Desinformación en Internet y hegemonía en redes sociales

El acceso sin control, el anonimato y la falta de regulación para publicar en Internet; causa que los contenidos disponibles en esta red muchas veces carezcan de rigurosidad, confiabilidad y credibilidad; lo que genera más desinformación que la construcción de una inteligencia colectiva. Además, el ciberespacio representa un nuevo espacio público para interacciones directas sin restricciones de tiempo ni espacio, siendo las redes sociales la mayor expresión de este fenómeno. En ellas la dinámica de grupos y la comunicación interpersonal se manifiesta de manera similar a los grupos sociales en el mundo físico, generándose también relaciones de poder, emergencia de líderes, jerarquización de los miembros y monopolización de las opiniones. Para enfrentar ambas realidades es necesario que las personas desarrollen; por un lado, una actitud crítica para analizar contenidos mientras que; por otro, estimulen una participación activa en las redes sociales para evitar la hegemonía

El desarrollo tecnológico en los próximos pasos para la colonización del espacio

La exploración espacial es liderada en la actualidad por EE.UU.; sin embargo, tanto Rusia, Japón y la Comunidad Europea, así como China, India y Brasil han intensificado sus respectivos programas espaciales para incorporarse a estos esfuerzos. De acuerdo a los planes de las principales agencias espaciales del mundo, se puede señalar que el desarrollo de la capacidad espacial internacional en su conjunto, permitirá que antes del año 2020 una sonda visite y regrese de un asteroide, entre los años 2020 y 2030 se instale una base habitada en la luna y entre el 2030 y el 2050 se instale otra en Marte o en alguna de sus lunas. El propósito de este ensayo es dar a conocer, resumidamente, la visión científica respecto de cual será el desarrollo tecnológico requerido y las fases necesarias para cumplir con lo anterior

Enhanced Efficiency at Maximum Power in a Fock-Darwin Model Quantum Dot Engine

We study the performance of an endoreversible magnetic Otto cycle with a working substance composed of a single quantum dot described using the well-known Fock-Darwin model. We find that tuning the intensity of the parabolic trap (geometrical confinement) impacts the proposed cycle's performance, quantified by the power, work, efficiency, and parameter region where the cycle operates as an engine. We demonstrate that a parameter region exists where the efficiency at maximum output power exceeds the Curzon-Ahlborn efficiency, the efficiency at maximum power achieved by a classical working substance.Comment: 14 pages, 7 figure

Digital-analog quantum computing of fermion-boson models in superconducting circuits

We propose a digital-analog quantum algorithm for simulating the Hubbard-Holstein model, describing strongly-correlated fermion-boson interactions, in a suitable architecture with superconducting circuits. It comprises a linear chain of qubits connected by resonators, emulating electron-electron (e-e) and electron-phonon (e-p) interactions, as well as fermion tunneling. Our approach is adequate for a digital-analog quantum computing (DAQC) of fermion-boson models including those described by the Hubbard-Holstein model. We show the reduction in the circuit depth of the DAQC algorithm, a sequence of digital steps and analog blocks, outperforming the purely digital approach. We exemplify the quantum simulation of a half-filling two-site Hubbard-Holstein model. In such example we obtain fidelities larger than 0.98, showing that our proposal is suitable to study the dynamical behavior of solid-state systems. Our proposal opens the door to computing complex systems for chemistry, materials, and high-energy physics.Comment: 6+5 Pages, 5+2 Figures, 1 Tabl

Adaptive random quantum eigensolver

We propose an adaptive random quantum algorithm to obtain an optimized eigensolver. Specifically, we introduce a general method to parametrize and optimize the probability density function of a random number generator, which is the core of stochastic algorithms. We follow a bioinspired evolutionary mutation method to introduce changes in the involved matrices. Our optimization is based on two figures of merit: learning speed and learning accuracy. This method provides high fidelities for the searched eigenvectors and faster convergence on the way to quantum advantage with current noisy intermediate-scaled quantum computers.Junta de Andalucía (Grants No. P20-00617 and No. US-1380840)Science and Technology Commission of Shanghai Municipality (Grant No. 2019SHZDZX01-ZX04

Analog Quantum Approximate Optimization Algorithm

We present an analog version of the quantum approximate optimization algorithm suitable for current quantum annealers. The central idea of this algorithm is to optimize the schedule function, which defines the adiabatic evolution. It is achieved by choosing a suitable parametrization of the schedule function based on interpolation methods for a fixed time. This algorithm provides an approximate result of optimization problems that may be developed during the coherence time of current quantum annealers on their way towards quantum advantage.Comment: 5 pages, 4 figure

Superconducting circuit architecture for digital-analog quantum computing

[EN] We propose a superconducting circuit architecture suitable for digital-analog quantum computing (DAQC) based on an enhanced NISQ family of nearest-neighbor interactions. DAQC makes a smart use of digital steps (single qubit rotations) and analog blocks (parametrized multiqubit operations) to outperform digital quantum computing algorithms. Our design comprises a chain of superconducting charge qubits coupled by superconducting quantum interference devices (SQUIDs). Using magnetic flux control, we can activate/deactivate exchange interactions, double excitation/de-excitations, and others. As a paradigmatic example, we present an efficient simulation of an l x h fermion lattice (with 2 < l <= h), using only 2(2l + 1)(2) + 24 analog blocks. The proposed architecture design is feasible in current experimental setups for quantum computing with superconducting circuits, opening the door to useful quantum advantage with fewer resources.The authors acknowledge support from Spanish MCIU/AEI/FEDER (PGC2018-095113-B-I00), Basque Government IT98616, projects QMiCS (820505) and OpenSuperQ (820363) of EU Flagship on Quantum Technologies, EU FET Open Grants Quromorphic and EPIQUS, Shanghai STCSM (Grant No. 2019SHZDZX01-ZX04), Chilean Government Financiamiento Basal para Centros Cientificos y Tecnologicos de Excelencia (Grant No. AFB180001) and Proyecto AP_539SF, DICYT (USA-2055 Dicyt), Universidad de Santiago de Chile

Late Cretaceous – early Eocene counterclockwise rotation of the Fueguian Andes and evolution of the Patagonia-Antarctic Peninsula system

International audienceThe southernmost Andes of Patagonia and Tierra del Fuego present a prominent arc-shaped structure: the Patagonian Bend. Whether the bending is a primary curvature or an orocline is still matter of controversy. New paleomagnetic data have been obtained south of the Beagle Channel in 39 out of 61 sites. They have been drilled in Late Jurassic and Early Cretaceous sediments and interbedded volcanics and in mid-Cretaceous to Eocene intrusives of the Fuegian Batholith. The anisotropy of magnetic susceptibility was measured at each site and the influence of magnetic fabric on the characteristic remanent magnetizations (ChRM) in plutonic rocks was corrected using inverse tensors of anisotropy of remanent magnetizations. Normal polarity secondary magnetizations with west-directed declination were obtained in the sediments and they did not pass the fold test. Thesecharacteristic directions are similar to those recorded by mid Cretaceous intrusivessuggesting a remagnetization event during the normal Cretaceous superchron and describea large (>90°) counterclockwise rotation. Late Cretaceous to Eocene rocks of the FueguianBatholith, record decreasing counterclockwise rotations of 45° to 30°. These paleomagneticresults are interpreted as evidence of a large counterclockwise rotation of the FueguianAndes related to the closure of the Rocas Verdes Basin and the formation of the DarwinCordillera during the Late Cretaceous and Paleocene.The tectonic evolution of the Patagonian Bend can thus be described as theformation of a progressive arc from an oroclinal stage during the closure of the RocasVerdes basin to a mainly primary arc during the final stages of deformation of theMagallanes fold and thrust belt. Plate reconstructions show that the Antarctic Peninsulawould have formed a continuous margin with Patagonia between the Early Cretaceous andthe Eocene, and acted as a non-rotational rigid block facilitating the development of thePatagonian Bend

Portfolio optimization with digitized counterdiabatic quantum algorithms

We consider digitized-counterdiabatic quantum computing as an advanced paradigm to approach quantum advantage for industrial applications in the NISQ era. We apply this concept to investigate a discrete meanvariance portfolio optimization problem, showing its usefulness in a key finance application. Our analysis shows a drastic improvement in the success probabilities of the resulting digital quantum algorithm when approximate counterdiabatic techniques are introduced. Along these lines, we discuss the enhanced performance of our methods over variational quantum algorithms like QAOA and DC-QAOA.This work is supported by NSFC (Grant No. 12075145) , STCSM (Grant No. 2019SHZDZX01-ZX04) , EU FET Open Grant EPIQUS (No. 899368) , QUANTEK project (Grant No. KK-2021/00070) , the Basque Government through Grant No. IT1470-22, the project Grant No. PID2021-126273NB-I00 funded by MCIN/AEI/10.13039/501100011033 and by ERDF A way of making Europe and ERDF Invest in your Future and the Ramon y Cajal program (Grant No. RYC-2017-22482) . F. A. -A. acknowledges ANID Subvencion a la Instalacion en la Academia SA77210018 ANID Proyecto Basal AFB 180001. Authors would also like to acknowledge the Azure quantum credits program for providing access to the Quantinuum H1 emulator