A partir del examen de la noción de dialéctica ofrecida por Jean-Paul Sartre en “Cuestiones de método”, se identifican tres características propias de dicha noción presentes en la dialéctica de Hegel: el papel de la reflexión, la negatividad y la relación entre la dialéctica y la subjetividad.

In the paper, the idea of describing not-yet-verified (i.e., pre-existing) properties of quantum objects with logical many-valuedness is scrutinized. As it is argued, to promote such an idea one must first decide how to deal with bivalence of the everyday macrophysical experience in many-valued semantics and, correspondingly, clear up the tradeoff between logical 2-valuedness and many-valuedness. The conceptual difficulties accompanying a two-valued reduction of many-valued logics are discussed.

The global energy system is undergoing a major transition, and in energy planning and decision-making across governments, industry and academia, models play a crucial role. Because of their policy relevance and contested nature, the transparency and open availability of energy models and data are of particular importance. Here we provide a practical how-to guide based on the collective experience of members of the Open Energy Modelling Initiative (Openmod). We discuss key steps to consider when opening code and data, including determining intellectual property ownership, choosing a licence and appropriate modelling languages, distributing code and data, and providing support and building communities. After illustrating these decisions with examples and lessons learned from the community, we conclude that even though individual researchers’ choices are important, institutional changes are still also necessary for more openness and transparency in energy research.

Poor economies not only produce less; they typically produce things that involve fewer inputs and fewer intermediate steps. Yet the supply chains of poor countries face more frequent disruptions—delivery failures, faulty parts, delays, power outages, theft, government failures—that systematically thwart the production process. To understand how these disruptions affect economic development, we model an evolving input–output network in which disruptions spread contagiously among optimizing agents. The key finding is that a poverty trap can emerge: agents adapt to frequent disruptions by producing simpler, less valuable goods, yet disruptions persist. Growing out of poverty requires that agents invest in buffers to disruptions.

Physical laws are a set of rules in the relationship between observations made by the experimenter. All these observations are made through a mechanism that links the external world to the experimenter’s awareness, a mechanism which is not under the experimenter’s control. We discuss how this mechanism can affect the physical laws as implied by the experimenter, and define fundamental physical laws as the ones which remain invariant under the change of such mechanism.

There is a strong demand for precise means for the comparison of logics in terms of expressiveness both from theoretical and from application areas. The aim of this paper is to propose a sufficiently general and reasonable formal criterion for expressiveness, so as to apply not only to model-theoretic logics, but also to Tarskian and proof-theoretic logics. For model-theoretic logics there is a standard framework of relative expressiveness, based on the capacity of characterizing structures, and a straightforward formal criterion issuing from it. The problem is that it only allows the comparison of those logics defined within the same class of models. The urge for a broader framework of expressiveness is not new. Nevertheless, the enterprise is complex and a reasonable model-theoretic formal criterion is still wanting.

In this note, we provide a conceptual explanation of a well-known polynomial identity used in algebraic number theory.

The need for modification of the Huygens-Fresnel superposition principle arises even in the description of the free fields of massive particles and, more extensively, in nonlinear field theories. A wide range of formulations and superposition schemes for secondary waves are captured by Kirchhoff’s integral theorem. We discuss various versions of this theorem as well as its connection with the superposition principle and the method of Green’s functions. A superposition scheme inherent in linear field theories, which is not based on Kirchhoff’s integral theorem but instead relies on the completeness condition, is also discussed.

The subjects mathematics and mysticism come from my main scientific interests: logic and meditation phenomena. We will discuss two types of keys for these: the personal, through inner experience, and the transpersonal, described as an objective natural process. The two types of keys exist for both subjects.

Whitehead suele ser considerado como un filósofo oscuro y extrafío por su terminología, categorías, planteamientos.. . Pero su problemática es, en el fondo, similar a la de los grandes metafísicos. El tema de la creatividad es básico en su filosofía. Creatividad es el principio último que crea e impulsa el mundo. Dios mismo es creatura de la creatividad. Pero ella no es subsistente en sí. Radica en las entidades que crea. Sólo así es concebible un mundo en proceso de autocreación. Audaz posición y difícil de conjugar metafísicamente. Trato en este trabajo de estudiarla naturaleza y función de la creatividad y de juzgar su coherencia dentro de este sistema.