Search results for "ideal"

MR3730338 Reviewed de Jeu, Marcel(NL-LEID-MI); Tomiyama, Jun(J-TOKYM) The closure of ideals of ℓ1(Σ) in its enveloping C∗-algebra. (English summary) …

2018

Given a compact Hausdorff space X and a homeomorphism σ on X, denote by Σ=(X,σ) a topological dynamical system. Then the associated Banach ∗-algebra ℓ1(Σ) is defined as ℓ1(Σ)={a:Z→C(X), ∥a∥:=∑n∈Z∥a(n)∥<∞} with a crossed product–type product (aa′)(n)=∑k∈Za(k)⋅αk(a′(n−k)) and involution a∗(n)=αn(a(−n))¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯, where C(X) denote the space of complex-valued continuous functions on X, and α(f):=f∘σ−1 for f∈C(X). If C∗(Σ) is the enveloping C∗-algebra of ℓ1(Σ), considering a primitive ideal I of ℓ1(Σ), the authors show that there exists a ∗-representation π of ℓ1(Σ) on Hilbert space such that the kernel is I, and that the closure in C∗(Σ) of an ideal of ℓ1(Σ) is an ideal of C∗(Σ).

Economic Logic with Internal Consistency (and Not Only Formal Rigour)

2022

As is well known, during his life Sraffa never published a work explicitly devoted to epistemological issues. This fact should not be interpreted to indicate Sraffa’s lack of interest in such concerns. From Sraffa’s unpublished manuscripts – kept at the Wren Library of Trinity College, Cambridge, and from the books of his personal library – we see that Sraffa had a strong interest in questions of philosophy of 8science (Kurz and Salvadori, 2005). Therefore, a reconstruction of Sraffa’s epistemological theory can only be conjectural and must not leave out of consideration his unpublished manuscripts. In a previous work (Salvadori and Signorino, 2007), we analysed a specific aspect of Sraffa’…

L'evento persona

2018

Il titolo è un monogramma dell’opera: la persona è un evento educativo, la sua ontologia apre il senso originario dell’educare. La Prima parte contiene i Segnavia, saggi di pedagogia fondamentale che elaborano una concezione dell’educazione definita da due istanze: una esistenziale, la realizzazione di una vita piena e totale; l’altra storica, la personalizzazione di un’eredità di senso. La Seconda parte apre Sentieri, attraverso testi di antropologia pedagogica che esplicitano quanto apprendiamo sulla persona nei mondi dell’educazione. Sono dedicati alla famiglia e all’«umanesimo dell’intimità»; all’esperienza di quanti, soprattutto nel volontariato, fanno rientrare nella riuscita della vi…

The associated sheaf functor theorem in algebraic set theory

2008

We prove a version of the associated sheaf functor theorem in Algebraic Set Theory. The proof is established working within a Heyting pretopos equipped with a system of small maps satisfying the axioms originally introduced by Joyal and Moerdijk. This result improves oil the existing developments by avoiding the assumption of additional axioms for small maps and the use of collection sites.

High order accurate shock capturing schemes for two-component Richtmyer-Meshkov instabilities in compressible magnetohydrodynamics

2011

We design a conservative and entropy satisfying numerical scheme to perform numerical simulations of two component Richtmyer-Meshkov (RM) instabilities in compressible magnetohydrodynamics (MHD). We first formulate a conservative model of a two-component compressible MHD fluid ruled under two ideal gases with different adiabatic exponents. The formulation includes a level set function that allows to evolve the two components of the plasma in a conservative and consistent way. We present a set of examples including two-component Riemann problems and high Mach shock wave interactions with entropy contact waves that validate the high order accurate numerical scheme. We observe that turbulent r…

L’algoritmo come strumento didattico in fisica: modellizzazione dei gas ideali classici e quantistici

2011

Viene discussa una procedura per la modellizzazione dei gas ideali quantistici. Inoltre, viene evidenziata l’importanza di supportare le incomplete rappresentazioni mentali degli studenti, in relazione ad argomenti complessi di meccanica statistica e termodinamica, con accurati modelli fisici aventi validità predittiva e fondati sull’ipotesi di possibili meccanismi di funzionamento. L’idea alla base dell’approccio proposto è quella che, in alcuni casi, anche la sola discussione dei risultati di un algoritmo o di un modello può essere sufficiente a migliorare la comprensione di un sistema fisico particolarmente complesso.

Looking at the Nature of Ideas Through New Lenses

2006

What sets humans apart from other animals is not the use of technology: Many mammals are innovative in making simple tools to assist in life. But it is the sheer scale of technological development that distinguishes humans. Over the millennia, people have invented technologies, used them, and enhanced them. The once-innovative technologies become mundane elements of everyday contemporary life as human societies progress. The technological developments of the last decades have dramatically altered most humans’ way of life and perceptions of the myriad elements of the immediate and distant environment. It would not be an exaggeration to view humans as standing at the cusp of profound social c…

Barreras para escapar de la violencia de género: la mirada de las profesionales. Barriers to escape Violence: the professionals' perspective.

2015

This article addresses, from the perspective of social workers, the difficulties faced by battered women and socially excluded who are living in Valencia’s centers for women’s protection. The following information has been gathered with different research techniques, especially through the use of focus groups and interviews. The most important barriers to escape violence described by the interviewees can be classified as external and internal. The former include stunted social and family networks, the lack of economic resources, the existence of children and the absence of institutional resources. In other words, obstacles related to the social structure. The latter refer to the normalizati…

La izquierda pierde por copiar a la derecha. 14 intelectuales europeos explican el hundimiento de la socialdemocracia

2009

Finnish Military Officer Identities and Micro-Political Resistance

2021

Drawing on the concept of micro-political resistance, this article presents an empirical analysis of how officers of the Finnish Defence Forces challenge, resist, and reinforce the collective military identities constructed within the prevailing organizational discourses. There is a need for identity work to meet the norms and ideals of the military, but individuals can also work as change agents. Micro-political resistance derives from feelings of otherness as well as conflict between the dominant organizational identities and individuals’ personal interests. This study presents a thematic discourse analysis based on texts written by 108 officers and 12 interviews on the theme of “the ide…