Results for "Enrico Rinaldi"

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Exact sampling of corrugated surfacesOct 15 2008We discuss an algorithm for the exact sampling of vectors v in [0,1]^N satisfying a set of pairwise difference inequalities. Applications include the exact sampling of skew Young Tableaux, of configurations in the Bead Model, and of corrugated surfaces ... More
Gauged And Ungauged: A Nonperturbative TestFeb 08 2018We study the thermodynamics of the `ungauged' D0-brane matrix model by Monte Carlo simulation. Our results appear to be consistent with the conjecture by Maldacena and Milekhin.
Lattice QCD determination of neutron-antineutron matrix elements with physical quark massesJan 22 2019Matrix elements of six-quark operators are needed to extract new physics constraints from experimental searches for neutron-antineutron oscillations. This work presents in detail the first lattice quantum chromodynamics calculations of the necessary neutron-antineutron ... More
Neutron-antineutron oscillations from lattice QCDSep 01 2018Jan 24 2019Fundamental symmetry tests of baryon number violation in low-energy experiments can probe beyond the Standard Model (BSM) explanations of the matter-antimatter asymmetry of the universe. Neutron-antineutron oscillations are predicted to be a signature ... More
Extra-dimensional models on the latticeMay 13 2016Aug 09 2016In this review we summarize the ongoing effort to study extra-dimensional gauge theories with lattice simulations. In these models the Higgs field is identified with extra-dimensional components of the gauge field. The Higgs potential is generated by ... More
Scalar mass corrections from compact extra dimensions on the latticeMar 26 2012We explore the phase diagram of the SU(2) Yang-Mills theory in 5 dimensions by numerical simulations. The lattice system shows a dimensionally-reduced phase where the extra dimension is small compared to the four dimensional correlation length. In the ... More
Investigation of the scalar spectrum in SU(3) with eight degenerate flavorsOct 22 2015The Lattice Strong Dynamics collaboration is investigating the properties of a SU(3) gauge theory with $N_f = 8$ light fermions on the lattice. We measure the masses of the lightest pseudoscalar, scalar and vector states using simulations with the nHYP ... More
Light scalar spectrum in extra-dimensional gauge theoriesNov 05 2012The phase diagram of five-dimensional SU(2) gauge theories with one compactified dimension on anisotropic lattices has a rich structure. In this contribution we show how to control non-perturbatively the scale hierarchy between the cut-off and the compactification ... More
Vulnerability and power on networksDec 19 2013Dec 19 2014Inspired by socio-political scenarios, like dictatorships, in which a minority of people exercise control over a majority of weakly interconnected individuals, we propose vulnerability and power measures defined on groups of actors of networks. We establish ... More
Light scalars in strongly-coupled extra-dimensional theoriesMar 09 2012Jul 03 2012The low-energy dynamics of five-dimensional Yang-Mills theories compactified on S^1 can be described by a four-dimensional gauge theory coupled to a scalar field in the adjoint representation of the gauge group. Perturbative calculations suggest that ... More
The vanishing of strong turbulent fronts in bent pipesFeb 06 2019Isolated patches of turbulence in transitional straight pipes are sustained by a strong instability at their upstream front, where the production of turbulent kinetic energy (TKE) is up to five times higher than in the core. Direct numerical simulations ... More
Lattice QCD input for axion cosmologyMay 27 2015One intriguing BSM particle is the QCD axion, which could simultaneously provide a solution to the Strong CP problem and account for some, if not all, of the dark matter density in the universe. This particle is a pNGB of the conjectured Peccei-Quinn ... More
Glueball masses in the large N limitJul 22 2010Jun 15 2011The lowest-lying glueball masses are computed in SU($N$) gauge theory on a spacetime lattice for constant value of the lattice spacing $a$ and for $N$ ranging from 3 to 8. The lattice spacing is fixed using the deconfinement temperature at temporal extension ... More
SU(N_c) gauge theories at deconfinementFeb 29 2012May 10 2012The deconfinement transition in SU($N_c$) Yang--Mills is investigated by Monte Carlo simulations of the gauge theory discretized on a spacetime lattice. We present new results for $ 4 \le N_c \le 8$ (in particular, for $N_c = 5$ and $N_c = 7$), which ... More
The glueball spectrum at large NOct 28 2010The lowest-lying glueball masses are computed in SU($N$) gauge theory on a spacetime lattice for constant value of the lattice spacing $a$ and for $N$ ranging from 3 to 8. The lattice spacing is fixed using the deconfinement temperature at temporal extension ... More
Slow motion for the nonlocal Allen-Cahn equation in n-dimensionsDec 05 2015The goal of this paper is to study the slow motion of solutions of the nonlocal Allen-Cahn equation in a bounded domain $\Omega \subset \mathbb{R}^n$, for $n > 1$. The initial data is assumed to be close to a configuration whose interface separating the ... More
Indecomposable $1$-factorizations of the complete multigraph $λ K_{2n}$ for every $λ\leq 2n$Nov 10 2016A $1$-factorization of the complete multigraph $\lambda K_{2n}$ is said to be indecomposable if it cannot be represented as the union of $1$-factorizations of $\lambda_0 K_{2n}$ and $(\lambda-\lambda_0) K_{2n}$, where $\lambda_0<\lambda$. It is said to ... More
The transition to a layered phase in the anisotropic five-dimensional SU(2) Yang-Mills theoryMay 03 2013We extend to large lattices the work of a previous investigation of the phase diagram of the anisotropic five-dimensional SU(2) Yang-Mills model using Monte Carlo simulations in the regime where the lattice spacing in the fifth dimension is larger than ... More
Nonperturbative investigations of SU(3) gauge theory with eight dynamical flavorsJul 23 2018Jan 16 2019We present our lattice studies of SU(3) gauge theory with $N_f$ = 8 degenerate fermions in the fundamental representation. Using nHYP-smeared staggered fermions we study finite-temperature transitions on lattice volumes as large as $L^3 \times N_t = 48^3 ... More
Infrared conformality and bulk critical points: SU(2) with heavy adjoint quarksSep 06 2013The lattice phase structure of a gauge theory can be a serious obstruction to Monte Carlo studies of its continuum behaviour. This issue is particularly delicate when numerical studies are performed to determine whether a theory is in a (near-)conformal ... More
Scaling properties of SU(2) gauge theory with mixed fundamental-adjoint actionDec 04 2012We study the phase diagram of the SU(2) lattice gauge theory with fundamental-adjoint Wilson plaquette action. We confirm the presence of a first order bulk phase transition and we estimate the location of its end-point in the bare parameter space. If ... More
A simplicial decomposition framework for large scale convex quadratic programmingMay 25 2017In this paper, we analyze in depth a simplicial decomposition like algorithmic framework for large scale convex quadratic programming. In particular, we first propose two tailored strategies for handling the master problem. Then, we describe a few techniques ... More
Searching for a continuum 4D field theory arising from a 5D non-abelian gauge theorySep 24 2013The anisotropic 5D SU(2) Yang-Mills model has been widely investigated on the lattice during the last decade. In the case where all dimensions are large in size, it was previously claimed that there is a new phase in the phase diagram, called the Layer ... More
Finite-temperature study of eight-flavor SU(3) gauge theoryJun 29 2015We present new lattice investigations of finite-temperature transitions for SU(3) gauge theory with Nf=8 light flavors. Using nHYP-smeared staggered fermions we are able to explore renormalized couplings $g^2 \lesssim 20$ on lattice volumes as large as ... More
Double parton scattering and the proton transverse structure at the LHCDec 11 2018We consider double parton distribution functions (dPDFs), essential quantities in double parton scattering (DPS) studies, which encode novel non perturbative insight on the partonic proton structure. We develop the formalism to extract this information ... More
Precision lattice test of the gauge/gravity duality at large-$N$Jun 15 2016We pioneer a systematic, large-scale lattice simulation of D0-brane quantum mechanics. The large-$N$ and continuum limits of the gauge theory are taken for the first time at various temperatures $0.4 \leq T \leq 1.0$. As a way to directly test the gauge/gravity ... More
Supergravity from D0-brane Quantum MechanicsJun 15 2016The gauge/gravity duality conjecture claims the equivalence between gauge theory and superstring/M-theory. In particular, the one-dimensional gauge theory of D0-branes and type IIA string theory should agree on properties of hot black holes. Type IIA ... More
Phase Structure Study of SU(2) Lattice Gauge Theory with 8 FlavorsOct 31 2014Dec 17 2014We present the investigation of the strong bare-coupling regime of SU(2) lattice gauge theory with 8 fermion flavors in the fundamental representation. The simulations are performed with unimproved staggered fermions and the plaquette gauge action. One ... More
Nuclear Parity Violation from Lattice QCDNov 06 2015The electroweak interaction at the level of quarks and gluons are well understood from precision measurements in high energy collider experiments. Relating these fundamental parameters to Hadronic Parity Violation in nuclei however remains an outstanding ... More
A special class of solutions in $F(R)$-gravityJan 31 2018Feb 23 2018We consider a special class of vacuum $F(R)$-modified gravity models. The form of their Lagrangian is such that the field equations are trivially satisfied when the Ricci scalar is constant. There are many interesting $F(R)$-models for inflation and dark ... More
Basel II for Physicists: A Discussion PaperJan 13 2005On June 26th, 2004, Central bank governors and the heads of bank supervisory authorities in the Group of Ten (G10) countries issued a press release and endorsed the publication of "International Convergence of Capital Measurement and Capital Standards: ... More
Quantum Bases in Uq(g)Sep 01 2008This paper is devoted to analize inside the infinitely many possible bases of Uq(g), same that can be considered "more equal then others". The element of selection has been a privileged relation with the bialgebra. A new parameter z' has been found that ... More
Regular Fredholm PairsApr 18 2014In this work it is introduced the notion of regular Fredholm pair, i.e. a Fredholm pair whose operators are regular. The main properties of these objects are studied, and what is more, they are entirely classified. Furthermore, the index of a Fredholm ... More
Interchain coherence of coupled Luttinger liquids at all orders in perturbation theoryNov 21 1997We analyze the problem of Luttinger liquids coupled via a single-particle hopping $\tp$ and introduce a systematic diagrammatic expansion in powers of $\tp$. An analysis of the scaling of the diagrams at each order allows us to determine the power-law ... More
Renormalization-Group Approach to a Three-Legs Fermionic LadderSep 24 1995Jun 24 1996We study the spin and charge phase diagram of a three-legs ladder (at zero temperature) as a function of fermion density and of transverse single-particle hopping by means of a Renormalization-Group analysis rigorously controlled in the weak-coupling ... More
Drazin spectra of Banach space operators and Banach algebra elementsJul 26 2013Given a Banach Algebra $A$ and $a\in A$, several relations among the Drazin spectrum of $a$ and the Drazin spectra of the multiplication operators $L_a$ and $R_a$ will be stated. The Banach space operator case will be also examined. Furthermore, a characterization ... More
On Cartan Joint SpectraJul 10 2014In this work several results regarding the Cartan version of the Taylor, the Slodkowski, the Fredholm, the split and the Fredholm split joint spectra will be studied.
Joint spectra of the tensor product representation of the direct sum of two solvable Lie algebrasAug 12 2016Given two complex Banach spaces $X_1$ and $X_2$, a tensor product $X_1\tilde{\otimes} X_2$ of $X_1$ and $X_2$ in the sense of [14], two complex solvable finite dimensional Lie algebras $L_1$ and $L_2$, and two representations $\rho_i\colon L_i\to {\rm ... More
Joint spectra and nilpotent Lie algebras of linear transformationsFeb 16 2016Given a complex nilpotent finite dimensional Lie algebra of linear transformations $L$, in a complex finite dimensional vector space $E$, we study the joint spectra $Sp(L,E)$, $\sigma_{\delta,k}(L,E)$ and $\sigma_{\pi,k}(L,E)$. We compute them and we ... More
On the joint spectra of the two dimensional Lie algebra of operators in Hilbert spacesMar 09 2016We consider the complex solvable non-commutative two dimensional Lie algebra $L$, $L=<y>\oplus <x>$, with Lie bracket $[x,y]=y$, as linear bounded operators acting on a complex Hilbert space $H$. Under the assumption $R(y)$ closed, we reduce the computation ... More
$L^p$-parabolic regularity and non-degenerate Ornstein-Uhlenbeck type operatorsMay 20 2014We prove $L^p$-parabolic a-priori estimates for $\partial_t u + \sum_{i,j=1}^d c_{ij}(t)\partial_{x_i x_j}^2 u = f $ on $R^{d+1}$ when the coefficients $c_{ij}$ are locally bounded functions on $R$. We slightly generalize the usual parabolicity assumption ... More
Optical spin orientation and depolarization in GeFeb 19 2013Optical spin orientation and depolarization phenomena in semiconductors are of overwhelming importance for the development of spin-optoelectronics. In this paper we employ Ge-based spin-photodiodes to investigate the room temperature spectral dependence ... More
Analytically Riesz operators and Weyl and Browder type theoremsJul 20 2015Several spectra of analytically Riesz operators will be characterized. These results will led to prove Weyl and Browder type theorems for the aforementioned class of operators.
Role of phytochemicals in the chemoprevention of tumorsMay 15 2016Phytochemicals are plant-derived secondary metabolites, which may exert many biological activities in humans, including anticancer properties. Although recent findings appear to support their role in cancer prevention and treatment, this issue is still ... More
Atomic scale nanoelectronics for quantum neuromorphic devices: comparing different materialsJun 03 2016I review the advancements of atomic scale nanoelectronics towards quantum neuromorphics. First, I summarize the key properties of elementary combinations of few neurons, namely long-- and short--term plasticity, spike-timing dependent plasticity (associative ... More
On the Validity of the EFT for Dark Matter Searches at the LHCSep 23 2014We review the limitations to the use of the effective field theory approach to study dark matter at the LHC. Due to the high energy reach, the low energy description breaks down, and may lead to incorrect results. The use of simplified models is suggested. ... More
A Gauss-Bonnet formula for moduli spaces of Riemann surfacesDec 18 2013We prove a Gauss-Bonnet theorem for (finite coverings of) moduli spaces of Riemann surfaces endowed with the McMullen metric. The proof uses properties of an exhaustion of moduli spaces by compact submanifolds with corners and the Gauss-Bonnet formula ... More
Landau levels on the 2D torus: a numerical approachApr 23 2008Apr 30 2008A numerical method is presented which allows to compute the spectrum of the Schroedinger operator for a particle constrained on a two dimensional flat torus under the combined action of a transverse magnetic field and any conservative force. The method ... More
Ideals with maximal local cohomology modulesDec 12 2002We characterize the class of ideals of a polynomial ring such that the hilbert series of their graded local cohomology modules is maximal.
Joint spectrum for quasi-solvable Lie algebras of operatorsMar 26 2016Given a complex Banach space $X$ and a joint spectrum for complex solvable finite dimensional Lie algebras of operators defined on $X$, we extend this joint spectrum to quasi-solvable Lie algebras of operators, and we prove the main spectral properties ... More
Space nutrition: the key role of nutrition in human space flightOct 02 2016From the basic impact of nutrient intake on health maintenance to the psychosocial benefits of mealtime, great advancements in nutritional sciences for support of human space travel have occurred over the past 60 years. Nutrition in space has many areas ... More
Pathwise uniqueness for singular SDEs driven by stable processesMay 23 2010Jun 02 2010We prove pathwise uniqueness for stochastic differential equations driven by non-degenerate symmetric $\alpha$-stable L\'evy processes with values in $\R^d$ having a bounded and $\beta$-H\"older continuous drift term. We assume $\beta > 1 - \frac{\alpha}{2} ... More
On the spectral set of a solvable Lie algebra of operatorsOct 30 2015Given $L$ a complex solvable finite dimensional Lie Algebra of operators acting on a Banach space $E$ and $\{ x_i\}_{1\le i\le n}$ a Jordan-H\"older basis of $ L$, we study the relation between $Sp(L,E)$ and $\Pi Sp(x_i)$.
Direct and inverse limits of normed modulesFeb 11 2019The aim of this note is to study existence and main properties of direct and inverse limits in the category of normed $L^0$-modules (in the sense of Gigli) over a metric measure space.
Finite Quantum Grand Canonical Ensemble and Temperature from Single Electron Statistics in a Mesoscopic DeviceJan 14 2010I present a theoretical model of a quantum statistical ensemble for which, unlike in conventional physics, the total number of particles is extremely small. The thermodynamical quantities are calculated by taking a small $N$ by virtue of the orthodicity ... More
The Nature of Time: from a Timeless Hamiltonian Framework to Clock Time of MetrologyJul 10 2009The problem of the Nature of Time is twofold: whether or not time is a fundamental quantity of Nature, and how does clock time of metrology emerge in the experimental description of dynamics. This work strongly supports the fundamental timelessness of ... More
Learning from Galileo's errorsJun 19 2012Four hundred years after its publication, Galileo's masterpiece Sidereus Nuncius is still a mine of useful information for historians of science and astronomy. In his short book Galileo reports a large amount of data that, despite its age, has not yet ... More
The evolution of massive black holes and their spins in their galactic hostsJan 27 2012Apr 16 2014[Abridged] [...] We study the mass and spin evolution of massive black holes within a semianalytical galaxy-formation model that follows the evolution of dark-matter halos along merger trees, as well as that of the baryonic components (hot gas, stellar ... More
Isolated spectral points and Koliha-Drazin invertible elements in quotient Banach algebras and homomorphism rangesMar 14 2014In this article poles, isolated spectral points, group, Drazin and Koliha-Drazin invertible elements in the context of quotient Banach algebras or in ranges of (not necessarily continuous) homomorphism between complex unital Banach algebras will be characterized ... More
The Drazin spectrum in Banach algebrasSep 19 2013Several basic properties of the Drazin spectrum in Banach algebras will be studied. As an application, some results on meromorphic Banach space operators will be obtained.
Reduction theory for mapping class groups and applications to moduli spacesJan 10 2008Let $S=S_{g,p}$ be a compact, orientable surface of genus $g$ with $p$ punctures and such that $d(S):=3g-3+p>0$. The mapping class group $\textup{Mod}_S$ acts properly discontinuously on the Teichm\"uller space $\mathcal T(S)$ of marked hyperbolic structures ... More
Crossover from Luttinger- to Fermi-liquid behavior in strongly anisotropic systems in large dimensionsMar 30 1999Jun 09 1999We consider the low-energy region of an array of Luttinger liquids coupled by a weak interchain hopping. The leading logarithmic divergences can be re-summed to all orders within a self-consistent perturbative expansion in the hopping, in the large-dimension ... More
Steady State Visually Evoked Potentials detection using a single electrode consumer-grade EEG device for BCI applicationsNov 15 2016Brain-Computer Interfaces (BCIs) implement a direct communication pathway between the brain of an user and an external device, as a computer or a machine in general. One of the most used brain responses to implement non-invasive BCIs is the so called ... More
Reducing the number of variables of a polynomialJul 26 2005In this paper, we consider two basic questions about presenting a homogeneous polynomial f: how many variables are needed for presenting f? How can one find a presentation of f involving as few variables as possible? We give a complete answer to both ... More
Denouement of a Wormhole-Brane EncounterAug 18 2009Higher-dimensional black holes have long been considered within the context of brane worlds. Recently, it was shown that the brane-world ethos also permits the consideration of higher-dimensional wormholes. When such a wormhole, preexisting in the bulk, ... More
Higher-Dimensional Bulk Wormholes and their Manifestations in Brane WorldsJan 04 2007There is nothing to prevent a higher-dimensional anti-de Sitter bulk spacetime from containing various other branes in addition to hosting our universe, presumed to be a positive-tension 3-brane. In particular, it could contain closed, microscopic branes ... More
Proceedings 18th international workshop on Cellular Automata and Discrete Complex Systems and 3rd international symposium Journées Automates CellulairesAug 13 2012This volume contains the proceedings of the 18th International workshop AUTOMATA and the 3rd international symposium JAC. AUTOMATA workshop series aims at gathering researchers from all over the world working in fundamental aspects of cellular automata ... More
Lift in the 3-sphere of knots and links in lens spacesDec 04 2013An important geometric invariant of links in lens spaces is the lift in the 3-sphere of a link $L$ in $L(p,q)$, that is the counterimage $\widetilde L$ of $L$ under the universal covering of $L(p,q)$. If lens spaces are defined as a lens with suitable ... More
Inflation at the TipFeb 20 2008Feb 28 2008We study the motion of a (space filling) D3-brane at the tip of a warped deformed conifold, looking for inflationary trajectories. In our setup no anti D3-brane is present and the inflaton potential is induced by threshold corrections to the superpotential. ... More
Optimal higher-dimensional Dehn functions for some CAT(0) latticesMay 22 2012Let $X=S\times E \times B$ be the metric product of a symmetric space $S$ of noncompact type, a Euclidean space $E$ and a product $B$ of Euclidean buildings. Let $\Gamma$ be a discrete group acting isometrically and cocompactly on $X$. We determine a ... More
On weak uniqueness for some degenerate SDEs by global $L^p$ estimatesMay 30 2013Sep 02 2014We prove uniqueness in law for possibly degenerate SDEs having a linear part in the drift term. Diffusion coefficients corresponding to non-degenerate directions of the noise are assumed to be continuous. When the diffusion part is constant we recover ... More
Landau levels on a torusJul 18 2000Landau levels have represented a very rich field of research, which has gained widespread attention after their application to quantum Hall effect. In a particular gauge, the holomorphic gauge, they give a physical implementation of Bargmann's Hilbert ... More
Quantum algebras and Lie groupsNov 17 1992Nov 21 1992Lie groups and quantum algebras are connected through their common universal enveloping algebra. The adjoint action of Lie group on its algebra is naturally extended to related q-algebra and q-coalgebra. In such a way, quantum structure can be dealt more ... More
Joint spectra of representations of Lie algebras by compact operatorsMay 15 2014Given $X$ a complex Banach space, $L$ a complex nilpotent finite dimensional Lie algebra, and $\rho\colon L\to L(X)$, a representation of $L$ in $X$ such that $\rho (l)\in K(X)$ for all $l\in L$, the Taylor, the Slodkowski, the Fredholm, the split and ... More
The Drazin spectrum of tensor product of Banach algebra elements and elementary operatorsApr 11 2014Given unital Banach algebras $A$ and $B$ and elements $a\in A$ and $b\in B$, the Drazin spectrun of $a\otimes b\in A\overline{\otimes} B$ will be fully characterized, where $A\overline{\otimes} B$ is a Banach algebra that is the completion of $A\otimes ... More
The role of Dirac equations in the classical mechanics of the relativistic topAug 24 2008Jul 15 2011A rigorous \textit{ab initio} derivation of the (square of) Dirac's equation for a single particle with spin is presented. The general Hamilton-Jacobi equation for the particle expressed in terms of a background Weyl's conformal geometry is found to be ... More
On the Theory of Collisions between Atoms and Electrically Charged ParticlesMay 09 2002In the fall of 1924, Enrico Fermi visited Paul Ehrenfest at Leyden on a 3-month fellowship from the International Education Board (IEB). Fermi was 23 years old. In his trip report to the IEB, Fermi says he learned a lot about cryogenics and worked on ... More
From the long jump random walk to the fractional LaplacianJan 21 2009This note illustrates how a simple random walk with possibly long jumps is related to fractional powers of the Laplace operator. The exposition is elementary and self-contained.
Characterizations of Fredholm pairs and chains in Hilbert spacesApr 03 2014In this work characterizations of Fredholm pairs and chains of Hilbert space operators are given. Following a well-known idea of several variable operator theory in Hilbert spaces, the aforementioned objects are characterized in terms of Fredholm linear ... More
Tensor products and the semi-Browder joint spectraMay 21 2016Given two complex Banach spaces $X_1$ and $X_2$, a tensor product of $X_1$ and $X_2$, $X_1\tilde{\otimes}X_2$, in the sense of J. Eschmeier ([5]), and two finite tuples of commuting operators, $S=(S_1,\ldots ,S_n)$ and $T=(T_1,\ldots ,T_m)$, defined on ... More
On the joint spectral radius of a nilpotent Lie algebra of matricesApr 29 2016For a complex nilpotent finite dimensional Lie algebra of matrices,and a Jordan-H\"older basis of it, we prove a spectral radius formula which extends a well-known result for commuting matrices.
A class of CTRWs: Compound fractional Poisson processesMar 03 2011This chapter is an attempt to present a mathematical theory of compound fractional Poisson processes. The chapter begins with the characterization of a well-known L\'evy process: The compound Poisson process. The semi-Markov extension of the compound ... More
Davie's type uniqueness for a class of SDEs with jumpsSep 24 2015A result of A.M. Davie [Int. Math. Res. Not. 2007] states that a multidimensional stochastic equation $dX_t = b(t, X_t)\,dt + dW_t$, $X_0=x$, driven by a Wiener process $W= (W_t)$ with a coefficient $b$ which is only bounded and measurable has a unique ... More
Factorizations of EP Banach space operators and EP Banach algebra elementsJun 18 2013EP Banach space operators and EP Banach algebra elements are characterized using different kinds of factorizations. The results obtained generalize well-known characterizations of EP matrices, EP Hilbert space operators and EP $C^*$-algebra elements. ... More
Dual properties and joint spectra for solvable Lie algebras of operatorsOct 04 2015Given $L$ a solvable Lie Algebra of operators acting on a Banach space $E$, we study the action of the opposite algebra of $L$, $L'$, on $E^*$. Moreover, we extend S{\l}odkowski joint spectra, $\sigma_{\delta,k}$, $\sigma_{\pi,k}$, and we study its usual ... More
Tensor products and joint spectra for solvable Lie algebras of operatorsJan 09 2016Given two complex Hilbert spaces, $H_1$ and $H_2$, and two complex solvable finite dimensional Lie algebras of operators, $L_1$ and $L_2$, such that $L_i$ acts on $H_i$ (i= 1,2), the joint spectrum of the Lie algebra $L_1\times L_2$, which acts on $H_1\overline\otimes ... More
Lattice study for conformal windows of SU(2) and SU(3) gauge theories with fundamental fermionsNov 06 2015We present our investigation of SU(2) gauge theory with 8 flavours, and SU(3) gauge theory with 12 flavours. For the SU(2) case, at strong bare coupling, $\beta \lesssim 1.45$, the distribution of the lowest eigenvalue of the Dirac operator can be described ... More
Two-nucleon scattering in multiple partial wavesNov 06 2015We determine scattering phase shifts for S,P,D, and F partial wave channels in two-nucleon systems using lattice QCD methods. We use a generalization of Luscher's finite volume method to determine infinite volume phase shifts from a set of finite volume ... More
Two-Nucleon Higher Partial-Wave Scattering from Lattice QCDAug 04 2015We present a determination of nucleon-nucleon scattering phase shifts for l>=0. The S,P,D and F phase shifts for both the spin-triplet and spin-singlet channels are computed for the first time with lattice Quantum ChromoDynamics. This required the design ... More
A Two-Stage Active-Set Algorithm for Bound-Constrained OptimizationJul 28 2016Sep 23 2016In this paper, we describe a two-stage method for solving optimization problems with bound constraints. It combines the active-set estimate described in [Facchinei and Lucidi, 1995] with a modification of the nonmonotone line search framework recently ... More
A momentum-space representation of Green's functions with modified dispersion on ultra-static space-timeSep 17 2007Oct 05 2007We consider the Green's functions associated to a scalar field propagating on a curved, ultra-static background, in the presence of modified dispersion relations. The usual proper-time deWitt-Schwinger procedure to obtain a series representation of the ... More
A Two-Stage Active-Set Algorithm for Bound-Constrained OptimizationJul 28 2016Oct 06 2016In this paper, we describe a two-stage method for solving optimization problems with bound constraints. It combines the active-set estimate described in [Facchinei and Lucidi, 1995] with a modification of the nonmonotone line search framework recently ... More
The entropy of an acoustic black hole in Bose-Einstein condensatesJun 23 2011Nov 11 2011We compute the entanglement entropy associated to the Hawking emission of a $(1+1)$-dimensional acoustic black hole in a Bose-Einstein condensate. We use the brick wall model proposed by 't Hooft, adapted to the momentum space, in order to tackle the ... More
A momentum-space representation of Green's functions with modified dispersion relations on general backgroundsMar 26 2008Jun 04 2008We consider the problem of calculating the Green's functions associated to a massive scalar field with modified dispersion relations. We analyze the case when dispersion is modified by higher derivative spatial operators acting on the field orthogonally ... More
Mimicking dark matter in Horndeski gravityAug 12 2016Since the rediscovery of Horndeski gravity, a lot of work has been devoted to the exploration of its properties, especially in the context of dark energy. However, one sector of this theory, namely the one containing the coupling of the Einstein tensor ... More
Higgs Dark EnergyApr 02 2014Jan 20 2015We study the classical dynamics of a non-abelian Higgs theory coupled to gravity in an isotropic and homogeneous Universe. For non-minimal coupling, this theory leads to a model of cosmic inflation that is very attractive due to its simplicity and consistency ... More
Self-T-Dual Brane CosmologyOct 23 2006Oct 24 2006We show how T-duality can be implemented with brane cosmology. As a result, we obtain a smooth bouncing cosmology with features similar to the ones of the pre-Big Bang scenario. Also, by allowing T-duality transformations along the time-like direction, ... More
A new approach to non-commutative inflationAug 13 2009Mar 24 2011We propose an inflationary scenario inspired by a recent formulation, in terms of coherent states, of non-commutative quantum field theory. We consider the semiclassical Einstein equations, and we exploit the ultraviolet finiteness of the non-commutative ... More
Superluminal dispersion relations and the Unruh effectFeb 05 2008May 26 2008In the context of quantum gravity phenomenology, we study the Unruh effect in the presence of superluminal dispersion relations. In particular, we estimate the response function and the probability rate for an accelerated detector coupled to a massless ... More
Toroidal Black Holes and T-dualityAug 03 2002Aug 19 2002We consider the toroidal black holes that arise as a generalization of the AdS_5 times S^5 solution of type IIB supergravity. The symmetries of the horizon space allow T-duality transformations that can be exploited to generate new inequivalent black ... More