Hemeroteca de la sección ‘Ambiente’

Fundamental Materials Research and the Course of Human Civilization

Por • 12 ago, 2017 • Category: Ambiente

Unless we change direction, we are likely to wind up where we are headed. (Ancient Chinese proverb)

The Limits to Machine Consciousness

Por • 30 jul, 2017 • Category: Ambiente

It is generally accepted that machines can replicate cognitive tasks performed by conscious agents as long as they are not based on the capacity of awareness. We consider several views on the nature of subjective awareness, which is fundamental for self-reflection and review, and present reasons why this property is not computable. We argue that consciousness is more than an epiphenomenon and assuming it to be a separate category is consistent with both quantum mechanics and cognitive science. We speak of two kinds of consciousness, little-C and big-C, and discuss the significance of this classification in analyzing the current academic debates in the field. The interaction between the system and the measuring apparatus of the experimenter is examined both from the perspectives of decoherence and the quantum Zeno effect. These ideas are used as context to address the question of limits to machine consciousness.

Pitman sampling formula and an empirical study of choice behavior

Por • 26 jul, 2017 • Category: Ambiente

This study discusses choice behavior using a voting model in which voters can obtain information from a finite number r of previous voters. Voters vote for a candidate with a probability proportional to the previous vote ratio, which is visible to the voters. We obtain Pitman sampling formula as the equilibrium distribution of r votes. We present the model as a process of making posts on a bulletin board system, 2ch.net, where users can choose one of many threads to create a post. We explore how this choice depends on the last r posts and the distribution of r posts across threads. We conclude that the posting process is described by our voting model for a small r , which might correspond to the time horizon of users’ response.

Intuitionistic modal logic based on neighborhood semantics without superset axiom

Por • 20 jul, 2017 • Category: Ambiente

In this paper we investigate certain systems of propositional logic defned semantically in terms of neighborhood structures. These systems have both intuitionistic and modal aspects. We discuss various restrictions imposed on our models (i.e. on the defnition of neighborhood function) but our constant approach is to discard superset axiom. Such modifcation allows us to think about specifc modalities Δ and new functor ⇝ depending on the notion of maximal neighborhood. We show how it is possible to treat maximal neighborhoods like topological spaces. Also, we describe properties of bounded morphism, bisimulation and n-bisimulation in our semantics. Finally, we analyze the concept of canonical models.

Bohm’s approach to quantum mechanics: Alternative theory or practical picture?

Por • 16 jul, 2017 • Category: Ambiente

Since its inception Bohmian mechanics has been generally regarded as a hidden-variable theory aimed at providing an objective description of quantum phenomena. To date, this rather narrow conception of Bohm’s proposal has caused it more rejection than acceptance. Now, after 65 years of Bohmian mechanics, should still be such an interpretational aspect the prevailing appraisal? Why not favoring a more pragmatic view, as a legitimate picture of quantum mechanics, on equal footing in all respects with any other more conventional quantum picture? These questions are used here to introduce a pedagogical discussion at an elementary level, suitable for undergraduate students, on how to deal with Bohmian mechanics at present, enhancing its aspect as an efficient and useful picture or formulation to tackle, explore, describe and explain quantum phenomena where phase and correlation (entanglement) are key elements. This discussion is presented through two building blocks.

Challenges to Keeping the Computer Industry Centered in the US

Por • 10 jul, 2017 • Category: Ambiente

It is undeniable that the worldwide computer industry’s center is the US, specifically in Silicon Valley. Much of the reason for the success of Silicon Valley had to do with Moore’s Law: the observation by Intel co-founder Gordon Moore that the number of transistors on a microchip doubled at a rate of approximately every two years. According to the International Technology Roadmap for Semiconductors, Moore’s Law will end in 2021. How can we rethink computing technology to restart the historic explosive performance growth? Since 2012, the IEEE Rebooting Computing Initiative (IEEE RCI) has been working with industry and the US government to find new computing approaches to answer this question. In parallel, the CCC has held a number of workshops addressing similar questions. This whitepaper summarizes some of the IEEE RCI and CCC findings.

Lecciones del rentismo: lo que Venezuela no debe olvidar

Por • 24 jun, 2017 • Category: Ambiente

En la IV República un alto porcentaje del ingreso petrolero se destinó a financiar el capitalismo rentístico con préstamos a bajas tasas de interés y largos plazos; la asignación de petrodólares baratos para importar maquinarías, insumos y tecnología; así como compras gubernamentales en condiciones muy favorables para la producción nacional. En la V República el mayor porcentaje de los ingresos petroleros se utilizó para financiar el neo-rentismo socialista como un modelo de dominación sustentado en el uso del ingreso petrolero para financiar la inversión social y crear una red clientelar que le sirve de apoyo político. El capitalismo rentístico y el neo-rentismo socialista son expresiones distintas del mismo modelo de acumulación extractivista. Los actores económicos, políticos y sociales se acostumbran a obtener ganancias e ingresos que no son fruto de su propia inversión ni de su trabajo productivo.

La formalisation de la dialectique de Hegel. Bilan de quelques tentatives

Por • 7 jun, 2017 • Category: Ambiente

La dialectique hégélienne et marxiste a fait l’objet des années 50 aux années 70 de diverses tentatives de transpositions1 dans le langage de la logique formelle. Diverses raisons ont contribué à une telle entreprise. Tout d’abord il s’agissait de concilier deux secteurs de la logique qui avaient à l’époque le vent en poupe. Le formalisme logique s’était développé de façon fulgurante depuis le XIXe siècle et avait été identifié au langage même de la science, tandis que le marxisme jouissait dans l’après-guerre d’un prestige considérable, lui assurant les faveurs d’un grand nombre d’intellectuels. N’était-il pas tentant d’essayer de réconcilier les deux en passant outre aux réticences clairement exprimées dès leurs époques respectives par Hegel et Marx? D’autre part, un recours à la formalisation de la dialectique, s’il réussissait, aurait permis de savoir exactement en quoi consistait effectivement la logique hégélienne, mettant un coup d’arrêt définitif aux spéculations oiseuses fondées sur une définition trop floue de sa nature.

Brouwer and Euclid

Por • 26 may, 2017 • Category: Ambiente

We explore the relationship between Brouwer’s intuitionistic mathematics and Euclidean geometry. Brouwer wrote a paper in 1949 called “The contradictority of elementary geometry”. In that paper, he showed that a certain classical consequence of the parallel postulate implies Markov’s principle, which he found intuitionistically unacceptable. But Euclid’s geometry, having served as a beacon of clear and correct reasoning for two millenia, is not so easily discarded. Brouwer started from a “theorem” that is not in Euclid, and requires Markov’s principle for its proof. That means that Brouwer’s paper did not address the question whether Euclid’s “Elements” really requires Markov’s principle. In this paper we show that there is a coherent theory of “non-Markovian Euclidean geometry.”

Process Ontology from Whitehead to Quantum Physics

Por • 16 may, 2017 • Category: Ambiente

Abstract Although Alfred North Whitehead probably did not know of the new quantum theory of Heisenberg, Schr¨odinger and Dirac, there seem to be deep similarities between his idea of the process and the ideas of quantum theory. Both Whitehead’s metaphysics and quantum theory are theories of observations: The realities which quantum theory deals with are certain observations by scientists who use the theory. Finally, Whitehead’s speculative cosmology is an expansion and generalization of the British empiricists’ theory of perception. By characterizing the basic ideas of scientific development and their consequences for philosophy, Whitehead wants to unify different views of the nature of things and to overcome the dualistic tradition of Cartesianism in modernity. Four leading ideas have determined the theoretical sciences in the 19th century: Atomicity, continuity, energy preservation and evolution. According to Whitehead, the challenge to science was not to introduce these concepts but to fuse them together and expand their application. Therefore, the cell theory and Pasteur’s work were more revolutionary for him than the achievement of Dalton’s nuclear theory, “for they introduced the notion of organism into the world of minute beings. […] The doctrine of evolution has to do with the emergence of novel organisms as the outcome of chance.” [34, p. 95]