Quantum correlations in continuos-time quantum walks of two indistinguishable particles

We evaluate the degree of quantum correlation between two fermions (bosons) subject to continuous time quantum walks in a one-dimensional ring lattice with periodic boundary conditions. In our approach, no particle-particle interaction is considered. We show that the interference effects due to exchange symmetry can result into the appearance of non-classical correlations. The role played onto the appearance of quantum correlations by the quantum statistics of the particles, the boundary conditions, and the partition of the system is widely investigated. Quantum correlations also been investigated in a model mimicking the ballistic evolution of two indistinguishable particles in a 1D continuous space structure. Our results are consistent with recent quantum optics and electron quantum optics experiments where the showing up of two-particle non-classical correlations has been observed even in the absence of mutual interaction between the particles.Comment: 12 pages, 5 figure

Placebo-Induced Improvements: How Therapeutic Rituals Affect the Patient's Brain

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Factores auto-percibidos de eficiencia grupal en una comunidad lúdica on-line

Setenes Jornades de Foment de la Investigació de la FCHS (Any 2001-2002

Efectos de tempo y modo sobre el contenido emocional de la música

Novenes Jornades de Foment de la Investigació de la FCHS (Any 2003-2004)La relación entre música y emociones es evidente (Juslin & Sloboda, 2001), pero el acercamiento efectuado por la psicología se ha centrado casi siempre en “gestalt” musicales antes que en los parámetros de la música misma hasta fechas muy recientes. En el marco de esta indagación psicológica de la influencia de los parámetros musicales sobre las emociones humanas, se propone una primera exploración con cuatro condiciones experimentales, fruto de la modificación de una melodía neutra en dos factores – tempo y modo, cada uno dividido en dos niveles. Se recogieron los juicios sobre el contenido emocional de cada una de las cuatro melodías mediante una página web programada a propósito, teniendo que puntuar cada melodía en cuatro emociones básicas mediante una escala tipo Likert de cinco puntos. Los resultados parecen apoyar una teoría paramétrica de la influencia de la música sobre las emociones

Non-Markovian continuous-time quantum walks on lattices with dynamical noise

We address the dynamics of continuous-time quantum walks on one-dimensional disordered lattices inducing dynamical noise in the system. Noise is described as time-dependent fluctuations of the tunneling amplitudes between adjacent sites, and attention is focused on non-Gaussian telegraph noise, going beyond the usual assumption of fast Gaussian noise. We observe the emergence of two different dynamical behaviors for the walker, corresponding to two opposite noise regimes: slow noise (i.e. strong coupling with the environment) confines the walker into few lattice nodes, while fast noise (weak coupling) induces a transition between quantum and classical diffusion over the lattice. A phase transition between the two dynamical regimes may be observed by tuning the ratio between the autocorrelation time of the noise and the coupling between the walker and the external environment generating the noise. We also address the non-Markovianity of the quantum map by assessing its memory effects, as well as evaluating the information backflow to the system. Our results suggest that the non-Markovian character of the evolution is linked to the dynamical behavior in the slow noise regime, and that fast noise induces a Markovian dynamics for the walker.Comment: 10 pages, 8 figure

Response to: 'Correspondence on 'Long-term efficacy and safety of canakinumab in patients with colchicine-resistant familial Mediterranean fever: results from the randomised phase III CLUSTER trial'' by Satis<i>et al</i>

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What is the relative contribution of biological and psychosocial factors to the generation of hypoxia headache?

ABSTRACTBackground: The biopsychosocial model claims that illness is generated by both biological and psychosocial factors. Accordingly, several studies have shown that both factors contribute to the generation of pain.Aims: The aim of the present study is to manipulate biological, psychological, and social factors in hypobaric hypoxia headache in order to understand their relative contribution to the generation of headache pain.Methods: Healthy subjects were subdivided into three groups and brought to our high-altitude labs for the assessment of hypoxia-induced headache, blood oxygen saturation (SO2), prostaglandins, and cortisol during the first 24 h after arrival. The first group did not undergo any manipulation. The second group (negative expectation) was told that severe headache would occur if SO2 dropped to less than 80% and their oximeters were set to display a saturation of 75%, even though real SO2 was much higher. The third group (negative expectation and social interaction) underwent the same ..