A Non-Reductionist Solution to the Problem of Social Causation

The thesis of the causal closure of the physical world renders mental and social causation philosophically problematic. In The Construction of Social Reality, John Searle offers a partial solution to the problem of the causal efficacy of social and institutional facts by an appeal to the notion of the Background, or, as I will argue, by an appeal to its physical components. Since Searle's solution refers to physical facts in order to explain social causation, it does not seem to differ from the solution offered by reductive physicalists to the problem of mental causation. In this paper, I will discuss both responses to these two problems of higher-order causation. As a result of this investigation, the paper offers an account of how and to what extent does Searle's solution solve the problem of the causal efficacy of social facts, without implying their reducibility to physical facts

Spinwave damping in the two-dimensional ferromagnetic XY model

The effect of damping of spinwaves in a two-dimensional classical ferromagnetic XY model is considered. The damping rate $\Gamma_{q}$ is calculated using the leading diagrams due to the quartic-order deviations from the harmonic spin Hamiltonian. The resulting four-dimensional integrals are evaluated by extending the techniques developed by Gilat and others for spectral density types of integrals. $\Gamma_{q}$ is included into the memory function formalism due to Reiter and Solander, and Menezes, to determine the dynamic structure function $S(q,\omega)$. For the infinite sized system, the memory function approach is found to give non-divergent spinwave peaks, and a smooth nonzero background intensity (``plateau'' or distributed intensity) for the whole range of frequencies below the spinwave peak. The background amplitude relative to the spinwave peak rises with temperature, and eventually becomes higher than the spinwave peak, where it appears as a central peak. For finite-sized systems, there are multiple sequences of weak peaks on both sides of the spinwave peaks whose number and positions depend on the system size and wavevector in integer units of $2\pi/L$. These dynamical finite size effects are explained in the memory function analysis as due to either spinwave difference processes below the spinwave peak or sum processes above the spinwave peak. These features are also found in classical Monte Carlo -- Spin-Dynamics simulations.Comment: 20 two-column page

Sobre a atribuição coletiva de características a artefatos

The common notion of artifacts characterizes them as the products of successful activities of their makers, guided by intentions that such objects would instantiate certain features, such as their specific functions. Many counterexamples, however, reveal the unsuitability of the common notion. In the face of this acknowledgment, the paper explores the possibility that features of artifacts, and more specifically, the possession of their functions, may arise, at least partially, from collective assignments. In order to achieve the mentioned goal, the paper critically examines some notions and theses put forward by John Searle (1996; 2010) and others. Its main result, however, consists in offering and elucidating an original thesis, namely, that the functions of many artifacts would be maintained, partially, by forms of continuous collective intentionality, which can involve conscious or unconscious, active or inactive collective intentional states. Keywords: Artifacts, assignment of function, collective intentionality, maintenance of function.A noção comum de artefatos os caracteriza como produtos de atividades bem-sucedidas de seus fabricantes, orientadas por intenções de que tais objetos instanciassem determinadas características, tais como suas funções específicas. Diversos contraexemplos, no entanto, revelam a inadequação da noção comum. Diante dessa constatação, o artigo explora a possibilidade de que características de artefatos, e mais especificamente, a posse de suas funções, possam decorrer, ao menos em parte, de atribuições coletivas. Para atingir o referido objetivo, o artigo examina de forma crítica algumas noções e teses propostas por John Searle (1996; 2010) e outros. Seu principal resultado, no entanto, consiste em oferecer e elucidar uma tese original, a saber, que as funções de muitos artefatos seriam mantidas, parcialmente, por formas de intencionalidade coletiva contínua, que podem conter estados intencionais coletivos conscientes ou inconsciente, ativos ou inativos. Palavras-chave: Artefatos, atribuição de função, intencionalidade coletiva, manutenção de função.A noção comum de artefatos os caracteriza como produtos de atividades bem-sucedidas de seus fabricantes, orientadas por intenções de que tais objetos instanciassem determinadas características, tais como suas funções específicas. Diversos contraexemplos, no entanto, revelam a inadequação da noção comum. Diante dessa constatação, o artigo explora a possibilidade de que características de artefatos, e mais especificamente, a posse de suas funções, possam decorrer, ao menos em parte, de atribuições coletivas. Para atingir o referido objetivo, o artigo examina de forma crítica algumas noções e teses propostas por John Searle (1996; 2010) e outros. Seu principal resultado, no entanto, consiste em oferecer e elucidar uma tese original, a saber, que as funções de muitos artefatos seriam mantidas, parcialmente, por formas de intencionalidade coletiva contínua, que podem conter estados intencionais coletivos conscientes ou inconsciente, ativos ou inativos. Palavras-chave: Artefatos, atribuição de função, intencionalidade coletiva, manutenção de função

Bi-large neutrino mixing and the Cabibbo angle

Recent measurements of the neutrino mixing angles cast doubt on the validity of the so-far popular tri-bimaximal mixing ansatz. We propose a parametrization for the neutrino mixing matrix where the reactor angle seeds the large solar and atmospheric mixing angles, equal to each other in first approximation. We suggest such bi-large mixing pattern as a model building standard, realized when the leading order value of the reactor angle equals the Cabibbo angle.Comment: 4 pages, 2 figs. v2: matches version appearing in Phys.Rev.D, rapid communication

Phenomenological implications of neutrinos in extra dimensions

Standard Model singlet neutrinos propagating in extra dimensions induce small Dirac neutrino masses. While it seems rather unlikely that their Kaluza-Klein excitations directly participate in the observed neutrino oscillations, their virtual exchange may lead to detectable signatures in future neutrino experiments and in rare charged lepton processes. We show how these effects can be described by specific dimension-six effective operators and discuss their experimental signals

Levantamento de reconhecimento de média intensidade dos solos da Gleba Machadinho, RO.

O trabalho divulga o resultado da identificação e o levantamento de reconhecimento de média intensidade dos solos do Projeto de Assentamento Gleba Machadinho, nos municípios de Machadinho d`Oeste e Anari, R0