Collective intelligence: aggregation of information from neighbors in a guessing game

Complex systems show the capacity to aggregate information and to display coordinated activity. In the case of social systems the interaction of different individuals leads to the emergence of norms, trends in political positions, opinions, cultural traits, and even scientific progress. Examples of collective behavior can be observed in activities like the Wikipedia and Linux, where individuals aggregate their knowledge for the benefit of the community, and citizen science, where the potential of collectives to solve complex problems is exploited. Here, we conducted an online experiment to investigate the performance of a collective when solving a guessing problem in which each actor is endowed with partial information and placed as the nodes of an interaction network. We measure the performance of the collective in terms of the temporal evolution of the accuracy, finding no statistical difference in the performance for two classes of networks, regular lattices and random networks. We also determine that a Bayesian description captures the behavior pattern the individuals follow in aggregating information from neighbors to make decisions. In comparison with other simple decision models, the strategy followed by the players reveals a suboptimal performance of the collective. Our contribution provides the basis for the micro-macro connection between individual based descriptions and collective phenomena.Comment: 9 pages, 9 figure

Crowd synchrony and quorum sensing in delay-coupled lasers

Crowd synchrony and quorum sensing arise when a large number of dynamical elements communicate with each other via a common information pool. Previous evidence in different fields, including chemistry, biology and civil engineering, has shown that this type of coupling leads to synchronization, when coupling is instantaneous and the number of coupled elements is large enough. Here we consider a situation in which the transmission of information between the system components and the coupling pool is not instantaneous. To that end, we model a system of semiconductor lasers optically coupled to a central laser with a delay. Our results show that, even though the lasers are non-identical due to their distinct optical frequencies, zero-lag synchronization arises. By changing a system parameter, we can switch between two different types of synchronization transition. The dependence of the transition with respect to the delay-coupling parameters is studied.Comment: 4 pages, 4 figure

Extreme intensity pulses in a semiconductor laser with a short external cavity

We present a numerical study of the pulses displayed by a semiconductor laser with optical feedback in the short cavity regime, such that the external cavity round trip time is smaller than the laser relaxation oscillation period. For certain parameters there are occasional pulses, which are high enough to be considered extreme events. We characterize the bifurcation scenario that gives rise to such extreme pulses and study the influence of noise. We demonstrate intermittency when the extreme pulses appear and hysteresis when the attractor that sustains these pulses is destroyed. We also show that this scenario is robust under the inclusion of noise

Relation between quantum advantage in supervised learning and quantum computational advantage

The widespread use of machine learning has raised the question of quantum supremacy for supervised learning as compared to quantum computational advantage. In fact, a recent work shows that computational and learning advantage are, in general, not equivalent, i.e., the additional information provided by a training set can reduce the hardness of some problems. This paper investigates under which conditions they are found to be equivalent or, at least, highly related. The existence of efficient algorithms to generate training sets emerges as the cornerstone of such conditions. These results are applied to prove that there is a quantum speed-up for some learning tasks based on the prime factorization problem, assuming the classical intractability of this problem

Quantum multiple hypothesis testing based on a sequential discarding scheme

We consider the quantum multiple hypothesis testing problem, focusing on the case of hypothesis represented by pure states. A sequential adaptive algorithm is derived and analyzed first. This strategy exhibits a decay rate in the error probability with respect to the expected value of measurements greater than the optimal decay rate of the fixed-length methods. A more elaborated scheme is developed next, by serially concatenating multiple implementations of the first scheme. In this case each stage considers as a priori hypothesis probability the a posteriori probability of the previous stage. We show that, by means of a fixed number of concatenations, the expected value of measurements to be performed decreases considerably. We also analyze one strategy based on an asymptotically large concatenation of the initial scheme, demonstrating that the expected number of measurements in this case is upper bounded by a constant, even in the case of zero average error probability. A lower bound for the expected number of measurements in the zero error probability setting is also derived.This work was supported in part by the Agencia Estatal de Investigación, Ministerio de Ciencia e Innovación, of the Spanish Government, under Grant RED2018-102668-T and Grant PID2019-104958RB-C41; in part by the Catalan Government under Grant 2017 SGR 578 AGAUR; and in part by the QuantumCAT within the European Regional Development Fund (ERDF) Program of Catalunya under Grant 001-P-001644.Postprint (published version

Controlling the likelihood of rogue waves in an optically injected semiconductor laser via direct current modulation

Extreme and rare events are nowadays the object of intensive research. Rogue waves are extreme waves that appear suddenly in many natural systems, even in apparently calm situations. Here we study numerically the rogue wave dynamics in an optically injected semiconductor laser with external periodic forcing that is implemented via direct modulation of the laser pump current. In the region of optical injection parameters where the laser intensity is chaotic and occasional ultrahigh pulses occur, our aim is to control the system by applying a weak modulation. We find that for an adequate range of frequency and amplitude parameters, the modulation can completely suppress the extreme pulses. We also show that the interplay between modulation and an external source of noise can significantly modify their probability of occurrence. These results can motivate a range of experimental and theoretical investigations in other natural systems.Peer ReviewedPostprint (published version

Prediction of riboflavin and ascorbic acid concentrations in skimmed heat-treated milk using front-face fluorescence spectroscopy

Altres ajuts: Acord transformatiu CRUE-CSICThe objective of this work was to obtain degradation kinetic models of riboflavin and ascorbic acid, and to evaluate the potential of front-face fluorescence (FFF) spectroscopy to predict their concentration in milk after thermal processing. A factorial design with three temperatures (70, 80 and 90 °C) and nine times (from 0 to 60 min) of heat treatment was used. Degradation kinetics of both vitamins were of first order. Predictive kinetic models using the Arrhenius equation had a variability coefficient of 2.26 and 3.64% for riboflavin and ascorbic acid, respectively. With fluorescent predictors such as tryptophan, Maillard compounds and riboflavin, prediction models with coefficients of variation smaller than 3.57% for riboflavin and ranging from 4.24 to 14.25% for ascorbic acid were obtained. In conclusion, FFF is a viable alternative to predict riboflavin and ascorbic acid content of milk which could allow in-line monitoring and control of thermal damage

Aproximación a los paisajes culturales del regadío. La Geria de Lanzarote

[EN] La Geria of Lanzarote explains - to our knowledge - the agriculture as a smart way to working the land. The geometry of "small volcanoes" built by hand, causes the rocks to protect from the perennial Trade Winds the few malmsey vines hidden in each crater, which are covered with “picón” (term use in the island for volcanic lapilli). Only then, the vines can pick up the slight spray of the Atlantic, allowing the roots through the thin layers of lava to reach the most solvent clay soils, and avoid in this process the evapotranspiration. Is notoriously photogenic the space achieved, as well as the ability to produce a single system - almost in a single gesture – a landscape as unusual as it is appropriate, which gives special identity and characterizes the island. La Geria is the epitome of the island agricultural architecture, example of perfect integration between man and nature, and an original sample of the sanding technique with which the vast majority of the island's surface is cultivated. Therefore, man in his struggle for survival in a hostile environment such as Lanzarote, shows how to construct settings charged with humanity, dissipating less energy and participating, in turn, in the aesthetic and emotional character of the island environments.[ES] La Geria de Lanzarote explica –a nuestro entender– la agricultura como el trabajo inteligente de la tierra. La geometría de “pequeños volcanes”, construida con las manos, hace que las rocas protejan de los Alisios perennes las tres escasas cepas de malvasía escondidas en cada cráter, recubierto de “picón”, el lapilli volcánico. Sólo así pueden recoger el leve rocío del Atlántico, que permite a las raíces atravesar las capas ligeras de las lavas y alcanzar los suelos arcillosos más solventes y evitar, de paso, la evotranspiración. Es notoria la fotogenia del espacio conseguido, tanto como la capacidad para producir con un solo sistema – casi un solo gesto – un paisaje tan propio como insólito, que le confiere especial identidad y caracteriza la isla. La Geria es el máximo exponente de la arquitectura agrícola insular, ejemplo de perfecta integración entre el hombre y la naturaleza, y muestra original de la técnica del enarenado con la que se cultiva la mayor parte de la superficie insular. Así, el hombre, en su lucha por la supervivencia en un ambiente tan hostil como Lanzarote, muestra cómo construir entornos cargados de humanidad disipando la menor energía y participando, a su vez, del carácter estético y emocional de la isla.Sardà Ferran, J.; Zamora Cabrera, A. (2015). Aproximación a los paisajes culturales del regadío. La Geria de Lanzarote. En Irrigation, Society and Landscape. Tribute to Tom F. Glick. Editorial Universitat Politècnica de València. 845-855. https://doi.org/10.4995/ISL2014.2014.197OCS84585

Rapid quantification of riboflavin in milk by front-face fluorescence spectroscopy : a preliminary study

The front-face fluorescence spectroscopy technique was used to establish a rapid prediction model of riboflavin concentration in milk without prior sample preparation. The prediction model developed was then compared with two conventional high performance liquid chromatography (HPLC)-based quantification methods. The method of standard addition allowed detecting a linear correlation between fluorescence intensity and riboflavin concentration in 12% (w/w) reconstituted low-heat milk powder. Validation of the model yielded an R2 of 0.99 with a standard error of prediction of 0.13 mg/L. The results suggest a potential use of front-face fluorescence spectroscopy as a simple method for off- and in-line determinations of riboflavin in milk