Investigating transition state resonances in the time domain by means of Bohmian mechanics: The F+HD reaction

In this work, we investigate the existence of transition state resonances on atom-diatom reactive collisions from a time-dependent perspective, stressing the role of quantum trajectories as a tool to analyze this phenomenon. As it is shown, when one focusses on the quantum probability current density, new dynamical information about the reactive process can be extracted. In order to detect the effects of the different rotational populations and their dynamics/coherences, we have considered a reduced two-dimensional dynamics obtained from the evolution of a full three-dimensional quantum time-dependent wave packet associated with a particular angle. This reduction procedure provides us with information about the entanglement between the radial degrees of freedom (r,R) and the angular one (\gamma), which can be considered as describing an environment. The combined approach here proposed has been applied to study the F+HD reaction, for which the FH+D product channel exhibits a resonance-mediated dynamics.Comment: 12 pages, 9 figure

Signatures of Non-Standard Electroweak Symmetry Breaking

This is the write-up of a talk given at the EW session in Moriond (March 2012). I summarize some non-standard electroweak scenarios, and how they predict the existence of new spin-two resonances. Spin-two resonances, whether coming from the compactification of extra-dimensions or from a new sector of strong interactions, exhibit the same interactions with the Standard Model. This is a consequence of Lorentz and CP invariance, which we assume would be preserved by the new strong sector. Although this would seem to support the holographic duality between strongly interacting theories in four-dimensions and extra-dimensional theories, I show that there is a way to distinguish between the two sides of the "duality", which constitutes an explicit example of its breakdown

How far can a pragmatist go into quantum theory? - A critical view of our current understanding of quantum phenomena

To date, quantum mechanics has proven to be our most successful theoretical model. However, it is still surrounded by a "mysterious halo" that can be summarized in a simple but challenging question: Why quantum phenomena are not understood under the same logic as classical ones? Although this is an open question (probably without an answer), from a pragmatist's point of view there is still room enough to further explore the quantum world, marveling ourselves with new physical insights. We just need to look back in the historical evolution of the quantum theory and thoroughly reconsider three key issues: (1) how this has developed since its early stages at a conceptual level, (2) what kind of experiments can be performed at present in a laboratory, and (3) what nonstandard conceptual models are available to extract some extra information. This contribution is aimed at providing some answers (and, perhaps, also raising some issues) to these questions through one of such models, namely Bohmian mechanics, a hydrodynamic formulation of the quantum theory, which is currently trying to open new pathways of understanding. Specifically, the Chapter constitutes a brief and personal overview on the historic and contextual evolution of this quantum formulation, its physical meaning and interest (leaving aside metaphysical issues), and how it may help to overcome some preconceived paradoxical aspects of the quantum theory.Comment: 11 pages, 2 figures; contribution to "Particle and Astroparticle Physics, Gravitation and Cosmology: Predictions, Observations and New Projects" (Proceedings of the XXXth International Workshop on High Energy Physics), eds. V. Petrov and R. Ryutin (World Scientific, Singapore, 2015), pp. 161-17

Modelling Personal Income Taxation in Spain:Revenue Elasticities and Regional Comparisons

This paper derives analytical expressions for the revenue elasticity of the Spanish personal income tax system, as applied to tax units and in aggregate. This is complicated by the schedular nature of the system, and the role of central and regional governments, along with the existence of a range of tax credits and eligible expenditures and deductions. Empirical estimates are obtained using a cros -sectional dataset which enables a number of important ancillary elasticities (relating to allowances and tax credits, and different income sources) to be estimated. It was found that there is considerable variation among tax units in the revenue elasticity, with highly (positively) skewed distributions. The nature of the distributions varies among regions of Spain, and the aggregate elasticities for each region were found to display some variation associated with income distribution differences. The national aggregate is found to be around 1.3. The paper also derives aggregate tax revenue as a function of characteristics of the distribution of taxable income in each region. This allows the sources of revenue differences among regions to be identified.

Regularity of radial stable solutions to semilinear elliptic equations for the fractional Laplacian

We study the regularity of stable solutions to the problem $$\left\{ \begin{array}{rcll} (-\Delta)^s u &=& f(u) & \text{in} \quad B_1\,, u &\equiv&0 & \text{in} \quad \mathbb R^n\setminus B_1\,, \end{array} \right.$$ where $s\in(0,1)$. Our main result establishes an $L^\infty$ bound for stable and radially decreasing $H^s$ solutions to this problem in dimensions $2 \leq n < 2(s+2+\sqrt{2(s+1)})$. In particular, this estimate holds for all $s\in(0,1)$ in dimensions $2 \leq n\leq 6$. It applies to all nonlinearities $f\in C^2$. For such parameters $s$ and $n$, our result leads to the regularity of the extremal solution when $f$ is replaced by $\lambda f$ with $\lambda > 0$. This is a widely studied question for $s=1$, which is still largely open in the nonradial case both for $s=1$ and $s<1$

Democracy and technological politic in the risk society

New technologies generate risks, for the evaluation of which various mechanisms have been developed; the most frequent of these mechanisms consists of advice from committees of experts to the bodies whose role is to decide whether a new technology should be implemented or not. Such committees try to measure the magnitude of the threats that accompany the introduction of a new technology in order that the policy-makers may take their decisions in the light of the reports of the experts. The legitimacy of such reports is not only found in the technical capacity of its authors, but also in the impartiality of their recommendations. On numerous occasions, nevertheless, the effective presence of this evaluation finds itself today under suspicion. There are various methods that can be employed to try to resolve this problem. Firstly by reinforcing the mechanisms on which the technocratic evaluation of the risk are based; for example, through transparency in the selection of the experts. Secondly, by means of the incorporation of democratic mechanisms in the scientific-technological policy. The exposure of the internal conditions to the dynamics of the technological change that make possible the institutionalised involvement of society in the control of risk, as well as of the mechanisms to realise it are the principal subjects of this work