Results for "Giulia Semeghini"

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Collisions of self-bound quantum dropletsDec 21 2018We report on the study of binary collisions between quantum droplets formed by an attractive mixture of ultracold atoms. We distinguish two main outcomes of the collision, i.e. merging and separation, depending on the velocity of the colliding pair. The ... More
Parallel implementation of high-fidelity multi-qubit gates with neutral atomsAug 16 2019We report the implementation of universal two- and three-qubit entangling gates on neutral atom qubits encoded in long-lived hyperfine ground states. The gates are mediated by excitation to strongly interacting Rydberg states, and are implemented in parallel ... More
Universality of the three-body Efimov parameter at narrow Feshbach resonancesMar 15 2013We measure the critical scattering length for the appearance of the first three-body bound state, or Efimov three-body parameter, at seven different Feshbach resonances in ultracold 39K atoms. We study both intermediate and narrow resonances, where the ... More
Measurement of the mobility edge for 3D Anderson localizationApr 14 2014Anderson localization is a universal phenomenon affecting non-interacting quantum particles in disorder. In three spatial dimensions it becomes particularly interesting to study because of the presence of a quantum phase transition from localized to extended ... More
Non parametric Bayesian approach to LR assessment in case of rare haplotype matchJun 28 2015Sep 18 2015The evaluation of a match between the DNA profile of a stain found on a crime scene and that of a suspect (previously identified) involves the use of the unknown parameter $p=(p_1, p_2, ...)$, (the ordered vector which represents the proportions of the ... More
QCD and Collider ProcessesJan 18 2012Jan 24 2012I review the status of today's theoretical description of Standard Model processes relevant for Tevatron and LHC analyses, and of the tools that are used in phenomenological studies. I will also discuss a few recent ideas to further refine our abilities ... More
Studies of Open Charm and Charmonium Production at LHCbAug 23 2010We present recent results from charmonium and open charm production at the LHCb experiment at CERN, Geneva. We concentrate on studies for the measurement of the cross section pp ->JPsi+X in its decay channel with two muons, showing the agreement of the ... More
Sublinear Growth of Information in DNA SequencesFeb 27 2004We introduce a novel method to analyse complete genomes and recognise some distinctive features by means of an adaptive compression algorithm, which is not DNA-oriented. We study the Information Content as a function of the number of symbols encoded by ... More
Seminumerical resummation of event shapes and jet ratesMay 13 2002May 15 2002For many observables, the most difficult part of a single logarithmic resummation is the analytical treatment of the observable's dependence on multiple emissions. We present a general numerical method, which allows the resummation specifically of these ... More
Impact of model choice on LR assessment in case of rare haplotype match (frequentist approach)Feb 13 2015Apr 13 2016The likelihood ratio (LR) measures the relative weight of forensic data regarding two hypotheses. Several levels of uncertainty arise if frequentist methods are chosen for its assessment: the assumed population model only approximates the true one and ... More
Relative compactified Jacobians of linear systems on Enriques surfacesOct 28 2012Jan 18 2016We study certain moduli spaces of sheaves on Enriques surfaces thereby obtaining, in every odd dimension, new examples of Calabi--Yau manifolds. We describe the geometry (canonical bundle, fundamental group, second Betti number and certain Hodge numbers) ... More
ANTARES and IceCube combined search for neutrino point-like and extended sources in the Southern SkyAug 20 2019The ANTARES neutrino telescope, located in the Mediterranean Sea, and the IceCube neutrino observatory, located at the geographic South Pole, both search for cosmic neutrino events with an instantaneous full-sky field of view. The different characteristics ... More
A microsimulation of traders activity in the stock market: the role of heterogeneity, agents' interactions and trade frictionsMay 13 1999Jul 25 2000We propose a model with heterogeneous interacting traders which can explain some of the stylized facts of stock market returns. In the model synchronization effects, which generate large fluctuations in returns, can arise either from an aggregate exogenous ... More
Scaling and Multi-scaling in Financial MarketsJul 25 2000This paper reviews some of the phenomenological models which have been introduced to incorporate the scaling properties of financial data. It also illustrates a microscopic model, based on heterogeneous interacting agents, which provides a possible explanation ... More
Supersymmetry results at the TevatronMay 17 2005The Run II physics programme of the Tevatron is proceeding with more than 300 pb-1 of analysis quality data, collected at a centre-of-mass energy of 1.96 TeV. Searches for supersymmetric particles are starting to set new limits, improving over the LEP ... More
Semileptonic B and D decays-latest developmentsSep 25 2012Oct 17 2012Semileptonic B and D decays are on a well deserved podium to extract CKM matrix elements, to validate theoretical tools and, more recently, even to look for hints of new physics. Here we review the latest updates.
Radiative and semileptonic B meson decay spectraAug 19 2006We review semi-inclusive charmless B decays, focussing on threshold logarithmic resumming and on universality of QCD dynamics in radiative and semileptonic decays.
Automated resummation of final state observables in QCDMay 15 2003We present an innovative method to resum infrared and collinear logarithms appearing in distributions of jet observables in QCD. The method, based on a general master formula with applicability conditions, allows resummations at next-to-leading logarithmic ... More
Gieseker conjecture for homogeneous spacesDec 07 2016We prove Gieseker conjecture for an homogeneous space $X$, saying that if $X$ has no non-trivial tame coverings then it has no non-trivial regular singular $\mathscr{O}_X$-coherent $\mathscr{D}_{X/k}$-modules. In order to do so we prove a K\"unneth formula ... More
Bayesian approach to LR assessment in case of rare type match: careful derivation and limitsFeb 09 2015Apr 13 2016The likelihood ratio (LR) is largely used to evaluate the relative weight of forensic data regarding two hypotheses and for its assessment Bayesian methods are widespread in the forensic field. However, the Bayesian `recipe' for the LR presented in most ... More
QCD and High Energy Interactions: Moriond 2015 Theory SummaryJul 07 2015I will summarise the new theory developments that emerged during the 2015 QCD Moriond conference. I will give my perspective on some of the topics and emphasise what I consider most relevant.
Quantum states as virtual singletons: converting duality into symmetryApr 09 2013In a predicative framework from basic logic, defined for a model of quantum parallelism by sequents, we characterize a class of first order domains, termed {\em virtual singletons}, which allows a generalization of the notion of duality, termed {\em symmetry}. ... More
Semileptonic B decaysJan 18 2013We review recent progress in exclusive B --> D^(*) and inclusive B --> X(u) semileptonic B decays
Semileptonic D decays and eta-eta^prime mixingSep 15 2012Dec 27 2012We discuss the impact of recent progress in semileptonic D decays on light flavour spectroscopy and estimate mixing parameters in the eta-eta^prime system.
Quaternionic Hankel operators and approximation by slice regular functionsJan 09 2015Nov 15 2016In this paper we study Hankel operators in the quaternionic setting. In particular we prove that they can be exploited to measure the $L^{\infty}$ distance of a slice $L^{\infty}$ function from the space of bounded slice regular functions.
The variation of the monodromy group in families of stratified bundles in positive characteristicMay 20 2014Jan 05 2015In this article we study smooth families of stratified bundles in positive characteristic and the variation of their monodromy group.Our aim is, in particular, to strengthen the weak form of the positive equicharacteristic $p$-curvature conjecture stated ... More
Semileptonic and leptonic $B$ decays, circa 2016Oct 14 2016We summarize the status of semileptonic and leptonic $B$ decays, including $|V_{cb}|$ and $|V_{ub}|$ exclusive and inclusive determinations, decays to excited states of the charm meson spectrum and decays into $\tau$ leptons.
Determination of the CKM matrix elements |V(xb)|May 13 2013Jul 08 2013We review the current status of |V(cb)|, |V(ub)| and |V(tb)|, the absolute values of the matrix elements in the CKM third column.
Magnitudes of V(xb) CKM matrix elementsJun 05 2013Jul 08 2013We review the current status of the absolute values of the CKM matrix elements V(xb), with particular attention to latest determinations.
Threshold resummed spectra in semi-inclusive B decaysJul 05 2006I discuss some aspects of the universality of soft gluon dynamics in semileptonic and radiative decays at the threshold region.
Electroweak Physics Results at CDF Run IIMay 19 2004The Run II physics program of CDF is proceeding with approximately 200 pb-1 of analysis quality data collected at the center-of-mass energy of 1.96 TeV. The Electroweak measurements are among the first and most important benchmarks towards the best understanding ... More
Accurate predictions for heavy quark jetsMay 14 2007Heavy-flavour jets enter many of today's collider studies, yet NLO predictions for these quantities are subject to large uncertainties, larger than the corresponding experimental errors. We propose a new, infrared safe definition of heavy-quark jets which ... More
Resummed event shapes at hadron collidersOct 04 2004We present recently defined jet-observables for hadron-hadron dijet production, which are designed to reconcile the seemingly conflicting theoretical requirement of globalness, which makes it possible to resum them (automatically) at NLL accuracy and ... More
Basic Logic and Quantum Computing: Logical Judgements by an Insider ObserverJul 07 2004We consider the logical assertions of a hypothetical observer who is inside a quantum computer and performs a reversible quantum measurement, obtaining a symmetric couple of new axioms, valid only inside the quantum computer. The result is that, in this ... More
Automated resummation of jet observables in QCDAug 29 2003We present a master formula, with applicability conditions, which allows us to automate the resummation of infrared and collinear logarithms appearing in distributions of jet observables in QCD at next-to-leading logarithmic accuracy.
Theoretical Review of Radiative Rare B DecaysOct 30 1995A status report on the theory of radiative rare $B$ decays in the standard model is presented, with focus on inclusive decays $B \rightarrow X_{(s,d)}\, \gamma$ and exclusive decays $B \rightarrow (K^\ast,\omega,\rho) \, \gamma$. CP asymmetries are also ... More
Short and Long Distance Interplay in Inclusive $ B \to X_d γ$ DecaysFeb 13 1995Jun 29 1995We analyze the short and long distance contributions to inclusive $B \rightarrow X_d \gamma$ decay, paying particular attention to the dependence on the Cabibbo-Kobayashi-Maskawa parameter $V_{td}$. We discuss penguin diagrams with internal $u$ and $c$ ... More
Quaternionic Hankel operators and approximation by slice regular functionsJan 09 2015In this paper we study Hankel operators in the quaternionic setting. In particular we prove that they can be exploited to measure the $L^{\infty}$ distance of a slice $L^{\infty}$ function from the space of bounded slice regular functions.
A theory of Galois descent for finite inseparable extensionsSep 17 2015Oct 22 2015We present a generalization of Galois descent to finite modular normal field extension $L/K$, using the Heerma-Galois group $Aut(L[\bar{X}]/K[\bar{X}])$ where $L[\bar{X}]=L[X]/(X^{p^e})$ and $e$ is the exponent of $L$ over $K$.
The base change of the monodromy group for geometric Tannakian pairsJan 25 2016We prove that in any characteristic the formation of the monodromy group of a $\mathscr{D}$-module commutes with the extension of the ground field, extending a result of Gabber for separable extensions.
Status of $|V_{cb}|$ and $|V_{ub}|$ CKM matrix elementsDec 13 2014We summarize the status of $|V_{cb}|$ and $|V_{ub}|$ determinations, including the long standing tension among exclusive and inclusive determinations. We also discuss $B$ meson semileptonic decays to excited states of the charm meson spectrum and leptonic ... More
Brief review on semileptonic B decaysSep 06 2012Oct 05 2012We concisely review semileptonic B decays, focussing on recent progress on both theoretical and experimental sides.
Characterization of quantum states in predicative logicFeb 08 2011Jul 15 2011We develop a characterization of quantum states by means of first order variables and random variables, within a predicative logic with equality, in the framework of basic logic and its definitory equations. We introduce the notion of random first order ... More
CP violation with BsMay 12 2012The observation of CP violation effects is becoming more and more significant in a variety of channels, due to the impressive experimental effort of the last years. We review recent progress in Bs semileptonic decays and in Bs decays into CP eigenstates. ... More
Effective theory approach to unstable particlesMay 13 2004May 27 2004We present a novel treatment of resonant massive particles appearing as intermediate states in high energy collisions. The approach uses effective field theory methods to treat consistently the instability of the intermediate resonant state. As a result ... More
A dynamical approach to semi-inclusive B decaysNov 30 2006Dec 22 2006A dynamical approach to semi-inclusive decays based on an effective running coupling for the strong interactions is described.
Progress on semi-leptonic $B_{(s)}$ decaysMar 30 2014May 25 2014We report on the current status of semi-leptonic $B_{(s)}$ decays, including rare decays, and the extraction of the absolute values of the CKM matrix elements $|V_{cb}|$ and $|V_{ub}|$.
The Casas-Alvero conjectureNov 16 2015Nov 19 2015We present a proof of the Casas-Alvero conjecture, stating that if a complex polynomial has a root in common with each of its derivatives it must be a multiple of the power of some monomial.
A classification of certain almost $α$-Kenmotsu manifoldsJun 24 2010We study $\mathcal D$-homothetic deformations of almost $\alpha$-Kenmotsu structures. We characterize almost contact metric manifolds which are $CR$-integrable almost $\alpha$-Kenmotsu manifolds, through the existence of a canonical linear connection, ... More
The normal hull and commutator group for nonconnected group schemesMar 19 2018In this short note, we prove that there is a well behaved notion of normal hull for smooth algebraic group schemes over a field and that the commutator group $(G,H)$ is well defined for $H\subset G$ smooth, even when both of them are not connected.
Relative compactified Jacobians of linear systems on Enriques surfacesOct 28 2012May 08 2019We study certain moduli spaces of sheaves on Enriques surfaces thereby obtaining, in every odd dimension, new examples of Calabi-Yau manifolds. We describe the geometry (canonical bundle, fundamental group, second Betti number and certain Hodge numbers) ... More
Parallel implementation of high-fidelity multi-qubit gates with neutral atomsAug 16 2019Aug 20 2019We report the implementation of universal two- and three-qubit entangling gates on neutral atom qubits encoded in long-lived hyperfine ground states. The gates are mediated by excitation to strongly interacting Rydberg states, and are implemented in parallel ... More
From Hankel operators to Carleson measures in a quaternionic variableJul 31 2014We introduce and study Hankel operators defined on the Hardy space of regular functions of a quaternionic variable. Theorems analogous to those of Nehari anc C. Fefferman are proved.
Patterns of consumption in a discrete choice model with asymmetric interactionsOct 30 2000Oct 31 2000We study the consumption behaviour of an asymmetric network of heterogeneous agents in the framework of discrete choice models with stochastic decision rules. We assume that the interactions among agents are uniquely specified by their ``social distance'' ... More
Criticality in a model of banking crisesApr 04 2001An interbank market lets participants pool the risk arising from the combination of illiquid investments and random withdrawals by depositors. But it also creates the potential for one bank's failure to trigger off avalanches of further failures. We simulate ... More
Universal Lie Formulas for Higher AntibracketsSep 30 2015Jun 06 2016We prove that the hierarchy of higher antibrackets (aka higher Koszul brackets, aka Koszul braces) of a linear operator $\Delta$ on a commutative superalgebra can be defined by some universal formulas involving iterated Nijenhuis-Richardson brackets having ... More
W+W-, WZ and ZZ production in the POWHEG BOX V2Nov 06 2013Nov 11 2013We present an implementation of the vector boson pair production processes ZZ, W+W- and WZ within the POWHEG BOX V2. This implementation, derived from the POWHEG BOX version, has several improvements over the old one, among which the inclusion of all ... More
Parabolic inverse convection-diffusion-reaction problem solved using an adaptive parametrizationOct 11 2011This paper investigates the solution of a parabolic inverse problem based upon the convection-diffusion-reaction equation, which can be used to estimate both water and air pollution. We will consider both known and unknown source location: while in the ... More
W+3 jet production at the LHC as a signal or backgroundOct 19 2009We discuss the production of W bosons in association with three jets at the LHC. We investigate how next-to-leading order QCD corrections modify basic kinematic distributions of jets and leptons. We also address the magnitude of NLO QCD effects in W+3 ... More
Standard model for liquid water withstands x-ray probeDec 17 2005We present a series of ab-initio calculations of spectroscopic properties of liquid water at ambient conditions. Our results show that all available theoretical and experimental evidence is consistent with the standard model of the liquid as comprising ... More
The internal logic of Bell's statesDec 26 2004We investigate the internal logic of a quantum computer with two qubits, in the two particular cases of non-entanglement (separable states) and maximal entanglement (Bell's states). To this aim, we consider an internal (reversible) measurement which preserves ... More
Interplay between perturbative and non-perturbative QCD in three-jet eventsJan 16 2001We present the perturbative (PT) and non-perturbative (NP) analysis of the cumulative out-of-event-plane momentum distribution in e+e- annihilation in the near-to-planar three-jet region. A physical interpretation based on simple QCD considerations and ... More
Real-Space Adaptive-Coordinate Electronic Structure CalculationsJun 20 1995We present a real-space adaptive-coordinate method, which combines the advantages of the finite-difference approach with the accuracy and flexibility of the adaptive coordinate method. The discretized Kohn-Sham equations are written in generalized curvilinear ... More
Large scale GW calculationsJan 13 2015We present GW calculations of molecules, ordered and disordered solids and interfaces, which employ an efficient contour deformation technique for frequency integration, and do not require the explicit evaluation of virtual electronic states, nor the ... More
From Hankel operators to Carleson measures in a quaternionic variableJul 31 2014Nov 22 2016We introduce and study Hankel operators defined on the Hardy space of regular functions of a quaternionic variable. Theorems analogous to those of Nehari anc C. Fefferman are proved.
Long distance effects in semi-inclusive B decaysSep 28 2006We discuss some issues on factorization of long distance effects for semi-inclusive B decay spectra in full QCD and in the effective theory.
Approximate NNLO Threshold Resummation in Heavy Flavour DecaysApr 11 2002Aug 01 2002We present an approximate NNLO evaluation of the QCD form factor resumming large logarithmic perturbative contributions in semi-inclusive heavy flavour decays.
Primordial standing wavesNov 15 2017We consider the possibility that the primordial fluctuations (scalar and tensor) might have been standing waves at their moment of creation, whether or not they had a quantum origin. We lay down the general conditions for spatial translational invariance, ... More
Properties of the American price function in the Heston-type modelsApr 02 2019We study some properties of the American option price in the stochastic volatility Heston model. We first prove that, if the payoff function is convex and satisfies some regularity assumptions, then the option value function is increasing with respect ... More
Variational formulation of American option prices in the Heston ModelNov 30 2017Dec 11 2018We give an analytical characterization of the price function of an American option in Heston-type models. Our approach is based on variational inequalities and extends recent results of Daskalopoulos and Feehan (2011). We study the existence and uniqueness ... More
Luce, Trasparenze e Cinema tra Arte e Scienza - Light, Transparency and Cinema between Art and ScienceJan 22 2009From light and physical phenomena to cinema, an interdisciplinary percourse between art and science, from historical and critical references to the ultimate digital frontiers, including digital movies revolution, stereoscopy, holography, interfaces. ----- ... More
The hunt for red AGN: a new infrared diagnosticJul 11 2014We introduce a new infrared diagnostic to separate galaxies on the basis of their dominant infrared emission: stellar or nuclear. The main novelty with respect to existing diagnostics, is the usage of a broad band encompassing at the same time the 9.7micron ... More
A Comparison of High-Frequency Cross-Correlation MeasuresFeb 19 2004On a high-frequency scale the time series are not homogeneous, therefore standard correlation measures can not be directly applied to the raw data. There are two ways to deal with this problem. The time series can be homogenised through an interpolation ... More
Life of cosmological perturbations in MDR models, and the prospect of travelling primordial gravitational wavesMay 21 2019We follow the life of a generic primordial perturbation mode (scalar or tensor) subject to modified dispersion relations (MDR), as its proper wavelength is stretched by expansion. A necessary condition ensuring that travelling waves can be converted into ... More
Scalar multiplication in compressed coordinates in the trace-zero subgroupSep 13 2017We consider trace-zero subgroups of elliptic curves over a degree three field extension. The elements of these groups can be represented in compressed coordinates, i.e. via the two coefficients of the line that passes through the point and its two Frobenius ... More
Surface tension controls the onset of gyrification in brain organoidsMay 09 2019Understanding the mechanics of brain embryogenesis can provide insights on pathologies related to brain development, such as lissencephaly, a genetic disease which cause a reduction of the number of cerebral sulci. Recent experiments on brain organoids ... More
Attainability property for a probabilistic target in Wasserstein spacesApr 24 2019In this paper we establish an attainability result for the minimum time function of a control problem in the space of probability measures endowed with Wasserstein distance. The dynamics is provided by a suitable controlled continuity equation, where ... More
The fate of carbon dioxide in water-rich fluids at extreme conditionsAug 28 2016Investigating the fate of dissolved carbon dioxide under extreme conditions is critical to understanding the deep carbon cycle in the Earth, a process that ultimately influences global climate change. We used first-principles molecular dynamics simulations ... More
Kinematics of particles with quantum de Sitter symmetriesDec 10 2015We present the first detailed study of the kinematics of free relativistic particles whose symmetries are described by a quantum deformation of the de Sitter algebra, known as $q$-de Sitter Hopf algebra. The quantum deformation parameter is a function ... More
Hyperelliptic Integrals and Mirrors of the Johnson-Kollár del Pezzo SurfacesJan 25 2019Jul 23 2019For all k>0 integer, we consider the regularised I-function of the family of del Pezzo surfaces of degree 8k+4 in P(2,2k+1,2k+1, 4k+1), first constructed by Johnson and Koll\'ar. We show that this function, which is of hypergeometric type, is a period ... More
Patterns of consumption in socio-economic models with heterogeneous interacting agentsSep 09 1999We study consumption behaviour in systems with heterogeneous interacting agents. Two different models are introduced, respectively with long and short range interactions among agents. At any time step an agent decides whether or not to consume a good, ... More
On the quantum mechanical three-body problem with zero-range interactionsJan 29 2016In this note we discuss the quantum mechanical three-body problem with pairwise zero-range interactions in dimension three. We review the state of the art concerning the construction of the corresponding Hamiltonian as a self-adjoint operator in the bosonic ... More
The diffuse supernova neutrino background: Expectations and uncertainties derived from SN1987AFeb 02 2011Context: The detection of the diffuse supernova neutrino background may be imminent, but theoretical predictions are affected by substantial uncertainties. AIMS. We calculate the signal and its uncertainty with the present configuration of Super-Kamiokande ... More
A model for next-to-leading order threshold resummed form factorsJul 20 2004Nov 23 2004We present a model for next-to-leading order resummed threshold form factors based on a time-like coupling recently introduced in the framework of small x physics. Improved expressions for the form factors in N-space are obtained which are not plagued ... More
The structure function of semi-inclusive heavy flavour decays in field theoryMar 15 2000Sep 20 2000We consider the decay of a heavy flavour into an inclusive hadronic state X of invariant mass m_X small with respect to its energy E_X, m_X << E_X. The electron spectrum and the hadronic mass distribution in semileptonic b -> u decays, or the photon spectrum ... More
On the maximum drawdown during speculative bubblesJul 27 2006Nov 03 2006A taxonomy of large financial crashes proposed in the literature locates the burst of speculative bubbles due to endogenous causes in the framework of extreme stock market crashes, defined as falls of market prices that are outlier with respect to the ... More
Relativistic compatibility of the interacting $κ$-Poincaré model and implications for the relative locality frameworkMar 11 2019We investigate the relativistic properties under boost transformations of the $\kappa$-Poincar\'e model with multiple causally connected interactions, both at the level of its formulation in momentum space only and when it is endowed with a full phase ... More
Birth of colliding beams in Europe, two photon studies at AdoneNov 02 2015This article recalls the birth of the first electron-positron storage ring AdA, and the construction of the higher energy collider ADONE, where early photon-photon collisions were observed. The events which led the Austrian physicist Bruno Touschek to ... More
Complex-valued information entropy measure for networks with directed links (digraphs). Application to citations by community agents with opposite opinionsFeb 03 2013The notion of complex-valued information entropy measure is presented. It applies in particular to directed networks (digraphs). The corresponding statistical physics notions are outlined. The studied network, serving as a case study, in view of illustrating ... More
Dynamical phase transition in the 1D-transverse field Ising chain characterized by the transverse magnetization spectral functionMar 08 2019We study a 1D-Quantum Ising Model in transverse field driven out of equilibrium by performing a composite quantum quench to deduce the asymptotic properties of the transverse magnetization stationary state via the analysis of the spectral function. What ... More
Contraction and regularizing properties of heat flows in metric measure spacesApr 22 2019We illustrate some novel contraction and regularizing properties of the Heat flow in metric-measure spaces that emphasize an interplay between Hellinger-Kakutani, Kantorovich-Wasserstein and Hellinger-Kantorvich distances. Contraction properties of Hellinger-Kakutani ... More
Representations of Affine Group Schemes Over General RingsJul 03 2018Aug 07 2018Among all affine, flat, finitely presented group schemes, we focus on those that are pure, this includes all groups which are extensions of a finite locally free group by a group with connected fibres. We prove that over an arbitrary base ring, pure group ... More
Invariant metrics for the quaternionic Hardy spaceDec 20 2013Dec 23 2013Riemannian metrics on the unit ball of the quaternions, which are naturally associated with the reproducing kernel Hilbert spaces. We study the metric arising from the Hardy space in detail. We show that, in contrast to the one-complex variable case, ... More
Singularities of moduli spaces of sheaves on K3 surfaces and Nakajima quiver varietiesMay 04 2015Mar 10 2018The aim of this paper is to study the singularities of certain moduli spaces of sheaves on K3 surfaces by means of Nakajima quiver varieties. The singularities in question arise from the choice of a non--generic polarization, with respect to which we ... More
A continuum model of skeletal muscle tissue with loss of activationJan 26 2017We present a continuum model for the mechanical behavior of the skeletal muscle tissue when its functionality is reduced due to aging. The loss of ability of activating is typical of the geriatric syndrome called sarcopenia. The material is described ... More
Generalizations of 3-Sasakian manifolds and skew torsionApr 18 2018In the first part, we define and investigate new classes of almost 3-contact metric manifolds, with two guiding ideas in mind: first, what geometric objects are best suited for capturing the key properties of almost 3-contact metric manifolds, and second, ... More
On the modeling of internal parameters in hyperelastic biological materialsSep 28 2016This paper concerns the behavior of hyperelastic energies depending on an internal parameter. First, the situation in which the internal parameter is a function of the gradient of the deformation is presented. Second, two models where the parameter describes ... More
Constraints on cosmological birefringence energy dependence from CMB polarization dataNov 14 2012Feb 15 2013We study the possibility of constraining the energy dependence of cosmological birefringence by using CMB polarization data. We consider four possible behaviors, characteristic of different theoretical scenarios: energy-independent birefringence motivated ... More
Relative Locality in $κ$-PoincaréJun 28 2011Jul 03 2013We show that the $\kappa$-Poincar\'e Hopf algebra can be interpreted in the framework of curved momentum space leading to the relativity of locality \cite{AFKS}. We study the geometric properties of the momentum space described by $\kappa$-Poincar\'e, ... More
Two photon width of eta_cOct 16 2001We discuss the measured partial width of the pseudoscalar charmonium state, $\eta_c$, into two photons. Predictions from potential models are examined and compared with experimental values. Including radiative corrections, it is found that present measurements ... More