Results for "Angelos Tsiaras"

total 1459took 0.11s
High-precision stellar limb-darkening in exoplanetary transitsApr 26 2017Aug 31 2017Characterization of the atmospheres of transiting exoplanets relies on accurate measurements of the extent of the optically thick area of the planet at multiple wavelengths with a precision $\lesssim$100 parts per million (ppm). Next-generation instruments ... More
Integrating light-curve and atmospheric modelling of transiting exoplanetsNov 12 2018Spectral retrieval techniques are currently our best tool to interpret the observed exoplanet atmospheric data. Said techniques retrieve the optimal atmospheric components and parameters by identifying the best fit to an observed transmission/emission ... More
Pushing the Limits of Exoplanet Discovery via Direct Imaging with Deep LearningApr 12 2019Further advances in exoplanet detection and characterisation require sampling a diverse population of extrasolar planets. One technique to detect these distant worlds is through the direct detection of their thermal emission. The so-called direct imaging ... More
Wayne - A Simulator for HST WFC3 IR Grism SpectroscopyNov 29 2015Aug 22 2017Wayne is an algorithm that simulates Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) grism spectroscopic frames including sources of noise and systematics. It can simulate both staring and spatial scan modes, and observations such as the transit ... More
Evidence for Atmospheric Cold-trap Processes in the Noninverted Emission Spectrum of Kepler-13Ab Using HST/WFC3Dec 19 2016Sep 13 2017We observed two eclipses of the Kepler-13A planetary system, on UT 2014 April 28 and UT 2014 October 13, in the near-infrared using Wide Field Camera 3 on the Hubble Space Telescope. By using the nearby binary stars Kepler-13BC as a reference, we were ... More
Some observations on compact indestructible spacesNov 15 2012Inspired by a recent work of Dias and Tall, we show that a compact indestructible space is sequentially compact. We also prove that a Lindelof Hausdorff indestructible space has the finite derived set property and a compact Hausdorff indestructible space ... More
The deformation theory of local complete intersectionsMar 06 1997Apr 12 1999This is an expository paper on the subject of the title. It assumes basic scheme theory, commutative and homological algebra.
Low-energy R-parity violating SUSY with horizontal flavor symmetriesSep 29 2013In this talk, I will present the general structure of RPV couplings when a Froggatt-Nielsen horizontal symmetry is responsible for the flavor structure of both the SM and the MSSM. For sub-TeV ({\it natural}) SUSY, lepton number must be an accidental ... More
A search for time-integrated CP violation in $D^{0} \rightarrow h^{-}h^{+}$ decaysOct 31 2012Nov 05 2012The LHCb Collaboration has recently observed evidence of CP violation in neutral D meson decays. CP violation in the charm sector is generically expected to be very small in the Standard Model, but can be enhanced in many models of new physics. In this ... More
Einstein, Levi-Civita, and Bianchi relationsFeb 27 2007About an essential suggestion to Einstein by Levi-Civita in 1915. Unicuique suum.
GW's towards fundamental principles of GRSep 04 2007The physical non-existence of gravitational waves (GW's) as a consequence of the non-existence in general relativity (GR) of physically privileged reference frames, and of the ``plasticity'' of relativistic notion of a coordinate system.
Stability and area law for rapidly mixing quantum dissipative systemsMar 24 2017In this thesis we study properties of open quantum dissipative evolutions of spin systems on lattices described by Lindblad generators, in a particular regime that we denote rapid mixing. We consider dissipative evolutions with a unique fixed point, and ... More
An application of the modular method and the symplectic argument to a Lebesgue-Nagell equationNov 25 2018In this paper, we study the generalized Lebesgue-Nagell equation \[ x^2+7^{2k+1}=y^n. \] This is the last case of equations of the form $x^2+q^{2k+1}=y^n$ with $k\geq0$ and $q>0$ where $\mathbb{Q}(\sqrt{-q})$ has class number one. Our proof is based on ... More
Local picture and level-set percolation of the Gaussian free field on a large discrete torusJul 19 2017Nov 29 2018For $d \geq 3$ we obtain an approximation of the zero-average Gaussian free field on the discrete $d$-dimensional torus of large side length $N$ by the Gaussian free field on $\mathbb Z^d$, valid in boxes of roughly side length $N - N^\delta$ with $\delta ... More
Space Time Defects as a Source of Curvature and TorsionOct 28 2004Space time is described as a continuum four-dimensional medium similar to ordinary elastic continua. Exploiting the analogy internal stress states are considered. The internal ''stress'' is originated by the presence of defects. The defects are described ... More
Testing General RelativityMar 03 2015This lecture will present a review of the past and present tests of the General Relativity theory. The essentials of the theory will be recalled and the measurable effects will be listed and analyzed. The main historical confirmations of General Relativity ... More
Relativistic space-time positioning: principles and strategiesDec 03 2012Starting from the description of space-time as a curved four-dimensional manifold, null Gaussian coordinates systems as appropriate for relativistic positioning will be discussed. Different approaches and strategies will be reviewed, implementing the ... More
New signatures and limits on R-parity violation from resonant squark productionJan 14 2016May 06 2016We discuss resonant squark production at the LHC via baryonic $R$-parity violating interactions. The cross section easily exceeds pair-production and a new set of signatures can be used to probe squarks, particularly stops. These include dijet resonances, ... More
Measuring the angle $γ$ from penguin decays at LHCbFeb 04 2011In this paper we present first LHCb results on charmless charged two- and three-body $B$ meson decays. In particular, using the first picobarn of integrated luminosity, LHCb observed the $B^{0}\rightarrow K^{+}\pi^{-}$ and $B^{+}\rightarrow K^{+}\pi^{+}\pi^{-}$ ... More
Can rotation curves reveal the opacity of spiral galaxies ?Jan 18 2005Long-slit optical spectra along the major axis of spiral galaxies constitute a main source of information concerning the kinematics of galaxies. In highly inclined spiral galaxies the long-slit spectrum is distorted by dust, which obscures the innermost ... More
Compact Tetraquark Interpretation of the XYZ StatesDec 14 2015The past decade witnessed the observation of several exotic charmonium-like resonances, some of which are manifestly non-qqbar mesons. We review one of the most popular interpretations of such states: the compact tetraquark in the constituent diquark-antidiquark ... More
Semiclassical description of D-branes in SL(2)/U(1) gauged WZW modelApr 02 2003May 22 2003In this note we examine some semiclassical features of D-branes in the SL(2)/U(1) gauged WZW model and determine the small fluctuation spectra for one class of branes. We compare our results with expectations from the CFT side.
A conditional likelihood is required to estimate the selection coefficient in ancient DNAJun 20 2016Jul 11 2016Time-series of allele frequencies are a useful and unique set of data to determine the strength of natural selection on the background of genetic drift. Technically, the selection coefficient is estimated by means of a likelihood function built under ... More
On the cohomology and the Chow ring of the classifying space of PGL_pMay 03 2005Jul 03 2005We investigate the integral cohomology ring and the Chow ring of the classifying space of the complex projective linear group PGL_p, when p is an odd prime. In particular, we determine its additive structure completely, and we reduce the problem of determing ... More
Einsteinian Manifolds and Gravitational WavesNov 24 2007The full relativity of the concepts of motion and rest, which is characteristic of the Einsteinian general relativity (GR), does not allow the generation of physical gravitational waves (GW's). -- The undulatory nature of a metric tensor is not an invariant ... More
Study of the ultrametric structure of Finite Dimensional Spin Glasses throught a constrained Monte Carlo dynamicsApr 07 1997We report a very detailed relation about the study, by a constrained Monte Carlo dynamic, of a 4D EA spin glass model (J=+/- 1). In particular we concentrate our attention on the behaviour of the system under different bounds imposed in order to optimize ... More
Natural, R-parity violating supersymmetry and horizontal flavor symmetriesMay 13 2013Aug 06 2013The absence so far of any supersymmetric signals at the LHC pushes towards a rethinking of the assumptions underlying the MSSM. Because the large missing $E_T$ searches are inadequate to detect a LSP decaying within the detector, R-parity violating supersymmetry ... More
Computing all elliptic curves over an arbitrary number field with prescribed primes of bad reductionNov 16 2015In this paper we study the problem of how to determine all elliptic curves defined over an arbitrary number field $K$ with good reduction outside a given finite set of primes $S$ of $K$ by solving $S$-unit equations. We give examples of elliptic curves ... More
The strained state cosmologyOct 03 2015Starting from some relevant facts concerning the behaviour of the universe over large scale and time span, the analogy between the geometric approach of General Relativ- ity and the classical description of an elastic strained material continuum is discussed. ... More
On the minimal compactification of a polynomial in two variablesApr 08 1999Aug 02 1999Consider a primitive polynomial $f$ in two variables, thought of as a map from the affine plane to the affine line. We study the minimimal compactification of $f$; from our result one deduces in particular that if one of the fibers of $f$ has only one ... More
The use of low temperature detectors for direct measurements of the mass of the electron neutrinoNov 03 2015Recent years have witnessed many exciting breakthroughs in neutrino physics. The detection of neutrino oscillations has proved that neutrinos are massive particles but the assessment of their absolute mass scale is still an outstanding challenge in today ... More
Coherent quantum transport in a star graphSep 04 2011A multi-branch quantum circuit is considered from the viewpoint of coherent electron or wave transport. Starting with the closed system, we give analytical conditions for the appearance of two isolated localized states out of the energy band. In the open ... More
Precise Propagation of Upper and Lower Probability Bounds in System PMar 07 2000In this paper we consider the inference rules of System P in the framework of coherent imprecise probabilistic assessments. Exploiting our algorithms, we propagate the lower and upper probability bounds associated with the conditional assertions of a ... More
A Cameron and Erdös conjecture on counting primitive setsNov 22 2017Let $f(n)$ count the number of subsets of $\{1,...,n\}$ without an element dividing another. In this paper I show that $f(n)$ grows like the $n$-th power of some real number, in the sense that $\lim_{n\rightarrow \infty}f(n)^{1/n}$ exists. This confirms ... More
On Gravitational MotionsApr 24 2008A new proof of the geodesic character of all motions of bodies that interact only gravitationally - and a detailed illustration of the real meaning of the linearized approximation of general relativity.
The Strained State CosmologySep 13 2011The chapter expounds a theory based on the interpretation of the dark energy as a strain energy of a physical continuum. The theory is based on the analogy that exists between the properties of space-time and the properties of elastic materials, when ... More
Is time enough in order to know where you are?Dec 25 2012This talk discusses various aspects of the structure of space-time presenting mechanisms leading to the explanation of the "rigidity" of the manifold and to the emergence of time, i.e. of the Lorentzian signature. The proposed ingredient is the analog, ... More
Using Stereoscopic 3D Technologies for the Diagnosis and Treatment of Amblyopia in ChildrenSep 28 2011The 3D4Amb project aims at developing a system based on the stereoscopic 3D techonlogy, like the NVIDIA 3D Vision, for the diagnosis and treatment of amblyopia in young children. It exploits the active shutter technology to provide binocular vision, i.e. ... More
Notes on Grothendieck topologies, fibered categories and descent theoryDec 28 2004May 24 2007This is an introduction to Grothendieck's descent theory, with some stress on the general machinery of fibered categories and stacks.
The revolution in physics of the early Nineteenth century revisited in the context of science-and-society interactionFeb 07 2018The radical changes in the concepts and approach in Physics at the turn of the Nineteenth century were so deep, that is acknowledged as a revolution. However, in 1970 Thomas Kuhn's careful reconstruction of the researches on the black body problem, the ... More
About the Notion of Truth in the Decoherent Histories Approach: a reply to GriffithsDec 13 1999Griffiths claims that the ``single family rule'', a basic postulate of the decoherent histories approach, rules out our requirement that any decoherent history has a unique truth value, independently from the decoherent family to which it may belong. ... More
Quasi Conjunction, Quasi Disjunction, T-norms and T-conorms: Probabilistic AspectsMar 20 2013We make a probabilistic analysis related to some inference rules which play an important role in nonmonotonic reasoning. In a coherence-based setting, we study the extensions of a probability assessment defined on $n$ conditional events to their quasi ... More
Pomerons and BCFW recursion relations for strings on D-branesSep 20 2010Dec 26 2010We derive pomeron vertex operators for bosonic strings and superstrings in the presence of D-branes. We demonstrate how they can be used in order to compute the Regge behavior of string amplitudes on D-branes and the amplitude of ultrarelativistic D-brane ... More
Network Coding-Based Cooperative ARQ SchemeJan 23 2012In this paper we introduce a novel Automatic Repeat reQuest (ARQ) scheme for cooperative wireless networks. Our scheme adopts network coding techniques in order to enhance the total bandwidth of the network by minimizing the total number of transmissions. ... More
Bounds on Collapse Models from Matter-Wave Interferometry: Calculational detailsJan 12 2016We present a simple derivation of the interference pattern in matter-wave interferometry as predicted by a class of master equations, by using the density matrix formalism. We apply the obtained formulae to the most relevant collapse models, namely the ... More
Free Energy of Multiple Overlapping ChainsNov 16 2011How accurate is pair additivity in describing interactions between soft polymer-based nanoparticles? Using numerical simulations we compute the free energy cost required to overlap multiple chains in the same region of space, and provide a quantitative ... More
Ride Sharing with a Vehicle of Unlimited CapacityJul 09 2015Jun 09 2016A ride sharing problem is considered where we are given a graph, whose edges are equipped with a travel cost, plus a set of objects, each associated with a transportation request given by a pair of origin and destination nodes. A vehicle travels through ... More
Frictionally decaying frontal warm-core eddiesJul 06 2016The dynamics of nonstationary, nonlinear, axisymmetric, warm-core geophysical surface frontal vortices affected by Rayleigh friction is investigated semi-analytically using the nonlinear, nonstationary reduced-gravity shallow-water equations. In this ... More
Precision Measurement of CP Violation in D0->pi+pi- at CDFNov 22 2010Dec 09 2010We report a preliminary measurement of the CP violating asymmetry in D0->pi+pi- using approximately 215,000 decays reconstructed in about 5.94/fb of CDF data. We use the strong D*+->D0pi+ decay ("D* tag") to identify the flavor of the charmed meson at ... More
Searching for New Physics through Charm at CDFMay 16 2011We report a search for non-Standard Model physics through the measurement of CP-violating asymmetry in the Cabibbo suppressed D0->pi+pi- and D0->K+K- decays reconstructed in about 5.94/fb of CDF data. We use the strong D*+->D0pi+ decay ("D* tag") to identify ... More
Parallel and Distributed Simulation: Five W's (and One H)May 02 2011May 03 2011A well known golden rule of journalism (and many other fields too) is that if you want to know the full story about something you have to answer all the five W's (Who, What, When, Where, Why) and the H (How). This extended abstract is about what is missing ... More
Non-Markovian quantum trajectories: an exact resultJul 09 2009Jul 30 2009We analyze the non-Markovian stochastic Schroedinger equation describing a particle subject to spontaneous collapses in space (in the language of collapse models), or subject to a continuous measurement of its position (in the language of continuous quantum ... More
Functional Lagrange formalism for time-non-local LagrangiansDec 12 2011Dec 21 2011We develop a time-non-local (TNL) formalism based on variational calculus, which allows for the analysis of TNL Lagrangians. We derive the generalized Euler-Lagrange equations starting from the Hamilton's principle and, by defining a generalized momentum, ... More
On the Electromagnetic Properties of Matter in Collapse ModelsAug 24 2009Nov 04 2009We discuss the electromagnetic properties of both a charged free particle, and a charged particle bounded by an harmonic potential, within collapse models. By choosing a particularly simple, yet physically relevant, collapse model, and under only the ... More
On weakening tightness to weak tightnessJan 15 2019The weak tightness $wt(X)$ of a space $X$ was introduced in [11] with the property $wt(X)\leq t(X)$. We investigate several well-known results concerning $t(X)$ and consider whether they extend to the weak tightness setting. First we give an example of ... More
Computer simulations of melts of randomly branching polymersOct 10 2016Randomly branching polymers with {\em annealed} connectivity are model systems for ring polymers and chromosomes. In this context, the branched structure represents transient folding induced by topological constraints. Here we present computer simulations ... More
The motivic class of the classifying stack of the special orthogonal groupSep 26 2016Jul 05 2017We compute the class of the classifying stack of the special orthogonal group in the Grothendieck ring of stacks, and check that it is equal to the multiplicative inverse of the class of the group.
Low-resolution measurements induced classicalitySep 26 2008The classical limit of quantum mechanics is discussed for closed quantum systems in terms of observational aspects. Initially, the failure of the limit h->0 is explicitly demonstrated in a model of two quantum mechanically interacting oscillators by showing ... More
Anti-correlation between multiplicity and orbital properties in exoplanetary systems as a possible record of their dynamical historiesAug 31 2017Previous works focused on exoplanets discovered with the radial velocity (RV) method reported an anti-correlation between the orbital eccentricities of the exoplanets and the multiplicity M (i.e., number of planets) of their system. We further investigate ... More
An Economic Bubble Model and Its First Passage TimeMar 21 2018We introduce a new diffusion process Xt to describe asset prices within an economic bubble cycle. The main feature of the process, which differs from existing models, is the drift term where a mean-reversion is taken based on an exponential decay of the ... More
Stacks of trigonal curvesMar 05 2009Apr 16 2010In this paper we give a presentation of the stack of trigonal curves as a quotient stack, and we compute its Picard group.
The Chow Ring of the Stack of Smooth Plane CubicsJun 20 2016Jan 14 2018We give an explicit presentation of the integral Chow ring of a stack of smooth plane cubics. We also determine some relations in the general case of hypersurfaces of any dimension and degree.
Higher algebraic K-theory for actions of diagonalizable groupsJul 24 2001Sep 17 2004We study the K-theory of actions of diagonalizable group schemes on noetherian regular separated algebraic spaces: our main result shows how to reconstruct the K-theory ring of such an action from the K-theory rings of the loci where the stabilizers have ... More
Fundamental gerbesOct 24 2016Jun 20 2017For a class of affine algebraic groups $\mathcal C$ over a field, we define the notions of $\mathcal C$-fundamental gerbe of a fibered category, generalizing what we had done in arXiv:1204.1260 for finite group schemes. We give sufficient conditions on ... More
The Nori fundamental gerbe of a fibered categoryApr 05 2012Dec 23 2012We give a condition that ensures that a fibered category over a field admits a universal morphism to a profinite gerbe. This fundamental gerbe generalizes both Nori's fundamental group scheme and Deligne's relative fundamental groupoid. Using a simplified ... More
On the irreducibility of secant cones, and an application to linear normalityNov 13 2001Let $Y \subset \P^r$ be a normal nondegenerate m-dimensional subvariety and let $\sigma(Y)$ denote the maximum dimension of a subvariety $Z \subset Y_{smooth}$ such that $Z$ contains a generic point of some divisor on $Y$ and the tangent planes $T_y Y$ ... More
Spontaneous photon-emission from a non-relativistic free charged particle in collapse models: A case-studyJul 01 2013Feb 10 2014We study the photon emission rate of a non relativistic charged particle interacting with an external classical noise through its position. Both the particle and the electromagnetic field are quantized. Under only the dipole approximation, the equations ... More
Fluid membranes can drive linear aggregation of adsorbed spherical nanoparticlesDec 29 2011Feb 06 2012Using computer simulations we show that lipid membranes can mediate linear aggregation of spherical nanoparticles binding to it for a wide range of biologically relevant bending rigidities. This result is in net contrast with the isotropic aggregation ... More
Massive gravitational waves from the Cosmic Defect theoryNov 17 2009The Cosmic Defect theory (CD), which is presented elsewhere in this conference, introduces in the standard Einstein-Hilbert Lagrangian an elastic term accounting for the strain of space-time viewed as a four-dimensional physical continuum. In this framework ... More
Charm Physics at CDFMay 22 2012The study of the charm quark continues to have wide interest as a possible avenue for the discovery of physics beyond the Standard Model and can as well be used as a tool for understanding the non-perturbative aspects of the strong interactions. Owning ... More
Schwarzschild manifold and non-regular coordinate transformations (A critico-historical Note)May 31 2009A careful analysis of the maximally extended metrics of Schwarzschild manifold shows that the original Schwarzschild's solution (1916) and Brillouin's solution (1923) are the only ones that are adequate from the physical standpoint. Contrary to the other ... More
Driving Currents for Flux Rope Coronal Mass EjectionsOct 23 2008We present a method for measuring electrical currents enclosed by flux rope structures that are ejected within solar coronal mass ejections (CMEs). Such currents are responsible for providing the Lorentz self-force that propels CMEs. Our estimates for ... More
A tensor theory of space-time as a strained material continuumMar 24 2009Nov 17 2009The classical theory of strain in material continua is reviewed and generalized to space-time. Strain is attributed to "external" (matter/energy fields) and intrinsic sources fixing the global symmetry of the universe (defects in the continuum). A Lagrangian ... More
On the relation between Schwarzschild's and Kerr's manifoldsMar 06 2009Kerr's manifold is only a Schwarzschild's manifold as seen by a suitably rotating coordinate system. By taking into account this fact, Kerr's manifold can be reduced to a Schwarzschild's manifold. In a final summary we give the main steps of our reasoning. ... More
A glimpse into the life and times of F.V.AtkinsonAug 24 2006We review the life and scientific work of F.V Atkinson, mathematician. The article consists of a brief overview of his academic and professional life followed by an extensive compilation of his life's work, some unpublished. He is best remembered for ... More
From the elasticity theory to cosmology and vice versaMay 24 2012The paper shows how a generalization of the elasticity theory to four dimensions and to space-time allows for a consistent description of the homogeneous and isotropic universe, including the accelerated expansion. The analogy is manifested by the inclusion ... More
Remarks on an 1828 theorem of ClausenJun 18 2008We list some explicit calculations related to a theorem of Clausen originally published in 1828, more commonly known as the result that describes the linear third order differential equation satisfied by the squares and the product of any two solutions ... More
Exact solution for a non-Markovian dissipative quantum dynamicsApr 19 2012We provide the exact analytic solution of the stochastic Schr\"odinger equation describing an harmonic oscillator interacting with a non-Markovian and dissipative environment. This result represents an arrival point in the study of non-Markovian dynamics ... More
The Simulation Model Partitioning Problem: an Adaptive Solution Based on Self-Clustering (Extended Version)Oct 05 2016Nov 04 2016This paper is about partitioning in parallel and distributed simulation. That means decomposing the simulation model into a numberof components and to properly allocate them on the execution units. An adaptive solution based on self-clustering, that considers ... More
On the long time behavior of Hilbert space diffusionNov 12 2008Stochastic differential equations in Hilbert space as random nonlinear modified Schroedinger equations have achieved great attention in recent years; of particular interest is the long time behavior of their solutions. In this note we discuss the long ... More
Coarse graining of master equations with fast and slow statesJan 23 2008Apr 20 2008We propose a general method for simplifying master equations by eliminating from the description rapidly evolving states. The physical recipe we impose is the suppression of these states and a renormalization of the rates of all the surviving states. ... More
Sensitivities and correlations of nuclear structure observables emerging from chiral interactionsJan 26 2016Aug 05 2016Starting from a set of different two- and three-nucleon interactions from chiral effective field theory, we use the importance-truncated no-core shell model for ab initio calculations of excitation energies as well as electric quadrupole (E2) and magnetic ... More
Parity and CT realization in QCDJan 17 1999Jul 19 1999We show that an essential assumption in the Vafa and Witten's theorem on P and CT realization in vector-like theories, the existence of a free energy density in Euclidean space in the presence of any external hermitian symmetry breaking source, does not ... More
Baryonic thermal fluctuations in finite temperature QCDOct 17 1998We show how, contrary to physical intuition, thermal fluctuations of physical states having a non-vanishing baryonic number can be fully neglected in the thermodynamics of QCD at any physical temperature. We also discuss on the consistency between our ... More
A general scheme for ensemble purificationJun 26 2002Nov 05 2002We exhibit a general procedure to purify any given ensemble by identifying an appropriate interaction between the physical system S of the ensemble and the reference system K. We show that the interaction can be chosen in such a way to lead to a spatial ... More
Probabilistic entailment in the setting of coherence: The role of quasi conjunction and inclusion relationJan 06 2013In this paper, by adopting a coherence-based probabilistic approach to default reasoning, we focus the study on the logical operation of quasi conjunction and the Goodman-Nguyen inclusion relation for conditional events. We recall that quasi conjunction ... More
Predict or classify: The deceptive role of time-locking in brain signal classificationMay 26 2016Jun 10 2016Several experimental studies claim to be able to predict the outcome of simple decisions from brain signals measured before subjects are aware of their decision. Often, these studies use multivariate pattern recognition methods with the underlying assumption ... More
Fundamental gerbesOct 24 2016For a class of affine algebraic groups $\mathcal C$ over a field, we define the notions of $\mathcal C$-fundamental gerbe of a fibered category, generalizing what we had done in arXiv:1204.1260 for finite group schemes. We give sufficient conditions on ... More
Fluctuation-Response Relation and modeling in systems with fast and slow dynamicsNov 07 2007We show how a general formulation of the Fluctuation-Response Relation is able to describe in detail the connection between response properties to external perturbations and spontaneous fluctuations in systems with fast and slow variables. The method ... More
A multi-protocol framework for the development of collaborative virtual environmentsDec 10 2014Mar 04 2015Collaborative virtual environments (CVEs) are used for collaboration and interaction of possibly many participants that may be spread over large distances. Both commercial and freely available CVEs exist today. Currently, CVEs are used already in a variety ... More
On the interpretative essence of the term "interaction-free measurement": The role of entanglementFeb 26 2008Dec 10 2008The polemical term "interaction-free measurement" (IFM) is analyzed in its interpretative nature. Two seminal works proposing the term are revisited and their underlying interpretations are assessed. The role played by nonlocal quantum correlations (entanglement) ... More
Approximate Variational Estimation for a Model of Network FormationFeb 01 2017Sep 20 2017We study an equilibrium model of sequential network formation with heterogeneous players. The payoffs depend on the number and composition of direct connections, but also the number of indirect links. We show that the network formation process is a potential ... More
Ring polymers in the melt state: the physics of crumplingOct 28 2013Sep 01 2014The conformational statistics of ring polymers in melts or dense solutions is strongly affected by their quenched microscopic topological state. The effect is particularly strong for non-concatenated unknotted rings, which are known to crumple and segregate ... More
Beyond Flory theory: Distribution functions for interacting lattice treesOct 17 2016While Flory theories provide an extremely useful framework for understanding the behavior of interacting, randomly branching polymers, the approach is inherently limited. Here we use a combination of scaling arguments and computer simulations to go beyond ... More
Conformational statistics of randomly-branching double-folded ring polymersAug 21 2018The conformations of topologically constrained double-folded ring polymers can be described as wrappings of randomly branched primitive trees. We extend previous work on the tree statistics under different (solvent) conditions to explore the conformational ... More
Spin equilibrium in strongly-magnetized accreting starsSep 27 2016Jun 15 2017Strongly magnetized accreting stars are often hypothesized to be in `spin equilibrium' with their surrounding accretion flows, which requires that the accretion rate changes more slowly than it takes the star to reach spin equilibrium. This is not true ... More
Quasi-Periodic Oscillations in magnetars: linking variability and emissionOct 24 2012I present recent results studying flare emission in magnetars. Strong quasi-periodic oscillations observed in the tail of giant magnetar flares are frequently interpreted as evidence for global seismic oscillations. I demonstrate that such a global oscillation ... More
Infinite games and cardinal properties of topological spacesDec 22 2012Feb 21 2013Inspired by work of Scheepers and Tall, we use properties defined by topological games to provide bounds for the cardinality of topological spaces. We obtain a partial answer to an old question of Bell, Ginsburg and Woods regarding the cardinality of ... More
Higher algebraic K-theory of group actions with finite stabilizersDec 19 1999May 22 2001We prove a decomposition theorem for the equivariant K-theory of actions of affine group schemes G of finite type over a field on regular separated noetherian algebraic spaces, under the hypothesis that the actions have finite geometric stabilizers and ... More
Infinite root stacks and quasi-coherent sheaves on logarithmic schemesOct 05 2014Dec 12 2017We define and study infinite root stacks of fine and saturated logarithmic schemes, a limit version of the root stacks introduced by Niels Borne and the second author. We show in particular that the infinite root stack determines the logarithmic structure, ... More