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Note Illustrative della Carta geologica d'Italia alla scala 1:50.000, F. 121 Brescia
No full text<p>Note illustrative redatte per il Foglio geologico n. 121 Brescia della Carta Geologica d'Italia alla scala 1:50.000. 304 pp.</p>
Geological and engineering heritage of Lungro rock salt (Calabria, Italy)
Full text link<p>Nearby the municipality of Lungro (Calabria) is the longest-running Italian rock salt mine, exploited almost continuously from antiquity until 1978. The mining activity is recorded since the Middle Ages, although archaeological studies suggest that salt production by near-surface excavation dates to the Greek and Roman civilization or even to prehistoric times. During the Middle Ages, mining methods pointed to the maximum profit, and the salt deposit, rather than being rationally mined, was exploited vertically, following the winding path of high-quality salt layers. This approach led to troubles such as rock instability, inadequate ventilation and water infiltration, that characterised the site up to its recent abandonment. Although the mine was partially renovated at the end of the 19th century, both in its structure and work organization, a steep decline began.<br>\nEasy access to the underground works was never solved: still in the 1970’s, two of the eight working hours of each daily shift were spent reaching the workplace, as there were over 2000 steps to walk. Poor mining methods persisted throughout the 20th century, leading to its abandonment in 1978.</p>
Higher Structure of Chiral Symmetry
No full textA recent development in our understanding of the theory of quantum fields is the fact that familiar gauge theories in spacetime dimensions greater than two can have non-invertible symmetries generated by topological defects. The hallmark of these non-invertible symmetries is that the fusion rule deviates from the usual group-like structure, and in particular the fusion coefficients take values in topological field theories (TFTs) rather than in mere numbers. In this paper we begin an exploration of the associativity structure of non-invertible symmetries in higher dimensions. The first layer of associativity is captured by F-symbols, which we find to assume values in TFTs that have one dimension lower than that of the defect. We undertake an explicit analysis of the F-symbols for the non-invertible chiral symmetry that is preserved by the massless QED and explore their physical implications. In particular, we show the F-symbol TFTs can be detected by probing the correlators of topological defects with 't Hooft lines. Furthermore, we derive the Ward–Takahashi identity that arises from the chiral symmetry on a large class of four-dimensional manifolds with non-trivial topologies directly from the topological data of the symmetry defects, without referring to a Lagrangian formulation of the theory
Burnt-Areas-Italian-Terrestrial-Ecosystem (2018-2024)
No full text<p>Il prodotto di mappatura BA-ITE descrive le aree percorse da incendio identificate da EFFIS nel corso dell’anno solare (1° gennaio – 31 dicembre) sul territorio nazionale.<br>Le coperture forestali di riferimento derivano dal modello ECM-F4_2020 (https://groupware.sinanet.isprambiente.it/prodotti-operativi-di-sorveglianza-ambientale/library/ecosystems-classification-model), classificate secondo la nomenclatura EUNIS (2021) nei principali tipi forestali (T1 latifoglie decidue, T2 sempreverdi, T3 conifere, T34 temperate sub-alpine, TNC non classificate).<br>I dati spaziali sono forniti in formato vettoriale e riproiettati in un sistema di coordinate metrico decimale uniforme.<br>L’intersezione tra poligoni EFFIS e classi forestali ECM-F4 è stata analizzata con strumenti GIS, mentre le elaborazioni geostatistiche sono state realizzate in Python mediante GeoPandas e Rasterstats.</p>
Note Illustrative della Carta geomorfologica d'Italia alla scala 1:50.000, F. 353 Montalto di Castro
No full text<p>Note illustrative redatte per il Foglio geomorfologico n. 353 Montalto di Castro della Carta Geomorfologica d'Italia alla scala 1:50.000. 218 pp.</p>
Rescuing the Unruh effect in Lorentz violating gravity
No full textWhile the robustness of Hawking radiation in the presence of UV Lorentz breaking is well-established, the Unruh effect has posed a challenge, with a large literature concluding that even the low-energy restoration of Lorentz invariance may not be sufficient to sustain this phenomenon. Notably, these previous studies have primarily focused on Lorentz-breaking matter on a conventional Rindler wedge. In this work, we demonstrate that considering the complete structure of Lorentz-breaking gravity, specifically the presence of a hypersurface orthogonal æther field, leads to the selection of a new Rindler wedge configuration characterized by a uniformly accelerated æther flow. This uniform acceleration provides a reference scale for comparison with the Lorentz-breaking one, thus ensuring the persistence of the Unruh effect in this context. We establish this by calculating the expected temperature using a Bogolubov approach, and by analyzing the response of a uniformly accelerated detector. We suggest that this resilience of the Unruh effect opens interesting possibilities towards future developments for using it as a tool to constrain Lorentz breaking theories of gravity
The Principle of Maximum Conformality Correctly Resolves the Renormalization-Scheme-Dependence Problem
No full textIn this paper, we clarify a serious misinterpretation and consequent misuse of the Principle of Maximum Conformality (PMC), which also can serve as a mini-review of PMC. In a recently published article, P. M. Stevenson has claimed that "the PMC is ineffective and does nothing to resolve the renormalization-scheme-dependence problem", concluding incorrectly that the success of PMC predictions is due to the PMC being a "laborious, ad hoc, and back-door" version of the Principle of Minimal Sensitivity (PMS). We show that such conclusions are incorrect, deriving from a misinterpretation of the PMC and an overestimation of the applicability of the PMS. The purpose of the PMC is to achieve precise fixed-order pQCD predictions, free from conventional renormalization schemes and scale ambiguities. We demonstrate that the PMC predictions satisfy all the self-consistency conditions of the renormalization group and standard renormalization-group invariance; the PMC predictions are thus independent of any initial choice of renormalization scheme and scale. The scheme independence of the PMC is also ensured by commensurate scale relations, which relate different observables to each other. Moreover, in the Abelian limit, the PMC dovetails into the well-known Gell-Mann–Low framework, a method universally revered for its precision in QED calculations. Due to the elimination of factorially divergent renormalon terms, the PMC series not only attains a convergence behavior far superior to that of its conventional counterparts but also deftly curtails any residual scale dependence caused by the unknown higher-order terms. This refined convergence, coupled with its robust suppression of residual uncertainties, furnishes a sound and reliable foundation for estimating the contributions from unknown higher-order terms. Anchored in the bedrock of standard renormalization-group invariance, the PMC simultaneously eradicates the factorial divergences and eliminates superfluous systematic errors, which inversely provides a good foundation for achieving high-precision pQCD predictions. Consequently, owing to its rigorous theoretical underpinnings, the PMC is eminently applicable to virtually all high-energy hadronic processes
Computing four-point functions with integrability, bootstrap and parity symmetry
No full textThe combination of integrability and crossing symmetry has proven to give tight non-perturbative bounds on some planar structure constants in =4 SYM, particularly in the setup of defect observables built on a Wilson-Maldacena line. Whereas the precision is good for the low lying states, higher in the spectrum it drops due to the degeneracies at weak coupling when considering a single correlator. As this could be a clear obstacle in restoring higher point functions, we studied the problem of bounding directly a 4-point function at generic cross ratio, showing how to adapt for this purpose the numerical bootstrap algorithms based on semidefinite programming. Another tool we are using to further narrow the bounds is a parity symmetry descending from the =4 SYM theory, which allowed us to reduce the number of parameters. We also give an interpretation for the parity in terms of the Quantum Spectral Curve at weak coupling. Our numerical bounds give an accurate determination of the 4-point function for physical values of the cross ratio, with at worst 5-6 digits precision at weak coupling and reaching more than 11 digits for 't Hooft coupling
Structural map of seas surrounding Italy
No full text<p>Structural map representing tectonic elements, earthquakes, rocky outcrops and volcanic seamounts identified in seas surrounding Italy, on top of a shaded relief bathymetry. It provides an overview of the tectonic setting of submerged areas and constitutes an update of the Structural model of Italy published in the 90s (Bigi et al., see references).</p>