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163. 30/03/2026 Willian Franca (Federal University of Juiz de Fora, Brazil)
Title: Applications of compact multipliers to algebrability of (l_∞ \ c₀) ∪ {0} and (B(l₂(N)) \ K(l₂(N))) ∪ {0}.
Abstract: In this talk, we deal with the class C = C₁ ∪ C₂, where C₁ (respectively, C₂) is formed by all separable Uniform algebras (respectively, separable commutative C*-algebras) with no compact elements. For a given algebra A in C₁ (respectively, A in C₂), we will show that A is isometrically isomorphic as an algebra (respectively, as a C*-algebra) to a subalgebra M of l_∞ with M ⊂ (l_∞ \ c₀) ∪ {0}. Under the additional assumption that A is non-unital, we verify that there exists a copy of M(A) (the multipliers algebra of A, which is non-separable) inside (l_∞ \ c₀) ∪ {0}. For an infinitely generated abelian C*-algebra B, we will study the least cardinality possible of a system of generators, denoted gen_C(B). In fact, we will deduce that gen_C(B) coincides with the smallest cardinal number n such that an embedding of Δ(B) (the spectrum of B) in Rⁿ exists. The finitely generated version of this result was proved by Nagisa. In addition, we will introduce new concepts of algebrability in terms of gen_C(B)* ((C*)-genalgebrability) and its natural variations. From our methods, we will infer that there is a *-isomorphic copy of l_∞ in (l_∞ \ c₀) ∪ {0}. In particular, (l_∞ \ c₀) ∪ {0} contains a copy of every separable Banach space. Moreover, all the positive answers of this work hold if we replace the set (l_∞ \ c₀) ∪ {0} with (B(l₂(N)) \ K(l₂(N))) ∪ {0}. This is a joint work with Jorge J. Garcés (Universidad Politécnica de Madrid).
Future talks:
164. 06/04/2026 Rong Tang (Jilin University, China)
165. 13/04/2026 Maria Ferrara (Pegaso University, Italy)
166. 20/04/2026 Michael Lau (Laval University, Canada)
167. 27/04/2026 Abdenacer Makhlouf (University of Haute Alsace, France)
168. 04/05/2026 Per Bäck (Mälardalen University, Sweden)
169. 11/05/2026 Krzysztof Radziszewski (University of Białystok, Poland)
170. 18/05/2026 Ágota Figula (University of Debrecen, Hungary)
171. 25/05/2026 Andrés Pérez-Rodríguez (University of Santiago de Compostela, Spain)
172. 01/06/2026 Marco Trombetti (University of Naples Federico II, Italy)
173. 08/06/2026 Ivan Dimitrov (Queen’s University, Canada)
174. 15/06/2026 Rinat Kashaev (University of Geneva, Switzerland)
175. 22/06/2026 María Cueto-Avellaneda (University of Murcia, Spain)
176. 29/06/2026 Michael Kinyon (University of Denver, USA)
177. 06/07/2026 Atabey Kaygun (Istanbul Technical University, Turkey)
178. 13/07/2026 Marco Castelli (University of Salento, Italy)
179. 20/07/2026 Yannic Vargas (CUNEF University, Spain)
180. 27/07/2026 Marijana Butorac (University of Rijeka, Croatia)
181. 03/08/2026 Elad Paran (The Open University of Israel, Israel)
182. 10/08/2026 Diogo Diniz (Federal University of Campina Grande, Brazil)
183. 17/08/2026 Lực Ta (University of Pittsburgh, USA)
184. 24/08/2026 Jethro van Ekeren (Institute of Pure and Applied Mathematics, Brazil)
186. 07/09/2026 Quentin Ehret (New York University Abu Dhabi, United Arab Emirates)
188. 21/09/2026 Geoffrey Powell (University of Angers, France)
190. 05/10/2026 Silvia Properzi (Vrije Universiteit Brussel, Belgium)
191. 12/10/2026 István Heckenberger (Philipps University Marburg, Germany)
195. 09/11/2026 Inna Entova-Aizenbud (Ben Gurion University of the Negev, Israel)
Ivan Kaygorodov • Salvatore Siciliano • Mykola Khrypсhenko • Jobir Adashev