Search results for "Formalism"
showing 10 items of 357 documents
El formalismo interpretativo y el iusnaturalismo actual: la posición de John Finnis | The Interpretive Formalism and the Current Iusnaturalism: The P…
2014
Resumen: Hoy podemos ver un resurgimiento de las tendencias formalistas en la interpretación de reglas jurídicas. Este resurgimiento aparece en los campos tanto del Positivismo jurídico como del Iusnaturalismo. La finalidad de estos movimientos es ética y política: la defensa del imperio de la ley. Un ejemplo de esta actitud formalista es la teoría de John Finnis. Pero el formalismo no resuelve todos los problemas. Incluso desde el punto de vista de una teoría de la decisión judicial no decisionista, la interpretación jurídica necesita la ayuda de herramientas hermenéuticas no formales para completar su función. Abstract: Today, we can see a revival of formalist tendencies in the interpre…
Philosophy of Mathematics and Ontological Commitment
2000
This paper concerns Quine's classification of philosophies of mathematics as sketched in "On what there is" and offers a new reading of Quine's view. In his famous paper Quine defines three positions: Realism, Conceptualism, and Nominalism. Each of them, he says, has its modern expression, respectively, in Logicism, Intuitionism, and Formalism. According to Quine these foundational positions can be accepted or rejected on a clear and objective basis, according to their distinctive ontological commitments. Consistent with his own criterion for ontological commitment (buttressed by his view on impredicative definitions), Quine adopts the Realist (or the Platonist) position in mathematics. Lat…
Density functional calculation of stopping power of an electron gas for slow ions
1981
Abstract We describe the first calculation of the stopping power of an electron gas for slow ions using the density-functional formalism. We evaluate the nonlinear self-consistent potential around the ion and from scattering theory determine the energy loss directly. Comparison with the results of linear theory is made.
Shell-Model Effective Operators for Muon Capture in ^{20}Ne
1999
It has been proposed that the discrepancy between the partially-conserved axial-current prediction and the nuclear shell-model calculations of the ratio $C_P/C_A$ in the muon-capture reactions can be solved in the case of ^{28}Si by introducing effective transition operators. Recently there has been experimental interest in measuring the needed angular correlations also in ^{20}Ne. Inspired by this, we have performed a shell-model analysis employing effective transition operators in the shell-model formalism for the transition $^{20}Ne(0^+_{g.s.})+\mu^- \to ^{20}F(1^+; 1.057 MeV) + \nu_\mu$. Comparison of the calculated capture rates with existing data supports the use of effective transiti…
Neutron-proton pairing correlations in a single l-shell model
2017
The long standing problem of neutron-proton pairing correlations is revisited by employing the Hartree-Fock-Bogoliubov formalism with neutron-proton mixing in both the particle-hole and particle-hole channels. We compare numerical calculations performed within this method with an exact pairing model based on the $SO(8)$ algebra. The neutron-proton mixing is included in our calculations by performing rotations in the isospin space using the isocranking technique.
Generalization of the model-independent Laurent–Pietarinen single-channel pole-extraction formalism to multiple channels
2016
A method to extract resonance pole information from single-channel partial-wave amplitudes based on a Laurent (Mittag-Leffler) expansion and conformal mapping techniques has recently been developed. This method has been applied to a number of reactions and provides a model-independent extraction procedure which is particularly useful in cases where a set of amplitudes is available only at discrete energies. This method has been generalized and applied to the case of a multi-channel fit, where several sets of amplitudes are analyzed simultaneously. The importance of unitarity constraints is discussed. The final result provides a powerful, model-independent tool for analyzing partial-wave amp…
Dynamically generated resonances
2009
In this talk I report on recent work related to the dynamical generation of baryonic resonances, some made up from pseudoscalar meson-baryon, others from vector meson-baryon and a third type from two meson-one baryon systems. We can establish a correspondence with known baryonic resonances, reinforcing conclusions previously drawn and bringing new light on the nature of some baryonic resonances of higher mass.
Baryon Resonances
2010
10th International Conference on Hypernuclear and Strange Particle Physics. Tokai, JAPAN, SEP 14-18, 2009
Interaction of vector mesons with baryons and nuclei
2012
After some short introductory remarks on particular issues on the vector mesons in nuclei, in this paper we present a short review of recent developments concerning the interaction of vector mesons with baryons and with nuclei from a modern perspective using the local hidden gauge formalism for the interaction of vector mesons. We present results for the vector baryon interaction and in particular for the resonances which appear as composite states, dynamically generated from the interaction of vector mesons with baryons, taking also the mixing of these states with pseudoscalars and baryons into account. We then venture into the charm sector, reporting on hidden charm baryon states around 4…
Dynamically generated resonances from the vector octet-baryon octet interaction
2010
We study the interaction of vector mesons with the octet of stable baryons in the framework of the local hidden gauge formalism using a coupled-channels unitary approach. We examine the scattering amplitudes and their poles, which can be associated to known J(P) = 1/2(-), 3/2(-) baryon resonances, in some cases, or give predictions in other ones. The formalism employed produces doublets of degenerate J(P) = 1/2(-), 3/2(-) states, a pattern which is observed experimentally in several cases. The findings of this work should also be useful to guide present experimental programs searching for new resonances, in particular in the strange sector where the current information is very poor.