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Uniqueness of $\mathcal{N}=2$ and $3$ pure supergravities in 4DFeb 08 2018After proving the impossibility of consistent non-minimal coupling of a real Rarita-Schwinger gauge field to electromagnetism, we re-derive the necessity of introducing the graviton in order to couple a complex Rarita-Schwinger gauge field to electromagnetism, ... More

Large Graph Analysis in the GMine SystemMay 28 2015Current applications have produced graphs on the order of hundreds of thousands of nodes and millions of edges. To take advantage of such graphs, one must be able to find patterns, outliers and communities. These tasks are better performed in an interactive ... More

Review on qudits production and their application to Quantum Communication and Studies on Local RealismNov 08 2007Nov 16 2007The codification in higher dimensional Hilbert Spaces (whose logical basis states are dubbed qudits in analogy with bidimensional qubits) presents various advantages both for Quantum Information applications and for studies on Foundations of Quantum Mechanics. ... More

Combining Visual Analytics and Content Based Data Retrieval Technology for Efficient Data AnalysisJun 25 2015One of the most useful techniques to help visual data analysis systems is interactive filtering (brushing). However, visualization techniques often suffer from overlap of graphical items and multiple attributes complexity, making visual selection inefficient. ... More

Quantum bright solitons in a quasi-one-dimensional optical latticeJan 31 2014Jun 04 2014We study a quasi-one-dimensional attractive Bose gas confined in an optical lattice with a superimposed harmonic potential by analyzing the effective one-dimensional Bose-Hubbard Hamiltonian of the system. In order to have a reliable description of the ... More

Safe Recursion on Notation into a Light Logic by LevelsMay 04 2010We embed Safe Recursion on Notation (SRN) into Light Affine Logic by Levels (LALL), derived from the logic L4. LALL is an intuitionistic deductive system, with a polynomial time cut elimination strategy. The embedding allows to represent every term t ... More

SuperGraph VisualizationJun 15 2015Given a large social or computer network, how can we visualize it, find patterns, outliers, communities? Although several graph visualization tools exist, they cannot handle large graphs with hundred thousand nodes and possibly million edges. Such graphs ... More

Extending a system in the calculus of structures with a self-dual quantifierDec 18 2012We recall that SBV, a proof system developed under the methodology of deep inference, extends multiplicative linear logic with the self-dual non-commutative logical operator Seq. We introduce SBVQ that extends SBV by adding the self-dual quantifier Sdq. ... More

Communication, and concurrency with logic-based restriction inside a calculus of structuresDec 19 2012It is well known that we can use structural proof theory to refine, or generalize, existing paradigmatic computational primitives, or to discover new ones. Under such a point of view we keep developing a programme whose goal is establishing a correspondence ... More

Natural Warm InflationJul 18 2011Sep 06 2011We derive the requirements that a generic axion-like field has to satisfy in order to play the role of the inflaton field in the warm inflation scenario. Compared to the parameter space in ordinary natural inflation models, we find that the parameter ... More

Conformal metrics on $\R^{2m}$ with constant Q-curvatureMay 06 2008We study the conformal metrics on $\R^{2m}$ with constant Q-curvature $Q$ having finite volume, particularly in the case $Q\leq 0$. We show that when $Q<0$ such metrics exist in $\R^{2m}$ if and only if $m>1$. Moreover we study their asymptotic behavior ... More

Quantization for the prescribed Q-curvature equation on open domainsMar 21 2010We discuss compactness, blow-up and quantization phenomena for the prescribed $Q$-curvature equation $(-\Delta)^m u_k=V_ke^{2mu_k}$ on open domains of $\R{2m}$. Under natural integral assumptions we show that when blow-up occurs, up to a subsequence $$\lim_{k\to ... More

Condensate formation with three-component ultracold fermionsMar 05 2011We investigate the formation of Bose-Einstein condensation and population imbalance in a three-component Fermi superfluid by increasing the U(3) invariant attractive interaction. We consider the system at zero temperature in three dimensions and also ... More

Generalized nonpolynomial Schrodinger equations for matter waves under anisotropic transverse confinementJul 07 2009Starting from the three-dimensional Gross-Pitaevskii equation we derive a 1D generalized nonpolynomial Schrodinger equation, which describes the dynamics of Bose-Einstein condensates under the action of a generic potential in the longitudinal axial direction ... More

Ideal Quantum Gases in D-dimensional Space and Power-law PotentialsAug 22 2000We investigate ideal quantum gases in D-dimensional space and confined in a generic external potential by using the semiclassical approximation. In particular, we derive density of states, density profiles and critical temperatures for Fermions and Bosons ... More

Chaotic Oscillations in Finite Quantum Systems: Trapped Bose-Einstein CondensatesJun 22 1999We discuss the recently achieved Bose-Einstein condensation for alkali-metal atoms in magnetic traps. The theoretically predicted low-energy collective oscillations of the condensate have been experimentally confirmed by laser imaging techniques. We show ... More

Quantum Chaos in a Yang-Mills-Higgs SystemJun 12 1997We study the energy fluctuations of a spatially homogeneous SU(2) Yang-Mills-Higgs system. In particular, we analyze the nearest-neighbour spacing distribution which shows a Wigner-Poisson transition by increasing the value of the Higgs field in the vacuum. ... More

Low-temperature thermodynamics of the unitary Fermi gas: superfluid fraction, first sound and second soundNov 22 2010We investigate the low-temperature thermodynamics of the unitary Fermi gas by introducing a model based on the zero-temperature spectra of both bosonic collective modes and fermonic single-particle excitations. We calculate the Helmholtz free energy and ... More

Condensate fraction in metallic superconductors and ultracold atomic vaporsMar 19 2010We investigate the condensate density and the condensate fraction of conduction electrons in weak-coupling superconductors by using the BCS theory and the concept of off-diagonal-long-range-order. We discuss the analytical formula of the zero-temperature ... More

On the homological dimension of o-minimal and subanalytic sheavesNov 09 2009Here we prove that the homological dimension of the category of sheaves on a topological space satisfying some suitable conditions is finite. In particular, we find conditions to bound the homological dimension of o-minimal and subanalytic sheaves.

Boundaries of analytic varietiesNov 05 2012We prove that every smooth CR manifold $M\subset\subset \C^n$, of hypersurface type, has a complex strip-manifold extension in $\C^n$. If $M$ is, in addition, pseudoconvex-oriented, it is the "exterior" boundary of the strip. In turn, the strip extends ... More

Splitting in the K-theory localization sequence of number fieldsFeb 15 2010Feb 25 2010Let p be a rational prime and let F be a number field. Then, for each i>0, there is a short exact localization sequence for K_{2i}(F). If p is odd or F is nonexceptional, we find necessary and sufficient conditions for this exact sequence to split: these ... More

On Morphic Actions and Integrability of LA-GroupoidsFeb 12 2009Lie theory for the integration of Lie algebroids to Lie groupoids, on the one hand, and of Poisson manifolds to symplectic groupoids, on the other, has undergone tremendous developements in the last decade, thanks to the work of Mackenzie-Xu, Moerdijk-Mrcun, ... More

O'Raifeartaigh models with spontaneous R-symmetry breakingOct 12 2007O'Raifeartaigh models with general R-charge assignments can have vacua where both supersymmetry and R-symmetry are spontaneously broken. Most of these vacua are metastable because the potential shows a runaway behaviour. We explain the relation between ... More

Microlocalization of subanalytic sheavesFeb 15 2007Jun 24 2010In this paper we define specialization and microlocalization for subanalytic sheaves. Applying these functors to the sheaves of tempered and Whytney holomorphic functions we get a unifying description of tempered and formal microlocalization using the ... More

Weak complementarity from discrete symmetriesOct 15 2009The neutrino oscillation data find a good approximation in the so-called tri-bimaximal pattern. Recently a paper appeared showing that also the bimaximal pattern, which is already ruled out by the measurements, could be a very good starting point in order ... More

Neutrino Masses and Mixings from Continuous SymmetriesNov 11 2014Flavour symmetries are fundamental tools in the search for an explanation to the flavour puzzle: fermion mass hierarchies, the neutrino mass ordering, the differences between the mixing matrices in the quark and lepton sector, can all find an explanation ... More

Geometry and topology of turbulence in active nematicsSep 04 2014Aug 03 2015The problem of low Reynolds number turbulence in active nematic fluids is theoretically addressed. Using numerical simulations I demonstrate that an incompressible turbulent flow, in two-dimensional active nematics, consists of an ensemble of vortices ... More

Softly Constrained FilmsApr 03 2013The shape of materials is often subject to a number of geometric constraints that limit the size of the system or fix the structure of its boundary. In soft and biological materials, however, these constraints are not always hard, but are due to other ... More

The lift-up effect: the linear mechanism behind transition and turbulence in shear flowsMar 19 2014The formation and amplification of streamwise velocity perturbations induced by cross-stream disturbances is ubiquitous in shear flows. This disturbance growth mechanism, so neatly identified by Ellingsen and Palm in 1975, is a key process in transition ... More

Least-Order Torsion-Gravity for Fermion Fields, and the Non-Linear Potentials in the Standard ModelsJan 28 2014Dec 15 2014We will consider the least-order torsional completion of gravity for a spacetime filled with fermionic Dirac matter fields, and we study the effects of the background-induced non-linear potentials for the matter field themselves in view of their effects ... More

Conformal Standard ModelJul 03 2011Apr 10 2014In recent papers we have constructed the conformal theory of metric-torsional gravitation, and in this paper we shall include the gauge fields to study the conformal U(1) X SU(2) Standard Model; we will show that the metric-torsional degrees of freedom ... More

Massless Fermion Mixing for Semispinorial Torsional InteractionDec 17 2010Mar 19 2012We consider a geometric approach to field theory in which torsion is present in the matter field equations, and we develop the consequences of the torsion-spin coupling for a pair of single-handed spinors; we show these interactions to have the structure ... More

The most general cosmological dynamics for ELKO Matter FieldsNov 07 2010Sep 19 2011Not long ago, the definition of eigenspinors of charge-conjugation belonging to a special Wigner class has lead to the unexpected theoretical discovery of a form of matter with spin 1/2 and mass dimension 1, called ELKO matter field; ELKO matter fields ... More

Leptonic Electroweak Spin-Torsion InteractionsJun 21 2010Aug 05 2011In this paper we consider the most general field equations for a system of two fermions of which one single-handed, showing that the spin-torsion interactions among these spinors have a structure identical to that of the electroweak forces among leptons; ... More

Metric Solutions in Torsionless Gauge for Vacuum Conformal GravityApr 26 2011Apr 10 2014In a recent paper we have established the form of the metric-torsional conformal gravitational field equations, and in the present paper we study their vacuum configurations; we will consider a specific situation that will enable us to look for the torsionless ... More

On geometric relativistic foundations of matter field equations and plane wave solutionsJun 18 2010Jun 05 2012In this paper, we start from the geometric relativistic foundations to define the basis upon which matter field theories are built, and their wave solutions are investigated, finding that they display repulsive interactions able to reproduce the exclusion ... More

On the consistency of Constraints in Matter Field TheoriesJul 03 2009Jun 19 2012We consider how the principles of causality and equivalence restrict the background in which matter field theories are defined; those constraints develop in restrictions for these matter field theories: the simplest matter field theory aside, all other ... More

Warping the Kähler potential of F-theory/IIB flux compactificationsNov 10 2014Mar 12 2015We identify the low-energy K\"ahler potential of warped F-theory/IIB flux compactifications whose light spectrum includes universal, K\"ahler, axionic and mobile D3-brane moduli. The derivation is based on four-dimensional local superconformal symmetry ... More

Supersymmetric D-branes on flux backgroundsJan 10 2007Mar 14 2007Several aspects concerning the physics of D-branes in Type II flux compactifications preserving minimal N=1 supersymmetry in four dimensions are considered. It is shown how these vacua are completely characterized in terms of properly defined generalized ... More

Superstrings in AdSApr 13 2011Feb 12 2012This is a comprehensive review of the worldsheet techniques for the quantization of type IIB superstring theory on the AdS_5 x S^5 background, using the pure spinor formalism. Particular emphasis is devoted to AdS/CFT applications, with several examples ... More

Fitness landscapes and evolutionMay 02 1995The concept of fitness is introduced, and a simple derivation of the Fundamental Theorem of Natural Selection (which states that the average fitness of a population increases if its variance is nonzero) is given. After a short discussion of the adaptative ... More

Moser-Trudinger inequalities for singular Liouville systemsOct 18 2014Nov 17 2015In this paper we prove a Moser-Trudinger inequality for the Euler-Lagrange functional of a general singular Liouville system. We characterize the values of the parameters which yield coercivity for the functional and we give necessary conditions for boundedness ... More

Firm size distribution in Italy and employment protectionDec 02 2014The number of Italian firms in function of the number of workers is well approximated by an inverse power law up to 15 workers but shows a clear downward deflection beyond this point, both when using old pre-1999 data and when using recent (2014) data. ... More

The dependence of cosmological parameters estimated from the microwave background on non-gaussianityJul 27 2001The estimation of cosmological parameters from cosmic microwave experiments has almost always been performed assuming gaussian data. In this paper the sensitivity of the parameter estimation to different assumptions on the probability distribution of ... More

Scaling solutions in general non-minimal coupling theoriesApr 09 1999A class of generalized non-minimal coupling theories is investigated, in search of scaling attractors able to provide an accelerated expansion at the present time. Solutions are found in the strong coupling regime and when the coupling function and the ... More

Non-Gaussian Chi-squared method with the multivariate Edgeworth expansionOct 13 1998I present here a generalization of the maximum likelihood method and the $\chi^2$ method to the cases in which the data are {\it not} assumed to be Gaussian distributed. The method, based on the multivariate Edgeworth expansion, can find several astrophysical ... More

Coupled QuintessenceAug 03 1999A new component of the cosmic medium, a light scalar field or ''quintessence '', has been proposed recently to explain cosmic acceleration with a dynamical cosmological constant. Such a field is expected to be coupled explicitely to ordinary matter, unless ... More

Proper stacksJun 19 2006Nov 14 2006We generalize the notion of proper stack introduced by Kashiwara and Schapira to the case of a general site, and we prove that a proper stack is a stack.

Dimension reduction for model-based clusteringAug 07 2015We introduce a dimension reduction method for visualizing the clustering structure obtained from a finite mixture of Gaussian densities. Information on the dimension reduction subspace is obtained from the variation on group means and, depending on the ... More

A dangerous irrelevant UV-completion of the composite HiggsJun 01 2015Jul 10 2016One of the most challenging hurdles to the construction of realistic composite Higgs models is the generation of Yukawa couplings for the Standard Model fermions. This problem can be successfully addressed in approximate conformal theories that admit ... More

Fractional perimeter from a fractal perspectiveMar 19 2016Following \cite{Visintin}, we exploit the fractional perimeter of a set to give a definition of fractal dimension for its measure theoretic boundary. We calculate the fractal dimension of sets which can be defined in a recursive way and we give some examples ... More

Light sterile neutrinos from a late phase transitionJul 14 2016Light sterile neutrinos represent a well-motivated extension of the 3-neutrino paradigm. However, the impressive agreement between standard cosmology and data casts doubts on their existence. Here we present a class of scenarios that robustly avoids this ... More

The anomalous dimension of spin-1/2 baryons in many flavors QCDJul 10 2016We derive the anomalous dimension of spin-1/2 baryon operators in QCD at leading 1/Nf order. Within this approximation the complication resulting from the mixing with an infinite number of evanescent operators can be easily bypassed.

Combination of measurements and the BLUE methodOct 03 2016The most accurate method to combine measurement from different experiments is to build a combined likelihood function and use it to perform the desired inference. This is not always possible for various reasons, hence approximate methods are often convenient. ... More

Fractional Perimeter and Nonlocal Minimal SurfacesAug 25 2015This Master's thesis presents a study of the basic properties of the s-fractional perimeter and of the regularity theory of the corresponding s-minimal sets. In particular, we give full detailed proofs for all the Theorems contained in the article "Nonlocal ... More

Inapproximability of Combinatorial Optimization ProblemsSep 24 2004We survey results on the hardness of approximating combinatorial optimization problems.

Existence of affine pavings for varieties of partial flags associated to nilpotent elementsMay 15 2013May 19 2014The flag variety of a complex reductive linear algebraic group G is by definition the quotient G/B by a Borel subgroup. It can be regarded as the set of Borel subalgebras of Lie(G). Given a nilpotent element e in Lie(G), one calls Springer fiber the subvariety ... More

Characterizations of BMO through commutators of bilinear singular integral operatorsOct 16 2014Dec 09 2014In this paper we characterize BMO in terms of the boundedness of commutators of various bilinear singular integral operators with pointwise multiplication. In particular, we study commutators of a wide class of bilinear operators of convolution type, ... More

Self-Dual Soliton Solution in a Generalized Jackiw-Pi ModelJul 31 2012Aug 30 2012We consider a generalization of Jackiw-Pi model by introducing a nonstandard kinetic term. We present a Bogomolnyi framework for this theory and as a particular case we show that the Bogomolnyi equations of Chern-Simons Higgs theory can be obtained. Finally, ... More

Inclusive searches for SUSY at CMSSep 12 2014Multiple searches for supersymmetry have been performed at the CMS experiment. Of these, inclusive searches aim to remain as sensitive as possible to the widest range of potential new physics scenarios. The results presented in this talk use the latest ... More

Constraining chameleon models with cosmologyMar 17 2014Jan 04 2015Chameleon fields may modify gravity on cluster scales while recovering general relativity locally. This article reviews signatures of chameleon modifications in the nonlinear cosmological structure, comparing different techniques to model them, summarising ... More

A note on vortices from Lorentz-violating modelsNov 18 2013Apr 12 2014We consider two self-dual abelian Higgs systems obtained from Lorentz breaking symmetry models by dimensional reduction. For the first model, we show that the self-dual equations are identical to those of Nielsen-Olesen vortices. Also, we show that our ... More

A simple yet efficient algorithm for multiple kernel learning under elastic-net constraintsJun 29 2015Jan 13 2016This report presents an algorithm for the solution of multiple kernel learning (MKL) problems with elastic-net constraints on the kernel weights.

Low energy cosmic ray positron fraction explained by charge-sign dependent solar modulationNov 29 2012Jan 24 2013We compute cosmic ray (CR) nuclei, proton, antiproton, electron and positron spectra below 1 TeV at Earth by means of a detailed transport description in the galaxy and in the solar system. CR spectra below 10 GeV are strongly modified by charge-sign ... More

The L^p-continuity of the wave operators for the three dimensional Schroedinger operatorJan 04 2007May 14 2007This paper has been withdrawn, because of an error in the proof of the main Theorem

Integrability and reduction of Poisson group actionsOct 30 2007Nov 01 2007In this paper we study Poisson actions of complete Poisson groups, without any connectivity assumption or requiring the existence of a momentum map. For any complete Poisson group $G$ with dual $G^\star$ we obtain a suitably connected integrating symplectic ... More

Statistical geometry of random weave statesJan 19 2001I describe the first steps in the construction of semiclassical states for non-perturbative canonical quantum gravity using ideas from classical, Riemannian statistical geometry and results from quantum geometry of spin network states. In particular, ... More

Neutrinos Oscillations with Long-Base-Line Beams (Past, Present and very near Future)Jun 24 2010We overview the status of the studies on neutrino oscillations with accelerators at the present running experiments. Past and present results enlighten the path towards the observation of massive neutrinos and the settling of their oscillations. The very ... More

Elastic Z^0 production at HERAOct 13 2014The production of $Z^{0}$ bosons in the reaction $eparrow eZ^{0}p^{(*)}$, where $p^{(*)}$ stands for a proton or a low-mass nucleon resonance, has been studied in $ep$ collisions at HERA using the ZEUS detector. The analysis is based on a data sample ... More

Monopole-Antimonopole Correlation Functions in 4D U(1) Gauge TheoryMar 24 2006We study the two-point correlator of a modified Confined-Coulomb transition order parameter in four dimensional compact U(1) lattice gauge theory with Wilson action. Its long distance behavior in the confined phase turns out to be governed by a single ... More

Local aspects of free open bosonic string field theoryDec 01 2008We show that strictly local observables with arbitrarily small support in space-time exist in covariant free open bosonic string field theory. The main ingredient of the proof is a modified version of the well known DDF operators, which we rigourously ... More

Star Operation in Quantum MechanicsJul 06 2000Jul 21 2000We outline the description of Quantum Mechanics with noncommuting coordinates within the framework of star operation. We discuss simple cases of integrability.

A note on the Bruhat decomposition of semisimple Lie groupsJul 28 2008Let a split element of a connected semisimple Lie group act on one of its flag manifolds. We prove that each connected set of fixed points of this action is itself a flag manifold. With this we can obtain the generalized Bruhat decomposition of a semisimple ... More

Spherical Schrödinger Hamiltonians: Spectral Analysis and Time DecayNov 15 2016In this survey, we review recent results concerning the canonical dispersive flow $e^{itH}$ led by a Schr\"odinger Hamiltonian $H$. We study, in particular, how the time decay of space $L^p$-norms depends on the frequency localization of the initial datum ... More

B2 and G2 Toda systems on compact surfaces: a variational approachDec 23 2015Dec 25 2015We consider the B2 and G2 Toda systems on compact surfaces. We attack the problem using variational techniques. We get existence and multiplicity of solutions under a topological assumption on the surface and some generic conditions on the parameters. ... More

Stokes paradox in electronic Fermi liquidsDec 02 2016The Stokes paradox is the statement that in a viscous two dimensional fluid, the "linear response" problem of fluid flow around an obstacle is ill-posed. We present a simple consequence of this paradox in the hydrodynamic regime of a Fermi liquid of electrons ... More

Measure contraction properties of Carnot groupsOct 20 2015May 20 2016We prove that any corank 1 Carnot group of dimension $k+1$ equipped with a left-invariant measure satisfies the $\mathrm{MCP}(K,N)$ if and only if $K \leq 0$ and $N \geq k+3$. This generalizes the well known result by Juillet for the Heisenberg group ... More

On Some Manipulations with Fuzzy ProcessesMay 29 2009The paper starts from the observation on the complexity of the manipulation of fuzzy processes that increases very rapidly with the extents of the processes representation. Therefore, a productive approach is to divide the problem into smaller parts, ... More

From Lock Freedom to Progress Using Session TypesDec 10 2013Inspired by Kobayashi's type system for lock freedom, we define a behavioral type system for ensuring progress in a language of binary sessions. The key idea is to annotate actions in session types with priorities representing the urgency with which such ... More

Linear lambda Calculus with Explicit Substitutions as Proof-Search in Deep InferenceNov 16 2010May 26 2011SBV is a deep inference system that extends the set of logical operators of multiplicative linear logic with the non commutative operator Seq. We introduce the logical system SBVr which extends SBV by adding a self-dual atom-renaming operator to it. We ... More

Cauchy-Kowaleskaya-Kashiwara theorem with growth conditionsApr 03 2008We prove the Cauchy-Kowaleskaya-Kashiwara theorem for holomorphic functions with growth conditions.

A Discussion on the Heisenberg Uncertainty Principle from the Perspective of Special RelativityJan 09 2015Sep 16 2016In this note, we consider the implications of the Heisenberg uncertainty principle (HUP) when computing uncertainties that affect the main dynamical quantities, from the perspective of special relativity. Using the well-known formula for propagating statistical ... More

Conformal metrics on R^{2m} with constant Q-curvature and large volumeFeb 06 2012We study conformal metrics on R^{2m} with constant Q-curvature and finite volume. When m=3 we show that there exists V* such that for any V\in [V*,\infty) there is a conformal metric g on R^{6} with Q_g = Q-curvature of S^6, and vol(g)=V. This is in sharp ... More

Classification of solutions to the higher order Liouville's equation on R^{2m}Jan 17 2008We classify the solutions to the equation (- \Delta)^m u=(2m-1)!e^{2mu} on R^{2m} giving rise to a metric g=e^{2u}g_{R^{2m}} with finite total $Q$-curvature in terms of analytic and geometric properties. The analytic conditions involve the growth rate ... More

Discrete bright solitons in Bose-Einstein condensates and dimensional reduction in quantum field theoryNov 01 2014Nov 04 2014We first review the derivation of an effective one-dimensional (1D) discrete nonpolynomial Schr\"odinger equation from the continuous 3D Gross-Pitaevskii equation with transverse harmonic confinement and axial periodic potential. Then we study the bright ... More

Two-dimensional quasi-ideal Fermi gas with Rashba spin-orbit couplingNov 16 2013Nov 22 2013We investigate the zero-temperature properties of a quasi-ideal Fermi gas with Rashba spin-orbit coupling. We find that the spin-orbit term strongly affects the speeds of zero sound and first sound in the Fermi gas, due to the presence of a third-order ... More

Contact intensity and extended hydrodynamics in the BCS-BEC crossoverOct 12 2012In the first part of this chapter we analyze the contact intensity $C$, which has been introduced by Tan [Ann. Phys. 323, 2952 (2008)] and appears in several physical observables of the strongly correlated two-component Fermi gas. We calculate the contact ... More

Supersonic and subsonic shock waves in the unitary Fermi gasOct 03 2011We investigate shock waves in the unitary Fermi gas by using the zero-temperature equations of superfluid hydrodynamics. We obtain analytical solutions for the dynamics of a localized perturbation of the uniform gas. These supersonic bright and subsonic ... More

Triaxial Bright Solitons in Bose-Condensed Atomic VaporsJul 25 2004The properties of triaxial bright solitons (TBSs) made of attractive Bose-Einstein condensed atoms under transverse anisotropic harmonic confinement are investigated by using a variational approach. We show that these metastable TBSs change their shape ... More

Statistical Mechanics of a Trapped Bose-Einstein CondensateMar 26 1998Bose-Einstein condensation (BEC) in a gas has now been achieved. Alkali atoms ($^{87}Rb$, $^{23}Na$ and $^{7}Li$) have been cooled to the point of condensation (temperature of 100 nK) using laser cooling and trapping, followed by magnetic trapping and ... More

Review on 'Integrability of the S-Matrix vs Integrability of the Hamiltonian' by C. Jung and T.H. SeligmanDec 16 1997We review the paper 'Integrability of the S-Matrix vs Integrability of the Hamiltonian' by C. Jung and T.H. Seligman (Phys. Rep. 285, 77-141 (1997)). This paper deals with the connection between the integrability of the scattering matrix $S$ and the integrability ... More

Quantum Transition from Order to Chaos in the Nuclear Shell ModelJul 21 1997We discuss the role of quantum chaos in atomic nuclei. After reviewing the basic assumptions of the nuclear shell model, we analyze the spectral statistics of the energy levels obtained with realistic shell-model calculations in the fp shell. In particular, ... More

On the Torus Quantization of Two Anyons with Coulomb Interaction in a Magnetic FieldApr 10 1997We study two anyons with Coulomb interaction in a uniform magnetic field $B$. By using the torus quantization we obtain the modified Landau and Zeeman formulas for the two anyons. Then we derive a simple algebraic equation for the full spectral problem ... More

Multi Solitons of a Bose-Einstein Condensate in a Three-Dimensional RingNov 03 2005A Bose-Einstein Condensate (BEC) made of alkali-metal atoms at ultra-low temperatures is well described by the three-dimensional cubic nonlinear Schr\"odinger equation, the so-called Gross-Pitaevskii equation (GPE). Here we consider an attractive BEC ... More

Particles and Anti-Particles in a Relativistic Bose CondensateJul 22 2002We study the Bose-Einstein condensation (BEC) for a relativistic ideal gas of bosons. In the framework of canonical thermal field theory, we analyze the role of particles and anti-particles in the determination of BEC transition temperature. At the BEC ... More

Embedding right-angled Artin groups into graph braid groupsJun 13 2005Apr 02 2010We construct an embedding of any right-angled Artin group $G(\Delta)$ defined by a graph $\Delta$ into a graph braid group. The number of strands required for the braid group is equal to the chromatic number of $\Delta$. This construction yields an example ... More

Time-dependent Hypercritical Accretion onto Black HolesDec 10 1996Results are presented from a time-dependent, numerical investigation of super-Eddington spherical accretion onto black holes with different initial conditions. We have studied the stability of stationary solutions, the non-linear evolution of shocked ... More

Detections of millisecond pulsars with the Fermi Large Area TelescopeOct 25 2009The Fermi observatory was launched on June 11, 2008. It hosts the \emph{Large Area Telescope} (LAT), sensitive to $\gamma$-ray photons from 20 MeV to over 300 GeV. When the LAT began its activity, nine young and energetic pulsars were known in $\gamma$ ... More

Comment on "Bell's Theorem without Inequalities and without Alignments"Sep 20 2004In this Comment we show that Cabello's proof of Bell's theorem without inequalities [Phys. Rev. Lett. 91, 230403 (2003)] does not exhibit two of the three "remarkable properties" which the proof is claimed to possess. More precisely it is our purpose ... More