uniqueness of uniform norm and C*-norm in Lp(G,w)" by Akbarbaglu, Ibrahim; Heydarpour, Majid; Maghsoudi, Saeid in Math. Slovaca 64 (2014), 411–422. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2014). On maximal ideals in certain reduced twisted C*-crossed products. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2013). A review of "Property T** for C*-algebras" by Li, Dan, in Acta Math. Sin. (Engl. Ser.) 28 (2012), no. 9, 184–1850. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2013). On ideals of certain reduced crossed products. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2013). A review of "Every topologically amenable locally compact quantum group is amenable" by Zobeidi, Amin in Bull. Aust. Math. Soc. 87 (2013), no. 1, 149–151. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2013). A review of "Classification of inductive limits of outer actions of R on approximate circle algebras" by Dean, Andrew J. in Canad. Math. Bull. 55 (2012), no. 1, 73–80. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2013). On equivariant representations of C*-dynamical systems. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2012). A review of "Phase transition on the Toeplitz algebra of the affine semigroup over the natural numbers" by M. Laca and I. Raeburn in Adv. Math. 225 (2010), no. 2, 643–688. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2012). A review of "Simplicity of C∗-algebras using unique eigenstates" by L.H. Mitchell and W.L. Paschke in J. Operator Theory 64 (2010), no. 2, 321–347. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2012). A review of "Poisson boundaries of discrete quantum groups" by R. Tomatsu in Noncommutative harmonic analysis with applications to probability II, 297–312, Banach Center Publ., 89, Polish Acad. Sci. Inst. Math., Warsaw, 2010. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2011). On Fourier series in reduced crossed products. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2011). A review of "The crossed product von Neumann algebras associated with SL2(R)" by W. Wu, and W. Yuan in Taiwanese J. Math. 14 (2010), no. 4, 1501–1515. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2011). A review of "Independence of group algebras" by R. Conti and J. Hamhalter in Math. Nachr. 283 (2010), no. 6, 818–827. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2011). On regularity of C*-dynamical systems (based on a joint work with R.Conti). Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2011). A review of Projective version of Stinespring type theorems" by T.-L. Costache in Bull. Math. Soc. Sci. Math. Roumanie (N.S.) 53(101) (2010), no. 2, 109–124. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2011). On the regularity of C*-dynamical systems (based on joint work with R. Conti). Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2010). A review of "Continuous and discrete flows on operator algebras" by B. Itzá-Ortiz in J. Aust. Math. Soc. 86 (2009), no. 2, 169–176. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2010). A review of "Proper actions which are not saturated" by D. Marelli and I. Raeburn in Proc. Amer. Math. Soc. 137 (2009), no. 7, 2273–2283. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2009). A review of "Characterizations of compact and discrete quantum groups through second duals" by Volker Runde in J. Operator Theory 60 (2008), no. 2, 415--428. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2009). A review of "A note on the crossed product associated with PSL(2,R)" by WenMing W in. Sci. China Ser. A 51 (2008), no. 11, 2081--2088. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2008). The full group C*-algebra of the modular group is primitive. Fulltekst i vitenarkiv Vis sammendrag

  Presentation of joint work with Tron Å. Omland

• Bedos, Erik Christopher (2007). Om RSA-kryptografi. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2006). Om Google og rangering av web-sider. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2003). Full rulle med sinus og cosinus - et lite Maple-show. Fulltekst i vitenarkiv Vis sammendrag

  En demonstrsjon av hvordan programpakken Maple enkelt kan brukes til å lage illustrajoner av sykloid-kurver og bulkede kuleflater, der funksjonene sinus og cosinus spiller en vesentlig rolle.

• Bedos, Erik Christopher (2002). Om approksimasjon av røtter til polynomer ved hjelp av linær algebra. Fulltekst i vitenarkiv Vis sammendrag

  Populært vitenskapelig foredrag om hvordan moderne programakker i matematikk finner approksimasjon av røttene til et polynom ved hjelp av metoder fra lineær algebra.

• Bedos, Erik Christopher (2002). A review of "Exactness of one relator groups" by Erik Guentner. Mathematical Reviews. ISSN 0025-5629. Fulltekst i vitenarkiv Vis sammendrag

  Dette er en anmeldelse av en artikkel publisert i Proc. Amer. Math. Soc. 130(2002), 1087-1093.

• Bedos, Erik Christopher (2002). Magnetic butterflies. Fulltekst i vitenarkiv Vis sammendrag

  A "magnetic butterfly" is obtained from the spectrum of a discrete magnetic Laplacian by letting one of the component of the magnetic field varies. In the talk , we illustrate two methods for computing approximations of some of these magnetic butterflies associated to discrete magnetic Laplacians on box lattices

• Bedos, Erik Christopher (2001). Amenability and algebraic quantum groups. Fulltekst i vitenarkiv Vis sammendrag

  Foredrag basert på to artikler om dette emnet, skrevet sammen med Gerard M. Murphy og Lars Tuset.

• Bedos, Erik Christopher (2001). Co-amenability and compact quantum groups. Fulltekst i vitenarkiv Vis sammendrag

  Foredrag om en artikkel skrevet sammen med Gerard M. Murphy og Lars Tuset.

• Bedos, Erik Christopher; Kaliszewski, Steve & Quigg, John (2019). Skew products of finitely aligned left cancellative small categories and Cuntz-Krieger algebras. Cornell University Library (arXiv),. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2019). The Fourier-Stieltjes algebra of a C*-dynamical system II. Cornell University Library (arXiv),. Fulltekst i vitenarkiv
• Bedos, Erik Christopher; Kaliszewski, Steven Paul; Quigg, John & Spielberg, Jack (2017). On finitely aligned left cancellative small categories, Zappa-Szep products and Exel-Pardo algebras. Cornell University Library. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Norling, Magnus D. (2016). On Fell bundles over inverse semigroups and their left regular representations. Cornell University Library. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2016). Negative definite functions for C*-dynamical systems. Cornell University Library,. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2015). The Fourier-Stieltjes algebra of a C*-dynamical system. Cornell University Library Ithaca, NY14853, USA. Fulltekst i vitenarkiv
• Bedos, Erik Christopher; Kaliszewski, Steve & Quigg, John (2015). On Exel-Pardo algebras. Cornell University Library Ithaca, NY14853, USA. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Omland, Tron (2014). On twisted group C*-algebras associated with FC-hypercentral groups and other related groups. ArXiV, Cornell University Library, e-print (arXiV: 1410.3017). Fulltekst i vitenarkiv
• Bedos, Erik Christopher; Kaliszewski, Steve; Quigg, John & Robertson, David (2014). A new look at crossed product correspondences and associated C*-algebras. Cornell University Library. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2014). On maximal ideals in certain reduced twisted C*-crossed products. ArXiV, Cornell University Library, e-print (arXiV: 1405.1908). Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2013). Fourier series and twisted C*-crossed products. ArXiV, Cornell University Library, e-print (arXiV: 1303.7381),. Fulltekst i vitenarkiv Vis sammendrag

  This paper is an invitation to Fourier analysis in the context of reduced twisted C*- crossed products associated with discrete unital twisted C*-dynamical systems. We discuss norm-convergence of Fourier series, multipliers and summation processes. Our study relies in an essential way on the (covariant and equivariant) representation the- ory of C∗-dynamical systems on Hilbert C*-modules. It also yields some information on the ideal structure of reduced twisted C*-crossed products.

• Bedos, Erik Christopher (2012). Rom og lineæritet. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag

  Notater i videregående lineær algebra, beregnet for emnet MAT3000/4000 ved UiO, tilgjengelig på emnets hjemmeside.

• Bedos, Erik Christopher & Conti, Roberto (2011). On discrete twisted C*-dynamical systems, Hilbert C*-modules and regularity. ArXiv, Cornell University Library, e-print (arXiv:1104.1731). Fulltekst i vitenarkiv
• Bedos, Eric Christophe & Omland, Tron Ånen (2010). Primitivity of some full group C*-algebras. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag

  We show that the full group C*-algebra of the free product of two nontrivial countable amenable discrete groups, where at least one of them has more than two elements, is primitive. We also show that in many cases, this C*-algebra is antiliminary and has an uncountable family of pairwise inequivalent, faithful irreducible representations.

• Bedos, Eric Christophe & Omland, Tron (2009). The full group C*-algebra of the modular group is primitive. Universitetet i Oslo. Fulltekst i vitenarkiv
• Bedos, Erik Christopher (2007). Om RSA-kryptografi. Universitetet i Oslo. Fulltekst i vitenarkiv
• Bedos, Erik Christopher & Conti, Roberto (2006). Twisted Fourier analysis and convergence of Fourier series on discrete groups. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag

  We study convergence and summation processes of Fourier series in reduced twisted group C*-algebras of discrete groups.

• Bedos, Erik Christopher (2002). Maple-eksempler for MAT120A. Fulltekst i vitenarkiv Vis sammendrag

  Dette er en samling Maple-illustrasjoner laget for kurset MAT120a

• Bedos, Erik Christopher (2001). Maple-eksempler og oppgaver for MAT110a. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag

  Dette er en samling av Maple-illustrasjoner og oppgaver laget for kurset MAT110a.

• Bedos, Erik Christopher; Murphy, Gerard M. & Tuset, Lars (2001). Amenability and co-amenability of algebraic quantum groups II. Universitetet i Oslo. ISSN 9788255313144. Fulltekst i vitenarkiv Vis sammendrag

  We continue our study of the concepts of amenability and co-amenability for algebraic quantum groups in the sense of A. Van Daele and our investigation of their relationship with nuclearity and injectivity. One major tool for our analysis is that every non-degenerate *-representation of the universal C*-algebra associated to an algebraic quantum group has a unitary generator which may be described in a concrete way.

• Bedos, Erik Christopher; Conti, Roberto & Tuset, Lars (2001). On amenability and co-amenability of algebraic quantum groups and their corepresentations. Universitetet i Oslo. ISSN 9788255313182. Fulltekst i vitenarkiv Vis sammendrag

  We introduce and study several amenability properties for unitary corepresentations and *-representations of algebraic quantum groups, which may be used to characterize amenability or co-amenability of such groups. As a background for this study, we also investigate the involved tensor C*-categories.

• Bedos, Erik Christopher; Murphy, Gerard M. & Tuset, Lars (2001). Amenability and co-amenability of algebraic quantum groups. Universitetet i Oslo. ISSN 9788255313137. Fulltekst i vitenarkiv Vis sammendrag

  We define concepts of amenability and co-amenability for algebraic quantum groups in the sense of A.Van Daele. We show that co-amenability of an algebraic quantum group always implies amenability of its dual. Various necessary and/or sufficient conditions for amenability or co-amenability are obtained. Co-amenability is shown to have interesting consequences for the modular theory in the case that the algebraic quantum group is of compact type.

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