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We propose a symmetry-resolved entanglement for categorical non-invertible generalized symmetries (CaT-SREE) in (1+1)-dimensional CFTs. The definition parallels that of group-like invertible symmetries employing the concept of symmetric boundary states with respect to a categorical symmetry. Our examination extends to rational CFTs, where the behavior of CaT-SREE mirrors that of group-like invertible symmetries. This includes instances of the breakdown of entanglement equipartition at the next-to-leading order in the cutoff expansion. The findings shed light on the interplay between categorical symmetries, entanglement, and boundary conditions in (1 + 1)-dimensional CFTs., Comment: 6 pages + 3 pages appendix, 1 figure

A variational method for studying the ground state of strongly interacting quantum many-body bosonic systems is presented. Our approach constructs a class of extensive variational non-Gaussian wave functions which extend Gaussian states by means of nonlinear canonical transformations (NLCTs) on the fields of the theory under consideration. We illustrate this method with the one-dimensional Bose-Hubbard model for which the proposal presented here provides a family of approximate ground states at arbitrarily large values of the interaction strength. We find that, for different values of the interaction, the non-Gaussian NLCT-trial states sensibly improve the ground-state energy estimation when the system is in the Mott phase.

Characterizing the work statistics of driven complex quantum systems is generally challenging because of the exponential growth with the system size of the number of transitions involved between different energy levels. We consider the quantum work distribution associated with the driving of chaotic quantum systems described by random matrix Hamiltonians and characterize exactly the work statistics associated with a sudden quench for arbitrary temperature and system size. Knowledge of the work statistics yields the Loschmidt echo dynamics of an entangled state between two copies of the system of interest, the thermofield double state. This echo dynamics is dictated by the spectral form factor. We discuss its relation to frame potentials and its use to assess information scrambling.

Characterizing the work statistics of driven complex quantum systems is generally challenging because of the exponential growth with the system size of the number of transitions involved between different energy levels. We consider the quantum work distribution associated with the driving of chaotic quantum systems described by random matrix Hamiltonians and characterize exactly the work statistics associated with a sudden quench for arbitrary temperature and system size. Knowledge of the work statistics yields the Loschmidt echo dynamics of an entangled state between two copies of the system of interest, the thermofield double state. This echo dynamics is dictated by the spectral form factor. We discuss its relation to frame potentials and its use to assess information scrambling.

Using the path integral associated to a cMERA tensor network, we provide an operational definition for the complexity of a cMERA circuit/state which is relevant to investigate the complexity of states in quantum field theory. In this framework, it is possible to explicitly establish the correspondence (Minimal) Complexity $=$ (Least) Action. Remarkably, it is also shown how the cMERA complexity action functional can be seen as the action of a Liouville field theory, thus establishing a connection with two dimensional quantum gravity. Concretely, the Liouville mode is identified with the variational parameter defining the cMERA circuit. The rate of complexity growth along the cMERA renormalization group flow is obtained and shown to saturate limits which are in close resemblance to the fundamental bounds to the speed of evolution in unitary quantum dynamics, known as quantum speed limits. We also show that the complexity of a cMERA circuit measured through these complexity functionals, can be cast in terms of the variationally-optimized amount of left-right entanglement created along the cMERA renormalization flow. Our results suggest that the patterns of entanglement in states of a QFT could determine their dual gravitational descriptions through a principle of least complexity., Comment: 26 pages, improved presentation, new section on real time evolution, references added

Using the path integral associated to a cMERA tensor network, we provide an operational definition for the complexity of a cMERA circuit/state which is relevant to investigate the complexity of states in quantum field theory. In this framework, it is possible to explicitly establish the correspondence (Minimal) Complexity $=$ (Least) Action. Remarkably, it is also shown how the cMERA complexity action functional can be seen as the action of a Liouville field theory, thus establishing a connection with two dimensional quantum gravity. Concretely, the Liouville mode is identified with the variational parameter defining the cMERA circuit. The rate of complexity growth along the cMERA renormalization group flow is obtained and shown to saturate limits which are in close resemblance to the fundamental bounds to the speed of evolution in unitary quantum dynamics, known as quantum speed limits. We also show that the complexity of a cMERA circuit measured through these complexity functionals, can be cast in terms of the variationally-optimized amount of left-right entanglement created along the cMERA renormalization flow. Our results suggest that the patterns of entanglement in states of a QFT could determine their dual gravitational descriptions through a principle of least complexity., Comment: 26 pages, improved presentation, new section on real time evolution, references added

A universal relation is established between the quantum work probability distribution of an isolated driven quantum system and the Loschmidt echo dynamics of a two-mode squeezed state. When the initial density matrix is canonical, the Loschmidt echo of the purified double thermofield state provides a direct measure of information scrambling and can be related to the analytic continuation of the partition function. Information scrambling is then described by the quantum work statistics associated with the time-reversal operation on a single copy, associated with the sudden negation of the system Hamiltonian.

A universal relation is established between the quantum work probability distribution of an isolated driven quantum system and the Loschmidt echo dynamics of a two-mode squeezed state. When the initial density matrix is canonical, the Loschmidt echo of the purified double thermofield state provides a direct measure of information scrambling and can be related to the analytic continuation of the partition function. Information scrambling is then described by the quantum work statistics associated with the time-reversal operation on a single copy, associated with the sudden negation of the system Hamiltonian.

A universal relation is established between the quantum work probability distribution of an isolated driven quantum system and the Loschmidt echo dynamics of a two-mode squeezed state. When the initial density matrix is canonical, the Loschmidt echo of the purified double thermofield state provides a direct measure of information scrambling and can be related to the analytic continuation of the partition function. Information scrambling is then described by the quantum work statistics associated with the time-reversal operation on a single copy, associated with the sudden negation of the system Hamiltonian.

Quantum speed limits set an upper bound to the rate at which a quantum system can evolve and as such can be used to analyze the scrambling of information. To this end, we consider the survival probability of a thermofield double state under unitary time-evolution which is related to the analytic continuation of the partition function. We provide an exponential lower bound to the survival probability with a rate governed by the inverse of the energy fluctuations of the initial state. Further, we elucidate universal features of the non-exponential behavior at short and long times of evolution that follow from the analytic properties of the survival probability and its Fourier transform, both for systems with a continuous and a discrete energy spectrum. We find the spectral form factor in a number of illustrative models, notably we obtain the exact answer in the Gaussian unitary ensemble for any $N$ with excellent agreement with recent numerical studies. We also discuss the relationship of our findings to models of black hole information loss, such as the Sachdev-Ye-Kitaev model dual to AdS$_2$ as well as higher-dimensional versions of AdS/CFT., Comment: 33 pages, 6 figures, published version

Quantum speed limits set an upper bound to the rate at which a quantum system can evolve and as such can be used to analyze the scrambling of information. To this end, we consider the survival probability of a thermofield double state under unitary time-evolution which is related to the analytic continuation of the partition function. We provide an exponential lower bound to the survival probability with a rate governed by the inverse of the energy fluctuations of the initial state. Further, we elucidate universal features of the non-exponential behavior at short and long times of evolution that follow from the analytic properties of the survival probability and its Fourier transform, both for systems with a continuous and a discrete energy spectrum. We find the spectral form factor in a number of illustrative models, notably we obtain the exact answer in the Gaussian unitary ensemble for any $N$ with excellent agreement with recent numerical studies. We also discuss the relationship of our findings to models of black hole information loss, such as the Sachdev-Ye-Kitaev model dual to AdS$_2$ as well as higher-dimensional versions of AdS/CFT., Comment: 33 pages, 6 figures, published version

Los grupos de investigación en Física de la Atmósfera del Departmento de Física de la Universidad de Extremadura (UEx/AIRE) y del Instituto de Ciências da Terra de la Universidad de Évora (UE/ICT) constituyen un ejemplo de colaboración científica que se extiende a lo largo de más de 20 años. Estos grupos desarrollan estudios conjuntos relativos a la medida de la radiación solar y de sus principales factores moduladores, como son el ozono, la nubosidad y los aerosoles. Dicha colaboración está impulsada por la cercanía geográfica (apenas 100 km nos separan), la similitud en las líneas de investigación desarrolladas por dos grupos y la disposición de sendos grupos para la colaboración científica. Además, ha sido promovida con constancia por los líderes de los respectivos grupos: los Profesores Dres. José Agustín García García (UEx/AIRE) y Ana María Silva (UE/ICT). Así, para favorecer el trabajo conjunto, se ha producido un intercambio frecuente de investigadores de una institución a otra, mereciendo la pena destacar la realización de estancias breves de investigación de varios meses, becas PosDoc, proyectos conjuntos, participación en tribunales de Tesis Doctorales de personal de la otra institución, etc. Dicha colaboración se ha visto enriquecida por la participación adicional de la Estación de Sondeos Atmosféricos “El Arenosillo” perteneciente al Instituto Nacional de Técnica Aeroespacial (INTA/ESAt) que, además de ofrecer sus inmejorables instalaciones y equipamientos para la calibración de los radiómetros UV de banda ancha de las redes extremeña y alentejana, ha participado de forma activa en los proyectos de investigación conjuntos. Durante este periodo de colaboración se han abordado trabajos sobre diversos aspectos relacionados con la transferencia radiativa a través de la atmósfera, como estudios sobre el ozono y la nubosidad. Actualmente hay que destacar, de forma particular, los estudios conjuntos sobre aerosoles atmosféricos, campo en el que estos grupos est

A novel photovoltaic concentrator enables highly uniform irradiance on a small number of efficient solar cells. The maximum electrical power of a photovoltaic (PV) energy installation depends on three factors: the available irradiance, the size of the systems collecting sunlight, and the rate at which the device transforms light into electricity (the conversion efficiency). Developers can maximize the irradiance by carefully selecting the site and orientation of the solar facility. But they can only expand their sunlight collection systems for standard flat plate PV devices by increasing the number of solar cells, at greater cost. Here, we consider the advantages of an alternative PV system that produces more energy without increasing the number of cells used (actually, reducing it), by improving the conversion rates.We also present a new device that may enhance the commercial viability of such technologies.

A novel photovoltaic concentrator enables highly uniform irradiance on a small number of efficient solar cells. The maximum electrical power of a photovoltaic (PV) energy installation depends on three factors: the available irradiance, the size of the systems collecting sunlight, and the rate at which the device transforms light into electricity (the conversion efficiency). Developers can maximize the irradiance by carefully selecting the site and orientation of the solar facility. But they can only expand their sunlight collection systems for standard flat plate PV devices by increasing the number of solar cells, at greater cost. Here, we consider the advantages of an alternative PV system that produces more energy without increasing the number of cells used (actually, reducing it), by improving the conversion rates.We also present a new device that may enhance the commercial viability of such technologies.

Most cost-effective concentrated photovoltaics (CPV) systems are based on an optical train comprising two stages, the first being a Fresnel lens.

Most cost-effective concentrated photovoltaics (CPV) systems are based on an optical train comprising two stages, the first being a Fresnel lens.

Address-Event-Representation (AER) is a communication protocol for transferring asynchronous events between VLSI chips, originally developed for neuro-inspired processing systems (for example, image processing). Such systems may consist of a complicated hierarchical structure with many chips that transmit data among them in real time, while performing some processing (for example, convolutions). The information transmitted is a sequence of spikes coded using high speed digital buses. These multi-layer and multi-chip AER systems perform actually not only image processing, but also audio processing, filtering, learning, locomotion, etc. This paper present an AER interface for controlling an anthropomorphic robotic hand with a neuro-inspired system.

Address-Event-Representation (AER) is a communication protocol for transferring asynchronous events between VLSI chips, originally developed for neuro-inspired processing systems (for example, image processing). Such systems may consist of a complicated hierarchical structure with many chips that transmit data among them in real time, while performing some processing (for example, convolutions). The information transmitted is a sequence of spikes coded using high speed digital buses. These multi-layer and multi-chip AER systems perform actually not only image processing, but also audio processing, filtering, learning, locomotion, etc. This paper present an AER interface for controlling an anthropomorphic robotic hand with a neuro-inspired system.

Address-Event-Representation (AER) is a communication protocol for transferring asynchronous events between VLSI chips, originally developed for neuro-inspired processing systems (for example, image processing). Such systems may consist of a complicated hierarchical structure with many chips that transmit data among them in real time, while performing some processing (for example, convolutions). The information transmitted is a sequence of spikes coded using high speed digital buses. These multi-layer and multi-chip AER systems perform actually not only image processing, but also audio processing, filtering, learning, locomotion, etc. This paper present an AER interface for controlling an anthropomorphic robotic hand with a neuro-inspired system.

Address-Event-Representation (AER) is a communication protocol for transferring asynchronous events between VLSI chips, originally developed for neuro-inspired processing systems (for example, image processing). Such systems may consist of a complicated hierarchical structure with many chips that transmit data among them in real time, while performing some processing (for example, convolutions). The information transmitted is a sequence of spikes coded using high speed digital buses. These multi-layer and multi-chip AER systems perform actually not only image processing, but also audio processing, filtering, learning, locomotion, etc. This paper present an AER interface for controlling an anthropomorphic robotic hand with a neuro-inspired system.

Address-Event-Representation (AER) is a communication protocol for transferring asynchronous events between VLSI chips, originally developed for neuro-inspired processing systems (for example, image processing). Such systems may consist of a complicated hierarchical structure with many chips that transmit data among them in real time, while performing some processing (for example, convolutions). The information transmitted is a sequence of spikes coded using high speed digital buses. These multi-layer and multi-chip AER systems perform actually not only image processing, but also audio processing, filtering, learning, locomotion, etc. This paper present an AER interface for controlling an anthropomorphic robotic hand with a neuro-inspired system.

[ES] Aproximación a la evolución paleoecológica durante el periodo Tardiglariar y postglaciar de dos puntos de Pirineo y la Depresión del Ebro mediante la correlación de depósitos de distin origen: Llauset (depósito lacustre) y Parco (depósito detrítico en cueva)., [EN] This paper considers palaeoecological evolution during the Late Glacial and Postglacial periods at two sites in the Pyrenees and the Ebro Basin: Llauset (a lacustrine deposit) and Parco ( a detritical deposit in a cave) by means of the comparison of their different sedimentary formations.

[ES] El objeto de nuestro trabajo es el estudio del micromodelado desarrollado sobre granito y su evolución postglacial en dos áreas de los Pirineos Españoles: Panticosa (valle del río Gállego) y Cavallers (valle del río Koguera de Tor). Ambas áreas presentan un modelado principalmente glacial con micro y macro-formas típicas, heredadas de la Última glaciación., [EN] The aim our work is the study of micromodelate developed over granite their postglacial and present evolution in two areas of Spanish Pyrennees, Panticosa (Gállego Valley), and Cavallers (Noguera de Ter Valley).