Many phenomena in solid-state physics can be understood in terms of their topological properties. Recently, controlled protocols of quantum walk (QW) are proving to be effective simulators of such ...phenomena. Here we report the realization of a photonic QW showing both the trivial and the non-trivial topologies associated with chiral symmetry in one-dimensional (1D) periodic systems. We find that the probability distribution moments of the walker position after many steps can be used as direct indicators of the topological quantum transition: while varying a control parameter that defines the system phase, these moments exhibit a slope discontinuity at the transition point. Numerical simulations strongly support the conjecture that these features are general of 1D topological systems. Extending this approach to higher dimensions, different topological classes, and other typologies of quantum phases may offer general instruments for investigating and experimentally detecting quantum transitions in such complex systems.
The article deals with the essay “Inattualità di Dioniso” written by Furio Jesi as an introduction to the Italian translation of the volume Dionysos. Histoire du culte de Bacchus, by Henri Jeanmaire ...(Einaudi, 1972). The article places and discusses Jesi’s text in the context of studies on Dionysus of the second half of the twentieth century. The analysis focuses on the Jesian conception of the conception of “Dionysian” as a category still looming in the intellectual debate.
•A Gaussian process (GP) model is trained to predict the zone temperature in a building.•The prediction error of the GP is compared to a physics-based grey-box model.•The GP presented a high error ...when faced with data values out of the training range.•Adaptive training is applied to the GP, reducing the prediction error in up to 50%.
This paper analyzes the suitability of Gaussian processes for thermal building modelling by comparing the day-ahead prediction error of the internal air temperature with a grey-box model. The reference building is a single-zone office with a hydronic heating system, modelled in TRNSYS and simulated during the winter and spring periods. Using the output data of the reference building, the parameters of a Gaussian process and of a physics-based grey-box model are identified, with training periods ranging from three days to six weeks. After three weeks of training, the Gaussian processes achieve 27% lower prediction errors during occupied times compared to the grey-box model. During unoccupied times, however, the Gaussian processes perform consistently worse than the grey-box model. This is due to their large generalization error, especially when faced with untrained ambient temperature values. To reduce the impact of changing weather conditions, adaptive training is applied to the Gaussian processes. When re-training the models every 24h, the prediction error is reduced over 21% during unoccupied times and over 10% during occupied times compared to the non-adaptive training case. These results show that the proposed Gaussian process model can correctly describe a building's thermal dynamics. However, in its current form the model is limited to applications where the prediction during occupied times is more relevant.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•A modelling method that combines grey-box and Gaussian process models is presented.•In addition to the hybrid model, pure grey-box and Gaussian process models are also developed.•All models are ...trained adaptively with varying training period lengths.•The accuracy of the models’ day-ahead air temperature and energy consumption prediction is compared.•The hybrid model achieves the best predictions in all cases.
This paper presents a hybrid building modelling method with a reduced modelling and calibration effort. The method combines a physics-based model, which describes the general behaviour of the system, with a machine learning algorithm trained to correct the physics-based model’s systematic errors. To exemplify the method, a highly simplified grey-box model is used as the physics-based part and a Gaussian process as the machine learning part. It is shown that the hybrid model improves the temperature and energy predictions of the grey-box model while having a lower generalization error than the pure Gaussian process. Specifically, the hybrid approach achieved a day-ahead zone temperature prediction error ca. 0.1 K (RMSE) lower than the grey-box model. As for the energy prediction, the hybrid model obtained an error of 3% compared to 8% for the grey-box model. In comparison to the Gaussian process, the hybrid approach achieved better predictions in all cases. The improvements were especially high when the models were trained with small datasets: 0.7 K in the temperature prediction and 25 percentage points in the energy prediction.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The article aims to analyze some historiographical and methodological aspects of the study of polytheisms in Late Antiquity. Recent research has somewhat neglected the internal mechanisms of late ...antique polytheisms. Interpreted simply as residual in an Empire watching the “triumph of Christianity”, studies have continued to project on the polytheistic cults of the fourth and fifth centuries CE the new conception of religion that Christian authors were constructing as an autonomous sphere from the political and social life of the ancient city. Against this backdrop, we focus on some historiographical tendencies that have contributed to the interpretation of late antique polytheisms. Such tendencies include the alleged spread of a soteriological anxiety due to the crises that would have crossed the empire, the individualization of religious practices, the spiritualization of the cult, and the ritualization of philosophical activity. The analysis of the different cases encourages a change of paradigm, which takes into account the plurality of rites, agents, and historical contexts without homologizing them all into an alleged “paganism” that would have eventually been defeated by Christianity.
Understanding the effects of environmental change on ecosystems requires the identification of baselines that may act as reference conditions. However, the continuous change of these references ...challenges our ability to define the true natural status of ecosystems. The so-called sliding baseline syndrome can be overcome through the analysis of quantitative time series, which are, however, extremely rare. Here we show how combining historical quantitative data with descriptive 'naturalistic' information arranged in a chronological chain allows highlighting long-term trends and can be used to inform present conservation schemes. We analysed the long-term change of a coralligenous reef, a marine habitat endemic to the Mediterranean Sea. The coralligenous assemblages of Mesco Reef (Ligurian Sea, NW Mediterranean) have been studied, although discontinuously, since 1937 thus making available both detailed descriptive information and scanty quantitative data: while the former was useful to understand the natural history of the ecosystem, the analysis of the latter was of paramount importance to provide a formal measure of change over time. Epibenthic assemblages remained comparatively stable until the 1990s, when species replacement, invasion by alien algae, and biotic homogenisation occurred within few years, leading to a new and completely different ecosystem state. The shift experienced by the coralligenous assemblages of Mesco Reef was probably induced by a combination of seawater warming and local human pressures, the latter mainly resulting in increased water turbidity; in turn, cumulative stress may have favoured the establishment of alien species. This study showed that the combined analysis of quantitative and descriptive historical data represent a precious knowledge to understand ecosystem trends over time and provide help to identify baselines for ecological management.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•Flexible office spaces can be enabled by selecting an appropriate control zoning strategy for the HVAC system.•Radiant ceilings and thermally-active buildings systems are robust solutions for ...flexible office spaces.•Mechanical ventilation is more sensitive to space layout changes, and thus requires more complex control strategies to ensure thermal comfort.
In office buildings, the space layout usually needs to be repeatedly redesigned in order to meet tenants’ requirements during the building's life cycle. In this study, the effect of a flexible space layout design on thermal comfort and energy demand is investigated in a modern open-plan office space. Using dynamic thermal simulation, the applicability of three different HVAC systems (mechanical ventilation, radiant ceiling and a thermally-active building system) combined with four control zoning strategies are assessed. Finding a robust solution for each configuration and control strategy can support design decisions during the design planning or interior renovation phase. The main objective is to enable a flexible space layout design during the complete building life cycle without compromising on thermal comfort or energy efficiency.
The results show that radiant ceilings and thermally-active building systems are promising solutions for flexible office spaces in the location of Stuttgart, whereas mechanical ventilation systems require a more complex control strategy to ensure thermal comfort. Connecting the field of building controls with parametric building modeling enables flexible space layout designs to be assessed with different HVAC systems.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The study of causal relations has recently been applied to the quantum realm, leading to the discovery that not all physical processes have a definite causal structure. While indefinite causal ...processes have previously been experimentally shown, these proofs relied on the quantum description of the experiments. Yet, the same experimental data could also be compatible with definite causal structures within different descriptions. Here, we present the first demonstration of indefinite temporal order outside of quantum formalism. We show that our experimental outcomes are incompatible with a class of generalised probabilistic theories satisfying the assumptions of locality and definite temporal order. To this end, we derive physical constraints (in the form of a Bell-like inequality) on experimental outcomes within such a class of theories. We then experimentally invalidate these theories by violating the inequality using entangled temporal order. This provides experimental evidence that there exist correlations in nature which are incompatible with the assumptions of locality and definite temporal order.
This book fills a gap in the study of mystery cults in Graeco-Roman Antiquity. Focusing on the visual language surrounding these cults, it aims to understand how images depict mysteries in different ...cults: Dionysus, Mithras, Mother of the Gods, and Isiac cults.
The effect of the Earth's gravitational potential on a quantum wave function has only been observed for massive particles. In this paper we present a scheme to measure a gravitationally induced phase ...shift on a single photon traveling in a coherent superposition along different paths of an optical fiber interferometer. To create a measurable signal for the interaction between the static gravitational potential and the wave function of the photon, we propose a variant of a conventional Mach-Zehnder interferometer. We show that the predicted relative phase difference of 10−5 rad is measurable even in the presence of fiber noise, provided additional stabilization techniques are implemented for each arm of a large-scale fiber interferometer. Effects arising from the rotation of the Earth and the material properties of the fibers are analysed. We conclude that optical fiber interferometry is a feasible way to measure the gravitationally induced phase shift on a single-photon wave function, and thus provides a means to corroborate the equivalence of the energy of the photon and its effective gravitational mass.
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