Universit‘a di Salerno
We investigate the anisotropic stress parameter, η=Ψ/Φ\eta=\Psi/\Phi, defined as the ratio of the gravitational potentials in the linearly perturbed Friedmann-Lemaître Robertson-Walker metric, as a probe of deviations from general relativity across astrophysical to cosmological scales. Using mass profiles reconstructed from high-precision lensing and kinematics of nine galaxy clusters from the CLASH-VLT sample, we derive η(r)\eta(r) as a function of the radial distance from the cluster centres, over the range [0.1Mpc,1.2r200L][0.1 \,\text{Mpc},1.2\,r_{200}^L], where r200Lr_{200}^L is virial radius best-fit from lensing data. When using a Navarro-Frenk-White or an Hernquist profile to model the total matter distribution, we find consistency with general relativity (η=1\eta = 1) within 2σ2\sigma for the full radial range for all the sampled clusters. However, adopting a Burkert profile introduces mild tension with general relativity, reaching the 3σ3\sigma level in two systems. Assuming a negligible time-dependence in the redshift range spawned by the clusters, we obtain the joint constraint η(r=1.0Mpc)=0.930.40+0.48\eta (r= 1.0 \, \text{Mpc}) = 0.93^{+0.48}_{-0.40} (stat) ±0.47\pm 0.47 (syst) at 95%95\% confidence level -- an improvement of approximately 40%40\% over previous estimates. We discuss the impact of systematics on the constraints, and we highlight the implications of this result for current and upcoming cluster surveys.
As part of the Galactic Bulge Time Domain Survey (GBTDS), the Nancy Grace Roman Galactic Exoplanet Survey (RGES) will use microlensing to discover cold outer planets and free-floating planets unbound to stars. NASA has established several science requirements for the GBTDS to ensure RGES success. A key advantage of RGES is Roman's high angular resolution, which will allow detection of flux from many host stars. One requirement specifies that Roman must measure the masses and distances of 40% of detected planet hosts with 20% precision or better. To test this, we simulated microlensing events toward the GBTDS fields and used Fisher matrix analysis to estimate light curve parameter uncertainties. Combining these with Roman imaging observables (lens flux, relative lens-source proper motion), we estimated the achievable precision of lens mass and distance measurements. Using pyLIMASS, a publicly available code for estimating lens properties, we applied this analysis to 3,000 simulated events. Assuming the Cassan et al. (2012) exoplanet mass function, we find that >40% of host stars meet the required 20% precision threshold, confirming that the GBTDS can satisfy the mission requirement. We validated our approach by comparing our inferred lens masses and distances to empirical measurements from detailed image-constrained light curve modeling of historical microlensing events with Hubble and Keck follow-up imaging. Our results agree within roughly 1 sigma, demonstrating that both approaches yield consistent and reliable mass and distance estimates, and confirming the robustness of our simulations for Roman-era microlensing science.
This research theoretically establishes that electronic bands with spin-momentum locking intrinsically possess a finite quantum metric, a key concept in quantum geometry. It experimentally demonstrates this by observing a novel nonlinear in-plane magnetoresistance in 111-oriented LaAlO3/SrTiO3 interfaces, a system known for strong spin-orbit coupling, providing access to the real part of the quantum geometric tensor.
Researchers from the University of Salerno, University of Camerino, and Institut Ruder Bošković compared the Lindblad master equation with a first-principles microscopic model to describe entanglement and purity dynamics in open quantum systems. The study revealed fundamental discrepancies in short-time predictions when system openness stems from internal correlations, finding that the Lindblad approach could suppress entanglement and predicted linear purity decay, contrasting with the microscopic model's consistent entanglement generation and quadratic purity decay.
The surface states of 3D topological insulators possess geometric structures that imprint distinctive signatures on electronic transport. A prime example is the Berry curvature, which controls electric frequency doubling via a higher order moment, called Berry curvature triple. In addition to the Berry curvature, topological surface states are expected to exhibit a nontrivial quantum metric, which plays a key role in governing nonlinear magnetotransport. However, its manifestation has yet to be experimentally observed in 3D topological insulators. Here, we provide evidence for a nonlinear response activated by the quantum metric of the topological surface states of Sb2_2Te3_3. We measure a time-reversal odd, nonlinear magnetoresistance that is independent of temperature and disorder below 30 K and is thus of intrinsic geometrical origin. Our measurements demonstrate the existence of quantum geometry-induced transport in topological phases of matter and provide strategies for designing novel functionalities in topological devices.
The nonlinear Hall effect (NLHE) with time-reversal symmetry constitutes the appearance of a transverse voltage quadratic in the applied electric field. It is a second-order electronic transport phenomenon that induces frequency doubling and occurs in non-centrosymmetric crystals with large Berry curvature -- an emergent magnetic field encoding the geometric properties of electronic wavefunctions. The design of (opto)electronic devices based on the NLHE is however hindered by the fact that this nonlinear effect typically appears at low temperatures and in complex compounds characterized by Dirac or Weyl electrons. Here, we show a strong room temperature NLHE in the centrosymmetric elemental material bismuth synthesized in the form of technologically relevant polycrystalline thin films. The (1111\,1\,1) surface electrons of this material are equipped with a Berry curvature triple that activates side jumps and skew scatterings generating nonlinear transverse currents. We also report a boost of the zero field nonlinear transverse voltage in arc-shaped bismuth stripes due to an extrinsic geometric classical counterpart of the NLHE. This electrical frequency doubling in curved geometries is then extended to optical second harmonic generation in the terahertz (THz) spectral range. The strong nonlinear electrodynamical responses of the surface states are further demonstrated by a concomitant highly efficient THz third harmonic generation which we achieve in a broad range of frequencies in Bi and Bi-based heterostructures. Combined with the possibility of growth on CMOS-compatible and mechanically flexible substrates, these results highlight the potential of Bi thin films for THz (opto)electronic applications.
Recent experiments have reported nonlinear signals in topological materials up to room temperature. Here we show that this response stems from extrinsic spin-orbit contributions to \textit{both} impurity and phonon scattering. While skew scattering dominates at low temperatures, the side jump contribution τ/τβ\propto \tau/\tau_\beta, where τ\tau, τβ\tau_\beta are the momentum and skew scattering times respectively. Consequently side jump exhibits a weak temperature dependence and remains sizable at room temperature. Our results provide a roadmap for engineering nonlinear transport at ambient conditions.
Moduli spaces of semistable torsion-free sheaves on a K3 surface XX are often holomorphic symplectic varieties, deformation equivalent to a Hilbert scheme parametrizing zero-dimensional subschemes of XX. In fact this should hold whenever semistability is equivalent to stability. In this paper we study a typical "opposite" case, i.e. the moduli space McM_c of semistable rank-two torsion-free sheaves on XX with trivial determinant and second Chern class equal to an even number cc. The moduli space McM_c always contains points corresponding to strictly semistable sheaves. If cc is at least 4, then McM_c is singular along the locus parametrizing strictly semistable sheaves, and on the smooth locus of McM_c there is a symplectic holomorphic form. Thus it is natural to ask whether there is a symplectic desingularization of McM_c. We construct such a desingularization for c=4c=4; in another paper we show that this desingularization gives a new deformation class of (Kähler) holomorphic irreducible symplectic varieties (of dimension ten). We also study the case c>4c>4. We describe what should be an interesting desingularization, however we are not able to produce a symplectic one. In fact we suspect there is no symplectic smooth model of McM_c if c>4c>4 (and even, of course).
Internet of Things (IoT) devices often come with batteries of limited capacity that are not easily replaceable or rechargeable, and that constrain significantly the sensing, computing, and communication tasks that they can perform. The Simultaneous Wireless Information and Power Transfer (SWIPT) paradigm addresses this issue by delivering power wirelessly to energy-harvesting IoT devices with the same signal used for information transfer. For their peculiarity, these networks require specific energy-efficient planning and management approaches. However, to date, it is not clear what are the most effective strategies for managing a SWIPT network for energy efficiency. In this paper, we address this issue by developing an analytical model based on stochastic geometry, accounting for the statistics of user-perceived performance and base station scheduling. We formulate an optimization problem for deriving the energy optimal configuration as a function of the main system parameters, and we propose a genetic algorithm approach to solve it. Our results enable a first-order evaluation of the most effective strategies for energy-efficient provisioning of power and communications in a SWIPT network. We show that the service capacity brought about by users brings energy-efficient dynamic network provisioning strategies that radically differ from those of networks with no wireless power transfer.
Recently in \cite{FM, FlMo}, the language of MV-algebras was extended by adding a unary operation, an internal operator, called also a state-operator. In \cite{DD1}, a stronger version of state MV-algebras, called state-morphism MV-algebras was given. In this paper, we present Stone Duality Theorems for (i) the category of Boolean algebras with a fixed state-operator and the category of compact Hausdorff topological spaces with a fixed idempotent continuous function, and for (ii) the category of weakly divisible σ\sigma-complete state-morphism MV-algebras and the category of Bauer simplices whose set of extreme points is basically disconnected and with a fixed idempotent continuous function.
CNRS logoCNRSUniversity of Amsterdam logoUniversity of AmsterdamCharles UniversityNikhefJoint Institute for Nuclear ResearchCSICUniversity of GranadaTechnical University of Munich logoTechnical University of MunichAustralian National University logoAustralian National UniversityLeiden University logoLeiden UniversityCEA logoCEAUniversity of BelgradeUtrecht UniversityCadi Ayyad UniversityUniversity of JohannesburgMohammed V University in RabatAix-Marseille UnivCzech Technical University in PragueUniversit`a di BolognaIMT AtlantiqueUniversit`a di CataniaUniversitat Polit`ecnica de Val`enciaUniversite de NantesUniversitat de ValenciaNational Centre for Nuclear ResearchINFN-Sezione di GenovaINFN-Sezione di BolognaINFN Sezione di RomaUniversit`a Degli Studi Di Napoli “Federico II”Universite de StrasbourgUniversit‘a di SalernoUniversit\`a degli Studi della Campania "Luigi Vanvitelli"INFN Laboratori Nazionali del SudTbilisi State UniversityUniversity Mohammed IUniversity of JaenUniversit´e de MontpellierWitwatersrand UniversityIstituto Nazionale di Fisica Nucleare, Sezione di NapoliUniversite de ParisRoyal Netherlands Institute for Sea Research (NIOZ)Universite de Haute AlsaceINFN (Sezione di Bari)IFIC (Instituto de F´ısica Corpuscular)Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH)Universit´e Paris Cit´eUniversit´e Paris Cˆote d’AzurFriedrich-Alexander-Universit¨at Erlangen-N¨rnbergIstituto Nazionale di Fisica Nucleare - Sezione di CataniaUniversità di Ferrara* National and Kapodistrian University of Athens* North–West UniversityUniversita’ ”La Sapienza”Université Paris-SaclayUniversită di GenovaSorbonne Université
The measurement of the flux of muons produced in cosmic ray air showers is essential for the study of primary cosmic rays. Such measurements are important in extensive air shower detectors to assess the energy spectrum and the chemical composition of the cosmic ray flux, complementary to the information provided by fluorescence detectors. Detailed simulations of the cosmic ray air showers are carried out, using codes such as CORSIKA, to estimate the muon flux at sea level. These simulations are based on the choice of hadronic interaction models, for which improvements have been implemented in the post-LHC era. In this work, a deficit in simulations that use state-of-the-art QCD models with respect to the measurement deep underwater with the KM3NeT neutrino detectors is reported. The KM3NeT/ARCA and KM3NeT/ORCA neutrino telescopes are sensitive to TeV muons originating mostly from primary cosmic rays with energies around 10 TeV. The predictions of state-of-the-art QCD models show that the deficit with respect to the data is constant in zenith angle; no dependency on the water overburden is observed. The observed deficit at a depth of several kilometres is compatible with the deficit seen in the comparison of the simulations and measurements at sea level.
04 Feb 2010
We describe representation theorems for local and perfect MV-algebras in terms of ultraproducts involving the unit interval [0,1]. Furthermore, we give a representation of local Abelian lattice-ordered groups with strong unit as quasi-constant functions on an ultraproduct of the reals. All the above theorems are proved to have a uniform version, depending only on the cardinality of the algebra to be embedded, as well as a definable construction in ZFC. The paper contains both known and new results and provides a complete overview of representation theorems for such classes.
We discuss some fundamental issues underlying gravitational physics and point out some of the main shortcomings of Einstein's General Relativity. In particular, after taking into account the role of the two main objects of relativistic theories of gravity, i.e. the metric and the connection fields, we consider the possibility that they are not trivially related so that the geodesic structure and the causal structure of the spacetime could be disentangled, as supposed in the Palatini formulation of gravity. In this perspective, the Equivalence Principle, in its weak and strong formulations, can play a fundamental role in discriminating among competing theories. The possibility of its violation at quantum level could open new perspectives in gravitational physics and in unification with other interactions. We shortly debate the possibility of equivalence principle measurements by ground-based and space experiments.
Institute for Computational and Data SciencesCNRS logoCNRSAcademia SinicaUniversity of Cambridge logoUniversity of CambridgeMonash University logoMonash UniversityNational Central UniversityUniversita di PisaUniversity of Chicago logoUniversity of ChicagoNikhefGeorgia Institute of Technology logoGeorgia Institute of Technologythe University of Tokyo logothe University of TokyoPusan National UniversityStanford University logoStanford UniversityUniversity of Bristol logoUniversity of BristolUniversity of Copenhagen logoUniversity of CopenhagenThe Chinese University of Hong Kong logoThe Chinese University of Hong KongUniversity of MelbourneINFN logoINFNUniversity of WarsawUniversita di PerugiaNASA Goddard Space Flight Center logoNASA Goddard Space Flight CenterLouisiana State UniversityInternational Centre for Theoretical Sciences, Tata Institute of Fundamental ResearchUniversit‘a di Napoli Federico IIUniversity of Florida logoUniversity of FloridaUniversity of Minnesota logoUniversity of MinnesotaUniversity of Maryland logoUniversity of MarylandSeoul National University logoSeoul National UniversityNational Taiwan Normal UniversityThe Pennsylvania State University logoThe Pennsylvania State UniversityRochester Institute of TechnologyChennai Mathematical InstituteKing’s College London logoKing’s College LondonIndian Institute of Technology, BombayScuola Superiore MeridionaleNational Changhua University of EducationCharles Sturt UniversityAustralian National University logoAustralian National UniversityUniversity of Western AustraliaUniversity of GlasgowHigh Energy Accelerator Research Organization (KEK)The Graduate University for Advanced Studies (SOKENDAI)Universit`a degli Studi di GenovaWigner Research Centre for PhysicsUniversity of Alabama in HuntsvilleSyracuse UniversityNicolaus Copernicus Astronomical Center, Polish Academy of SciencesObservatoire de ParisInstituto Nacional de Pesquisas EspaciaisIndian Institute of Technology DelhiUniversitat de les Illes BalearsLomonosov Moscow State UniversitySouthwest Jiaotong UniversityUniversity of BirminghamNational Cheng Kung UniversityColl`ege de FranceNiels Bohr InstituteWashington State UniversityINFN, Laboratori Nazionali del Gran SassoGran Sasso Science Institute (GSSI)University of OregonCalifornia State University, FullertonNational Tsing-Hua UniversityBar Ilan UniversityUniversity of AdelaideUniversite Libre de BruxellesIndian Institute of Technology GandhinagarUniversit`a di BolognaMax Planck Institute for Gravitational Physics (Albert Einstein Institute)Universite catholique de LouvainUniversitat de ValenciaResonac CorporationInstitute for Plasma ResearchInter-University Centre for Astronomy and AstrophysicsWest Virginia UniversityCNR-SPINInstituto de Astrofísica de AndalucíaObservatoire de la Cˆote d’AzurIJCLabLaboratoire Kastler BrosselUniversity of ToyamaUniversit`a di Roma TreLaboratoire Charles CoulombUniversity of SzegedUniversity of Wisconsin–MilwaukeeNational Synchrotron Radiation Research CenterKorea Institute of Science and Technology InformationUniversite de StrasbourgLIGO Hanford ObservatoryUniversit‘a di SalernoLIGO, California Institute of TechnologyUniversit\'e C\^ote d'AzurLUTHThe University of Texas Rio Grande ValleyNational Astronomical Observatory of Japan (NAOJ)National Institute for Mathematical SciencesLIGO Livingston ObservatoryIP2I LyonLeibniz Universit\"at HannoverUniversit´e de MontpellierUniversit\`a degli Studi di Urbino ‘Carlo Bo’Laboratoire de l'Accelerateur LineaireUniversit`e de Li`egeLaboratoire de Physique des 2 Infinis Ir`ene Joliot-CurieInstitut FOTONUniversit`a degli Studi di UdineEuropean Gravitational Observatory (EGO)Inje UniversityUniversite du Littoral - Cote d’OpaleLaboratoire d’Annecy de Physique des Particules (LAPP)Universit`a della Campania “Luigi Vanvitelli”Universit´e Paris Cit´eIPHC UMR 7178Key Laboratory of Quantum Optics and Quantum InformationUniversit`a di Cassino e del Lazio MeridionaleUniversit`a degli Studi di SannioCentre Scientifique et Technique du BˆatimentDirectorate of Knowledge Management in Healthcare, Sree Chitra Tirunal Institute for Medical Sciences and TechnologyInstitute for Astronomical ScienceUniversit´e Claude Bernard (Lyon 1)Friedrich-Schiller-Universität JenaÉ́cole normale supérieureUniversita di ParmaUniversité Paris-SaclayUniversită di CagliariUniversità degli Studi di Napoli “Parthenope”Universita' di SienaUniv-RennesINAF Osservatorio Astronomico di PadovaUniversita di Roma ‘La Sapienza’Universita' di PadovaUniversité PSLSorbonne Université
We search for gravitational-wave signals associated with gamma-ray bursts detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (1 November 2019 15:00 UTC-27 March 2020 17:00 UTC).We conduct two independent searches: a generic gravitational-wave transients search to analyze 86 gamma-ray bursts and an analysis to target binary mergers with at least one neutron star as short gamma-ray burst progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these gamma-ray bursts. A weighted binomial test of the combined results finds no evidence for sub-threshold gravitational wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each gamma-ray burst. Finally, we constrain the population of low luminosity short gamma-ray bursts using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate.
Modern cosmological research still thoroughly debates the discrepancy between local probes and the Cosmic Microwave Background observations in the Hubble constant (\texorpdfstring{H0H_0}{H0}) measurements, ranging from 4 to 6σ\sigma. In the current study, we examine this tension using the Supernovae Ia (SNe Ia) data from the Pantheon, Pantheon+ (P+), Joint Lightcurve Analysis (JLA), and Dark Energy Survey, (DES) catalogs combined together into the so-called Master Sample. The sample contains 3714 SNe Ia, and is divided all of them into redshift-ordered bins. Three binning techniques are presented: the equi-population, the moving window (MW), and the equi-spacing in the \texorpdfstring{logz\log-z}{log-z}. We perform a Markov-Chain Monte Carlo analysis (MCMC) for each bin to determine the H0H_0 value, estimating it within the standard flat \texorpdfstring{Λ\LambdaCDM}{LCDM} and the \texorpdfstring{w0waw_{0}w_{a}CDM}{w0waCDM} models. These \texorpdfstring{H0H_0}{H0} values are then fitted with the following phenomenological function: \texorpdfstring{$\mathcal{H}_0(z) = \tilde{H}_0 / (1 + z)^\alpha$}{H0(z) = H0tilde / (1 + z)^alpha}, where \texorpdfstring{H~0\tilde{H}_0}{H0tilde} is a free parameter representing \texorpdfstring{H0(z)\mathcal{H}_0(z)}{H0(z)} fitted in \texorpdfstring{z=0z=0}{z=0}, and \texorpdfstring{α\alpha}{alpha} is the evolutionary parameter. Our results indicate a decreasing trend characterized by \texorpdfstring{α0.01\alpha \sim 0.01}{alpha ~ 0.01}, whose consistency with zero ranges from 1σ1 \sigma in 5 cases to 1 case at 3 σ\sigma and 11 cases at >3σ> 3 \sigma in several samples and configurations. Such a trend in the SNe Ia catalogs could be due to evolution with redshift for the astrophysical variables or unveiled selection biases. Alternatively, intrinsic physics, possibly the \texorpdfstring{f(R)f(R)}{f(R)} theory of gravity, could be responsible for this trend.
On demand current-driven insulator-to-metal transition (IMT) is pivotal for the next generation of energy-efficient and scalable microelectronics. IMT is a key phenomenon observed in various quantum materials, and it is enabled by the complex interplay of spin, lattice, charge, and orbital degrees of freedom (DOF). Despite significant prior work, the underlying mechanism of the current-driven IMT remains elusive, primarily due to the difficulty in simultaneously obtaining bulk fingerprints of all the electronic DOF. Here, we employ in-operando resonant inelastic x-ray scattering (RIXS) on Ca2_2RuO4_4, a prototypical strongly correlated material, to track the evolution of the electronic DOF encoded in the RIXS spectra during the current-driven IMT. Upon entering the conductive state, we observe an energy-selective suppression of the RIXS intensity, proportional to the current. Using complementary RIXS cross-section calculations, we demonstrate that the non-equilibrium conductive state emerges from the formation of correlated electronic states with a persistent Mott gap.
In recent years, central components of a new approach to linguistics, the Minimalist Program (MP) have come closer to physics. Features of the Minimalist Program, such as the unconstrained nature of recursive Merge, the operation of the Labeling Algorithm that only operates at the interface of Narrow Syntax with the Conceptual-Intentional and the Sensory-Motor interfaces, the difference between pronounced and un-pronounced copies of elements in a sentence and the build-up of the Fibonacci sequence in the syntactic derivation of sentence structures, are directly accessible to representation in terms of algebraic formalism. Although in our scheme linguistic structures are classical ones, we find that an interesting and productive isomorphism can be established between the MP structure, algebraic structures and many-body field theory opening new avenues of inquiry on the dynamics underlying some central aspects of linguistics.
The advanced interferometer network will herald a new era in observational astronomy. There is a very strong science case to go beyond the advanced detector network and build detectors that operate in a frequency range from 1 Hz-10 kHz, with sensitivity a factor ten better in amplitude. Such detectors will be able to probe a range of topics in nuclear physics, astronomy, cosmology and fundamental physics, providing insights into many unsolved problems in these areas.
08 Sep 2015
In this paper we review some of the main achievements of the semiring-theoretic approach to MV-algebras initiated and pursued mainly by the present authors and their collaborators. The survey focuses mainly on the connections between MV-algebras and other theories that such a semiringbased approach enabled, and on an application of such a framework to Digital Image Processing. We also give some suggestions for further developments by stating several open problems and possible research lines.
Systems with pronounced spin anisotropy play a pivotal role in advancing magnetization switching and spin-wave generation mechanisms, which are fundamental for spintronic technologies. Quasi-van der Waals ferromagnets, particularly Cr1+δ_{1+\delta}Te2_2 compounds, represent seminal materials in this field, renowned for their delicate balance between frustrated layered geometries and magnetism. Despite extensive investigation, the precise nature of their magnetic ground state, typically described as a canted ferromagnet, remains contested, as does the mechanism governing spin reorientation under external magnetic fields and varying temperatures. In this work, we leverage a multimodal approach, integrating complementary techniques, to reveal that Cr1+δ_{1+\delta}Te2_2 (δ=0.250.50\delta = 0.25 - 0.50) hosts a previously overlooked magnetic phase, which we term orthogonal-ferromagnetism. This single phase consists of alternating atomically sharp single layers of in-plane and out-of-plane ferromagnetic blocks, coupled via exchange interactions and as such, it differs significantly from crossed magnetism, which can be achieved exclusively by stacking multiple heterostructural elements together. Contrary to earlier reports suggesting a gradual spin reorientation in CrTe2_2-based systems, we present definitive evidence of abrupt spin-flop-like transitions. This discovery, likely due to the improved crystallinity and lower defect density in our samples, repositions Cr1+δ_{1+\delta}Te2_2 compounds as promising candidates for spintronic and orbitronic applications, opening new pathways for device engineering.
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