Olimpia Lombardi

En este artículo se argumenta que la existencia de leyes invariantes frente a inversión temporal no es condición indispensable para la existencia de la flecha del tiempo. Esta última puede definirse como una propiedad global y geométrica del espacio-tiempo que no se basa en consideraciones entrópicas ni requiere de la existencia de leyes no invariantes frente a la inversión temporal. A su vez, si el espacio-tiempo cumple ciertas condiciones, la flecha global se traslada a los contextos locales como un flujo tetradimensional de energía que apunta en la misma dirección temporal en todos los puntos espacio-temporales.

In the literature on the interpretation of quantum mechanics, not many works attempt to adopt a proactive perspective aimed at seeing how different interpretations can enrich each other through a productive dialogue. In particular, few proposals have been devised to show that different approaches can be clarified by comparing them, and can even complement each other, improving or leading to a more fertile overall approach. The purpose of this paper is framed within this perspective of complementation and mutual enrichment. In particular, the Relational Quantum Mechanics and the Modal-Hamiltonian Interpretation are compared, highlighting their differences and points of contact. The final purpose is to show that, in spite of their disagreements, they are not contradictory but, on the contrary, they can be made compatible from an overarching perspective and can even complement each other in a fruitful way.

The main aim of this work is to contribute tothe elucidation of the concept of informationby comparing three different views about thismatter: the view of Fred Dretske's semantictheory of information, the perspective adoptedby Peter Kosso in his interaction-informationaccount of scientific observation, and thesyntactic approach of Thomas Cover and JoyThomas. We will see that these views involvevery different concepts of information, eachone useful in its own field of application. This comparison will allow us to argue in favorof a terminological `cleansing': it is necessaryto make a terminological distinction among thedifferent concepts of information, in order toavoid conceptual confusions when the word`information' is used to elucidate relatedconcepts as knowledge, observation orentropy

By moving away from the traditional reductionist reading of the quantum theory of atoms in molecules, in this paper we analyze the role played by QTAIM in the relationship between molecular chemistry and quantum mechanics from an emergentist perspective. In particular, we show that such a relationship involves two steps: an intra-domain emergence and an inter-domain emergence. Intra-domain emergence, internal to quantum mechanics, results from the fact that the electron density, from which all the other QTAIM’s concepts are defined, arises from the wavefunction as a coarse-grained magnitude. Inter-domain emergence involves an analogical link, a mapping, between QTAIM’s entities, such as topological atoms and bond paths, and the entities that populate the molecular-chemistry domain, such as chemical atoms and chemical bonds.

El objetivo del presente artículo es proponer una nueva interpretación del concepto de información en contextos comunicacionales: una interpretación físicocausal. Apelando a las teorías manipulabilistas de la causación, principalmente en su versión intervencionista, buscaremos mostrar que la información comunicacional es una propiedad física que podemos manipular para generar situaciones comunicacionales. Este enfoque nos permite entender la naturaleza de la comunicación como estructura causal, puesta de manifiesto mediante criterios manipulabilistas. Confiamos en que el enfoque propuesto logra superar ciertas dificultades de las interpretaciones de la información actualmente vigentes en la literatura.

In the problem of the relationship between chemistry and physics, many authors take for granted the ontological reduction of the chemical world to the world of physics. The autonomy of chemistry is usually defended on the basis of the failure of epistemological reduction: not all chemical concepts and laws can be derived from the theoretical framework of physics. The main aim of this paper is to argue that this line of argumentation is not strong enough for eliminate the idea of a hierarchical dependence of chemistry with respect to physics. The rejection of the secondary position of chemistry and the defense of the legitimacy of the philosophy of chemistry require a radically different philosophical perspective that denies not only epistemological reduction but also ontological reduction. Only on the basis of a philosophically grounded ontological pluralism it is possible to accept the ontological autonomy of the chemical world and, with this, to reverse the traditional idea of the ‘superiority’ of physics in the context of natural sciences.

In spite of being a well articulated proposal, the theory of quantum histories, in its different versions, suffers from certain difficulties that have been pointed out in the literature. Nevertheless, two facets of the proposal have not been sufficiently stressed. On the one hand, it is a non-collapse formalism that should be technically appropriate to supply descriptions based on quantum properties at different times. On the other hand, it intends to provide an interpretation of quantum mechanics that solves the traditional puzzles of the theory. In this article we spell out the main criticisms to TQH and classify them into two groups: theoretical and interpretive. Whereas the latter might be ignored if the TQH were considered as a quantum formalism with its minimum interpretation, the former seems to point toward technical difficulties that must be faced in a theoretically adequate proposal. Precisely with the purpose of solving these difficulties, we introduce a different perspective, called Formalism of Generalized Contexts or Formalism of Contextual Histories, which supplies a precise condition for consistently talking of quantum properties at different times without the theoretical shortcomings of the TQH.

The core of the environment-induced decoherence program relies on the interaction between the system and its environment; this interaction leads interference to vanish with respect to a definite “preferred basis”. On the other hand, modal interpretations of quantum mechanics supply criteria to select the “preferred context”, where observables acquire definite values. The purpose of this paper is to show the compatibility between the modal interpretative framework and the results of the decoherence program, a compatibility that comes to the light when the Hamiltonian is conceived as the main character of the quantum play

El presente artículo busca ofrecer un análisis conceptual de la noción de información, a partir del modo en que es definida por las teorías formales de Claude Shannon y de Benjamin Schumacher. Contra la postura según la cual existen dos tipos de información de naturalezas diferentes, una información clásica y una información cuántica, aquí argumentamos que no hay razones suficientes para sostener la existencia de la información cuántica como un nuevo tipo sustancialmente distinto de información. Afirmamos así que existe un único tipo de información que puede ser codificado de diversas maneras, en particular, mediante sistemas clásicos o sistemas cuánticos. Esta posición nos conducirá a concebir un concepto unificado y abstracto de información, en un contexto donde la teoría de Shannon resulta neutral e independiente de las teorías físicas utilizadas para describir las partes involucradas en el proceso de transmitir información, y la teoría de Schumacher no define un nuevo tipo de entidad informacional, sino una manera alternativa de codificar la información mediante estados cuánticos. The aim of this article is to offer a conceptual analysis of the notion of information, on the basis of the way in which it is defined by the theories of Claude Shannon and of Benjamin Schumacher. Against the position according to which there are two kinds of information of different natures, a classical information and a quantum information, here we argue that there are not sufficient reasons to maintain the existence of quantum information as a new and substantially different kind of information. So we claim that there is only one kind of information, which can be encoded in different ways, in particular, by means of classical or quantum systems. This position will lead us to conceive an unified and abstract concept of information in a context where Shannon's theory is neutral and independent from the physical theories used to describe the stages involved in the process of transmitting information, and Schumacher's theory does not define a new kind of informational entity, but a alternative way of coding information by means of quantum states

In this work we will deal only with the concept of information in the communicational context, in which information is primarily something that has to be transmitted for communication purposes. The aim of the paper is to consider some arguments traditionally put forward to support the idea that quantum information is qualitatively different than classical information. On the basis of the analysis of those arguments, we will conclude that there are no reasons to admit the existence of quantum information as qualitatively different from classical information: there is only one kind of information, physically neutral, which can be encoded by means of classical or of quantum states.

We propose a new quantum ontology, in which properties are the fundamental building blocks. In this property ontology physical systems are defined as bundles of type-properties. Not all elements of such bundles are associated with definite case-properties, and this accommodates the Kochen and Specker theorem and contextuality. Moreover, we do not attribute an identity to the type-properties, which gives rise to a novel form of the bundle theory. There are no “particles” in the sense of classical individuals in this ontology, although the behavior of such individuals is mimicked in some circumstances. This picture leads in a natural way to the symmetrization postulates for systems of many “identical particles”.

Ilya Prigogine was not a systematic author: his ideas, covering a wide arch of areas, are dispersed in his many writings. In particular, his philosophical thought has to be reconstructed mainly on the basis of his works in collaboration with Isabelle Stengers: La Nouvelle Alliance ( 1979 ), Order out of Chaos ( 1984 ), and Entre le Temps et l’Éternité ( 1988 ). In this paper I undertake that reconstruction in order to argue that Prigogine’s position, when read in the light of Putnam’s internalist realism, can be characterized as an ontological pluralism. The main aim of this work is to show the striking parallelism between the philosophical views of Prigogine and Stengers and those of Hilary Putnam in Reason , Truth and History ( 1981 ). This task will lead me to critically review Prigogine’s general scientific program: the attempt to establish the foundations of objective irreversibility.

El propósito del presente artículo es evaluar en qué sentido y bajo qué condiciones la ergodicidad es relevante para explicar el éxito de la mecánica estadística. Se objeta la positión de quienes sostienen que la ergodicidad es irrelevante para tal explicatión, y se señala que las propiedades ergódicas desempeñan diferentes papeles en la mecánica estadística del equilibrio y en la descriptión de la evolución hacia el equilibrio: es posible prescindir de la ergodicidad en el primer caso pero no en el segundo. Sobre esta base, se reformularán las definiciones de ergodicidad y mezcla, relativizándolas a la macrovariable particular cuya evolución irreversible se desea describir. Finalmente, se enfatiza la importancia de tomar en cuenta la elaboratión de modelos para evaluar la utilizatión de los métodos de Gibbs. /// The aim of this paper is to consider in what sense and under what conditions ergodicity is relevant for explaining the success of Statistical Mechanics. We argue against those who claim that ergodicity is irrelevant to this explanation, by noting that ergodic properties play different roles in equilibrium Statistical Mechanics and in the description of the approach to equilibrium: it is possible to do without it in the first case but not in the second one. On this basis, we reformulate the definitions of ergodicity and mixing, relativizing them to the particular macrovariable whose irreversible evolution is to be described. Finally, we stress the relevance of taking into account model-construction for evaluating the use of Gibbs' methods.

El objetivo del presente trabajo consiste en analizar las diferencias entre los enfoques de Boltzmann y de Gibbs respecto del problema de la irreversibilidad. Dicho análisis nos permitirá poner de manifiesto que, en las discusiones acerca de las condiciones necesarias para la irreversibilidad, no suele advertirse que la diferencia central entre los dos enfoques consiste en la utilización de diferentes conceptos de equilibrio y, por tanto, de irreversibilidad. Finalmente se argumentará que, si bien inicialmente ambos enfoques parecen por completo irreconciliables, existen condiciones físicas definidas bajo las cuales los resultados que proporcionan ambos marcos teóricos se aproximan lo suficiente como para ser considerados igualmente admisibles desde el punto de vista de la práctica de la física.

The many-faced relationship between chemistry and physics is one of the most discussed topics in the philosophy of chemistry. In his recent book Reducing Chemistry to Physics. Limits, Models, Consequences, Hinne Hettema conceives this relationship as a reduction link, and devotes his work to defend this position on the basis of a “naturalized” concept of reduction. In the present paper I critically review three kinds of issues stemming from Hettema’s argumentation: philosophical, scientific and methodological

En este artículo nos proponemos discutir el problema de las relaciones interteóricas desde la perspectiva de un pluralismo ontológico que adopta un realismo de raigambre kantiana. Para ello comenzamos por recordar el concepto tradicional de reducción y sus limitaciones, poniendo el énfasis en los supuestos metafísicos que conlleva tal concepción. A continuación, analizamos otra difundida postura que concibe las relaciones interteóricas en términos de relaciones funcionales, a fin de poner al descubierto ciertas conclusiones inadecuadas que suelen inferirse de tal interpretación. Esta tarea nos conduce a señalar un problema generalmente ignorado en las discusiones sobre el tema, el cual se refiere al modo como se define el sistema bajo estudio. Finalmente, presentamos una caracterización general de nuestro pluralismo ontológico de filiación kantiana, e intentamos poner de manifiesto cómo, en su versión sincrónica, tal pluralismo nos permite afrontar el problema de las relaciones interteóricas de un modo filosóficamente fecundo.