I discuss the ontological assumptions and implications of General Relativity. I maintain that General Relativity is a theory about gravitational fields, not about space-time. The latter is a more basic ontological category, that emerges from physical relations among all existents. I also argue that there are no physical singularities in space-time. Singular space-time models do not belong to the ontology of the world: they are not things but concepts, i.e. defective solutions of Einstein’s field equations. I briefly discuss the actual (...) implication of the so-called singularity theorems in General Relativity and some problems related to ontological assumptions of Quantum Gravity. (shrink)
We present an axiomatization of non-relativistic Quantum Mechanics for a system with an arbitrary number of components. The interpretation of our system of axioms is realistic and objective. The EPR paradox and its relation with realism is discussed in this framework. It is shown that there is no contradiction between realism and recent experimental results.
We present a deductive theory of space-time which is realistic, objective, and relational. It is realistic because it assumes the existence of physical things endowed with concrete properties. It is objective because it can be formulated without any reference to cognoscent subjects or sensorial fields. Finally, it is relational because it assumes that space-time is not a thing but a complex of relations among things. In this way, the original program of Leibniz is consummated, in the sense that space is (...) ultimately an order of coexistents, and time is an order of succesives. In this context, we show that the metric and topological properties of Minkowskian space-time are reduced to relational properties of concrete things. We also sketch how our theory can be extended to encompass a Riemannian space-time. (shrink)
A realistic axiomatic formulation of nonrelativistic quantum mechanics for a single microsystem with spin is presented, from which the most important theorems of the theory can be deduced. In comparison with previous formulations, the formal aspect has been improved by the use of certain mathematical theories, such as the theory of equipped spaces, and group theory. The standard formalism is naturally obtained from the latter, starting from a central primitive concept: the Galilei group.
I present a formal ontological theory where the basic building blocks of the world can be either things or events. In any case, the result is a Parmenidean worldview where change is not a global property. What we understand by change manifests as asymmetries in the pattern of the world-lines that constitute 4-dimensional existents. I maintain that such a view is in accord with current scientific knowledge.
The idea of a moving present or ‘now’ seems to form part of our most basic beliefs about reality. Such a present, however, is not reflected in any of our theories of the physical world. I show in this article that presentism, the doctrine that only what is present exists, is in conflict with modern relativistic cosmology and recent advances in neurosciences. I argue for a tenseless view of time, where what we call ‘the present’ is just an emergent secondary (...) quality arising from the interaction of perceiving self-conscious individuals with their environment. I maintain that there is no flow of time, but just an ordered system of events. (shrink)
I present a discussion of some issues in the ontology of spacetime. After a characterisation of the controversies among relationists, substantivalists, eternalists, and presentists, I offer a new argument for rejecting presentism, the doctrine that only present objects exist. Then, I outline and defend a form of spacetime realism that I call event substantivalism. I propose an ontological theory for the emergence of spacetime from more basic entities. Finally, I argue that a relational theory of pre-geometric entities can give rise (...) to substantival spacetime in such a way that relationism and substantivalism are not necessarily opposed positions, but rather complementary. In an appendix I give axiomatic formulations of my ontological views. (shrink)
A supertask consists in the performance of an infinite number of actions in a finite time. I show that any attempt to carry out a supertask will produce a divergence of the curvature of spacetime, resulting in the formation of a black hole. I maintain that supertaks, contrarily to a popular view among philosophers, are physically impossible. Supertasks, literally, collapse under their own weight.
Presentism is, roughly, the metaphysical doctrine that maintains that whatever exists, exists in the present. The compatibility of presentism with the theories of special and general relativity was much debated in recent years. It has been argued that at least some versions of presentism are consistent with time-orientable models of general relativity. In this paper we confront the thesis of presentism with relativistic physics, in the strong gravitational limit where black holes are formed. We conclude that the presentist position is (...) at odds with the existence of black holes and other compact objects in the universe. A revision of the thesis is necessary, if it is intended to be consistent with the current scientific view of the universe. (shrink)
I present a discussion of some open issues in the philosophy of space-time theories. Emphasis is put on the ontological nature of space and time, the relation between determinism and predictability, the origin of irreversible processes in an expanding Universe, and the compatibility of relativity and quantum mechanics. In particular, I argue for a Parmenidean view of time and change, I make clear the difference between ontological determinism and predictability, propose that the origin of the asymmetry observed in physical processes (...) is related to the existence of cosmological horizons, and present a non-local concept of causality that can accommodate both special relativity and quantum entanglement. (shrink)
I argue for a four dimensional, non-dynamical view of space-time, where becoming is not an intrinsic property of reality. This view has many features in common with the Parmenidean conception of the universe. I discuss some recent objections to this position and I offer a comparison of the Parmenidean space-time with an interpretation of Heraclitus’ thought that presents no major antagonism.
It is a remarkable fact that all processes occurring in the observable universe are irre- versible, whereas the equations through which the fundamental laws of physics are formu- lated are invariant under time reversal. The emergence of irreversibility from the funda- mental laws has been a topic of consideration by physicists, astronomers and philosophers since Boltzmann's formulation of his famous \H" theorem. In this paper we shall discuss some aspects of this problem and its connection with the dynamics of space-time, (...) within the framework of modern cosmology. We conclude that the existence of cosmological horizons allows a coupling of the global state of the universe with the local events deter- mined through electromagnetic processes. (shrink)
I argue that there are no physical singularities in space–time. Singular space–time models do not belong to the ontology of the world, because of a simple reason: they are concepts, defective solutions of Einstein’s field equations. I discuss the actual implication of the so-called singularity theorems. In remarking the confusion and fog that emerge from the reification of singularities I hope to contribute to a better understanding of the possibilities and limits of the theory of general relativity.
We present a formal analysis of the Cosmological Argument in its two main forms: that due to Aquinas, and the revised version of the Kalam Cosmological Argument more recently advocated by William Lane Craig. We formulate these two arguments in such a way that each conclusion follows in first-order logic from the corresponding assumptions. Our analysis shows that the conclusion which follows for Aquinas is considerably weaker than what his aims demand. With formalizations that are logically valid in hand, we (...) reinterpret the natural language versions of the premises and conclusions in terms of concepts of causality consistent with (and used in) recent work in cosmology done by physicists. In brief: the Kalam argument commits the fallacy of equivocation in a way that seems beyond repair; two of the premises adopted by Aquinas seem dubious when the terms ‘cause’ and ‘causality’ are interpreted in the context of contemporary empirical science. Thus, while there are no problems with whether the conclusions follow logically from their assumptions, the Kalam argument is not viable, and the Aquinas argument does not imply a caused origination of the universe. The assumptions of the latter are at best less than obvious relative to recent work in the sciences. We conclude with mention of a new argument that makes some positive modifications to an alternative variation on Aquinas by Le Poidevin, which nonetheless seems rather weak. (shrink)
I offer a formal ontological theory where the basic building blocks of the world are timeless events. The composition of events results in processes. Spacetime emerges as the system of all events. Things are construed as bundles of processes. I maintain that such a view is in accord with General Relativity and offers interesting prospects for the foundations of classical and quantum gravity.
I offer an analysis of the Principle of Sufficient Reason and its relevancy for the scientific endeavour. I submit that the world is not, and cannot be, rational—only some brained beings are. The Principle of Sufficient Reason is not a necessary truth nor a physical law. It is just a guiding metanomological hypothesis justified a posteriori by its success in helping us to unveil the mechanisms that operate in Nature.
Desde la llegada al poder de Hugo Chávez, en las elecciones de 1998, comenzó la configuración de unas nuevas relaciones de poder en el sistema político venezolano (SPV). Estas relaciones estaban determinadas por la naturaleza de los actores políticos que accedieron al poder, el funcionamiento ..
Este artigo aborda o combate que empreendeu Gustavo Corção à juventude católica brasileira nas páginas do Diário de Notícias e d’ O Globo entre as décadas de 1950 e de 1960. No caso em tela, interessa-nos entender as reações de Gustavo Corção às mudanças na sociedade e na Igreja Católica entre 1957 e 1964. A hipótese é que as críticas de Corção explicitam o conflito entre duas gerações de católicos: uma conservadora; a dele; e outra progressista, a das (...) organizações de jovens católicos, mais especificamente, a da Juventude Universitária Católica (JUC). Apresentaremos a disputa a partir do exame da seguinte questão: o papel que a juventude brasileira deveria desempenhar naqueles anos. O objetivo é mostrar que suas críticas à opção de ação temporal assumida pelas organizações de juventude católica devem ser lidas pela chave do conflito geracional que marcou o campo católico brasileiro. Palavras-chave : Catolicismo. Gerações. Gustavo Corção. Juventude católica.: This paper discusses the fight of Brazilian Catholic Youth Gustavo Corção in the newspapers Diário de Notícias and O Globo in the 1950s and 1960s. In case we are interested in understanding the reactions of Gustavo Corção to changes in society and the Catholic Church between 1957 and 1964. The hypothesis is that the criticism of Corção explains the conflict between two generations of Catholics: a conservative and other progressive, represented by the Catholic youth organizations, more specifically, the Youth Catholic University. We are going to examine the question: the role that Brazilian youth should play in those years. Therefore, the aim is to show that his criticism of the political action undertaken by the young catholic organizations should be read by the key of generation conflict which has marked the Brazilian Catholic field. Key words: Catholicism. Generations. Gustavo Corção. Catholic youth organizations. (shrink)
I discuss the recent claims made by Mario Bunge on the philosophical implications of the discovery of gravitational waves. I think that Bunge is right when he points out that the detection implies the materiality of spacetime, but I reject his identification of spacetime with the gravitational field. I show that Bunge’s analysis of the spacetime inside a hollow sphere is defective, but this in no way affects his main claim.
I offer a theory of art that is based on science. I maintain that, as any other human activity, art can be studied with the tools of science. This does not mean that art is scientific, but aesthetics, the theory of art, can be formulated in accord with our scientific knowledge. I present elucidations of the concepts of aesthetic experience, art, work of art, artistic movement, and I discuss the ontological status of artworks from the point of view of scientific (...) philosophy. (shrink)
Macroscopic irreversible processes emerge from fundamental physical laws of reversible character. The source of the local irreversibility seems to be not in the laws themselves but in the initial and boundary conditions of the equations that represent the laws. In this work we propose that the screening of currents by black hole event horizons determines, locally, a preferred direction for the flux of electromagnetic energy. We study the growth of black hole event horizons due to the cosmological expansion and accretion (...) of cosmic microwave background radiation, for different cosmological models. We propose generalized McVittie co-moving metrics and integrate the rate of accretion of cosmic microwave background radiation onto a supermassive black hole over cosmic time. We find that for flat, open, and closed Friedmann cosmological models, the ratio of the total area of the black hole event horizons with respect to the area of a radial co-moving space-like hypersurface always increases. Since accretion of cosmic radiation sets an absolute lower limit to the total matter accreted by black holes, this implies that the causal past and future are not mirror symmetric for any spacetime event. The asymmetry causes a net Poynting flux in the global future direction; the latter is in turn related to the ever increasing thermodynamic entropy. Thus, we expose a connection between four different “time arrows”: cosmological, electromagnetic, gravitational, and thermodynamic. (shrink)
No livro “As vozes da igualdade” (“Las voces de la igualdad. Bases para una teoría crítica de la justicia”. Ed. Proteus, 2010. 288 páginas – Ainda sem tradução para o português), o Prof. Dr. Gustavo Pereira, da Universidad de la Republica, Uruguai, procura analisar estas questões investigando as principais teorias de justiça contemporâneas que pretendem respondê-las e apresenta sua proposta de um caminho para a fundamentação de uma teoria crítica de justiça renovada, mais abrangente, que ofereça meios mais adequados (...) e eficazes para promover a justiça social e desenvolver as capacidades humanas necessárias para a construção de uma “eticidade democrática”. (shrink)
O artigo se confronta com a problemática da relação entre teologia e ciências sociais. Sua pretensão é formular adequadamente os termos dessa relação, explicitando a importância, a função e o lugar das ciências sociais na elaboração do discurso teológico e no produto teológico. Começa apresentando o debate sobre a relação entre teologia e ciências sociais na América Latina nas últimas décadas através de seus principais interlocutores: Gustavo Gutiérrez e Clodovis Boff; Juan Luis Segundo e Ignácio Ellacuría. E conclui, esboçando, (...) de modo sistemático, ainda que em forma de tese, a estrutura teórica fundamental dessa relação. Ela tem a ver com o conhecimento da realidade na qual se vive a fé e que deve ser pensada teologicamente; com a dimensão social do reinado de Deus, assunto da teologia cristã; com o caráter social da teologia, enquanto teoria; e com a suspeita ideológica e o processe de des-ideologização e libertação da teologia. Palavras-chave: Social. Teologia. Ciências sociais. Mediação.This article presents the issue of the relationship between theology and the social sciences. For this purpose, the author seeks to formulate the terms of the relationship of these two areas of Knowledge, highlighting the importance, the role and the place of the social sciences in the development of the theological discourse and of the theological product. At the beginning of the text the author presents a discussion on the relationship between theology and the social sciences in Latin America in recent decades through its main representatives: Gustavo Gutierrez and Clodovis Boff, Juan Luis Segundo and Ignacio Ellacuria. The paper also presents a systematic outline of the fundamental theoretical framework of the relationship between theology and the social sciences, showing that this relationship binds to the knowledge of the reality in which faith is placed. In conclusion, the texts highlights that faith must be considered theologically on three levels: with the social dimension of the Kingdom of God, which is an issue of Christian Theology; with the social character of theology as a theory; with the ideological suspicion and with the process of liberation of theology. Key-words : Social. Theology. Social Sciences. Mediation. (shrink)
A luta pela justiça e libertação encontra-se no centro dos movimentos e das reflexões teológicas latino-americanas há décadas. De que modo os movimentos sociais, os líderes políticos, os teólogos e os cristãos tratam atualmente os desafios da mudança climática? Como eles os relacionam no contexto global? O presente artigo, baseado numa apresentação feita pelo autor para uma audiência nórdica européia apresenta a gênesis e a matriz das teologias latino-americanas e alguns de seus principais expoentes como Leonardo Boff, Juan Luis Segundo, (...)Gustavo Gutierrez. Destaca também os novos empreendimentos que permitem uma abordagem dos assuntos relacionados às mudanças clímaticas, nomeados de teologias indígenas, eco-teologias, teologia e economia e teologia eco-feminista, construídos a partir das publicações de teólogos como Boff e Ivone Gebara. Em seguida, o autor destaca algumas das principais componentes desta relação, enfocando o imperativo ético de justiça climática, a renovada teologia da criação e da dimensão espiritual da abordagem. Palavras-chave : Teologia latino-americana, ecologia, alterações climáticas, ética, justiçaThe struggle for justice and liberation has been at the core of mouvements and theological reflection in Latin America for decades. How do social mouvements, political leaders, theologians and Christians address nowadays the challenges of climate change? What ethical and spiritual avenues are proposed? How to relate them to the global context? The present article, based on a presentation made by the author to a Nordic European audience, presents the genesis and matrix of Latin American theologies, some of their key authors like Leonardo Boff, Juan Luis Segundo, Gustavo Gutierrez and highlights new developments that have allowed an approach to climate change issues, namely, indigenous theology, eco-theology, theology and economy and eco-feminist theology, building on work done by theologians like Boff and Ivone Gebara. Then the author stresses some of the core components of this relation, focusing on the ethical imperative of climate justice, the renewed theology of creation and the spiritual dimension of the approach. Key words : Latin American theology, ecology, climate change, ethics, justice. (shrink)
Partiendo del presupuesto que el lenguaje humano es forma y/o lugar de acción e interacción con el mundo y los otros, entendemos los procesos de lectura,interpretación y escritura como acciones cognitivo-sociales formadoras del sujeto del conocimiento. De ese modo, nos gustaría reflejar sobre los modos de leer y los modos de escribir practicados y enseñados durante la vida académica. Basados en nuestra experiencia docente, en un corpus de pesquisa en marcha en la UESB-Jequié, y en los enfoques teóricos adoptadas (Ingedore (...) Koch, Gustavo Bernardo, Mary Kato) este trabajo busca indagar la docentes y discentes cuáles los principales beneficios que la lectura y la producción de texto pueden proporcionar. (shrink)
Gustavo Machado, pertenece a la generación de intelectuales que se nutrió fundamentalmente de la doctrina marxista e hizo de ella la herramienta para desarrollar la interpretación de nuestra realidad. Este estudio recoge referencias sobre su vida, analiza su postura antiimperialista y la defensa que hace de la democracia participativa. Además desarrolla su postura ante la educación, la iglesia y su concepción de la historia.