Search results for "deterministic"

showing 10 items of 141 documents

On the observability of Bell's inequality violation in the two-atoms optical Stern-Gerlach model

2005

Using the optical Stern-Gerlach model, we have recently shown that the non-local correlations between the internal variables of two atoms that successively interact with the field of an ideal cavity in proximity of a nodal region are affected by the atomic translational dynamics. As a consequence, there can be some difficulties in observing violation of the Bell's inequality for the atomic internal variables. These difficulties persist even if the atoms travel an antinodal region, except when the spatial wave packets are exactly centered in an antinodal point.

PhysicsMECHANICAL DESCRIPTIONTRANSLATIONAL DYNAMICSStern–Gerlach experimentIdeal (set theory)Field (physics)InequalityWave packetmedia_common.quotation_subjectDETERMINISTIC QUANTUM TELEPORTATIONCOMPLEMENTARITYAtomic and Molecular Physics and OpticsRABI OSCILLATIONSATOMSSCALAR PRODUCTHILBERT-SPACEQuantum mechanicsPhysics::Atomic and Molecular ClustersInternal variablePoint (geometry)Physics::Atomic PhysicsObservabilityPHYSICAL REALITYINTERFEROMETERmedia_common
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The Deterministic Annealing Filter: A new clustering method for gamma-ray tracking algorithms

2010

A new method of clustering for forward-tracking algorithms has been developed to reconstruct the tracks of gamma-rays in high-resolution detector systems such as AGATA (Advanced GAmma Tracking Array). This technique, called Deterministic Annealing Filter (DAF), comes from statistical physics and is used in high-energy physics. After a description of the DAF method and of the forward-tracking algorithm, the performance of this clustering method is discussed in terms of photopeak efficiency and peak-to-total ratio obtained with GEANT4 simulations for the AGATA geometry. A comparison with the standard so-called "cone clustering method" shows similar performances with a better photopeak efficie…

PhysicsNuclear and High Energy PhysicsGRETA010308 nuclear & particles physicsDetectorHigh multiplicityDeterministic annealingDeterministic annealing filter[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]Tracking (particle physics)01 natural sciencesGERMANIUMBACKTRACKINGgamma-ray spectroscopyFilter (video)0103 physical sciencesDETECTORSAGATAgamma-ray trackingSPECTROMETER010306 general physicsCluster analysisInstrumentationAlgorithm
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Teleportation of atomic states via position measurements

2007

We present a scheme for conditionally teleporting an unknown atomic state in cavity QED, which requires two atoms and one cavity mode. The translational degrees of freedom of the atoms are taken into account using the optical Stern-Gerlach model. We show that successful teleportation with probability 1/2 can be achieved through local measurements of the cavity photon number and atomic positions. Neither direct projection onto highly entangled states nor holonomous interaction-time constraints are required.

PhysicsTRANSLATIONAL DYNAMICSQuantum PhysicsPhotonDETERMINISTIC QUANTUM TELEPORTATIONDegrees of freedom (statistics)Cavity quantum electrodynamicsFOS: Physical sciencesPhysics::OpticsQuantum entanglementQuantum PhysicsQuantum energy teleportationTeleportationAtomic and Molecular Physics and OpticsProjection (linear algebra)PODOLSKY-ROSEN CHANNELSRABI OSCILLATIONSQuantum mechanicsPhysics::Atomic and Molecular ClustersJAYNES-CUMMINGS MODELPhysics::Atomic PhysicsAtomic physicsQuantum Physics (quant-ph)Quantum teleportation
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On the Size Complexity of Deterministic Frequency Automata

2013

Austinat, Diekert, Hertrampf, and Petersen [2] proved that every language L that is (m,n)-recognizable by a deterministic frequency automaton such that m > n/2 can be recognized by a deterministic finite automaton as well. First, the size of deterministic frequency automata and of deterministic finite automata recognizing the same language is compared. Then approximations of a language are considered, where a language L′ is called an approximation of a language L if L′ differs from L in only a finite number of strings. We prove that if a deterministic frequency automaton has k states and (m,n)-recognizes a language L, where m > n/2, then there is a language L′ approximating L such that L′ c…

Powerset constructionPushdown automatonComputer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing)Nonlinear Sciences::Cellular Automata and Lattice GasesCombinatoricsDeterministic pushdown automatonDeterministic finite automatonDeterministic automatonComputer Science::Programming LanguagesQuantum finite automataTwo-way deterministic finite automatonNondeterministic finite automatonComputer Science::Formal Languages and Automata TheoryMathematics
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Codes and automata

2006

Prefix codeTheoretical computer scienceFinite-state machineRegular languageComputer scienceDeterministic automatonAutomaton
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Properties and application of nondeterministic quantum query algorithms

2006

Many quantum algorithms can be analyzed in a query model to compute Boolean functions where input is given by a black box. As in the classical version of decision trees, different kinds of quantum query algorithms are possible: exact, zero-error, bounded-error and even nondeterministic. In this paper, we study the latter class of algorithms. We introduce a fresh notion in addition to already studied nondeterministic algorithms and introduce dual nondeterministic quantum query algorithms. We examine properties of such algorithms and prove relations with exact and nondeterministic quantum query algorithm complexity. As a result and as an example of the application of discovered properties, we…

Quantum PhysicsClass (set theory)Quantum queryComputer scienceDecision treeFOS: Physical sciencesDUAL (cognitive architecture)Nondeterministic algorithmBlack boxQuantum algorithmQuantum Physics (quant-ph)Boolean functionAlgorithmComputer Science::DatabasesSPIE Proceedings
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Influence of deterministic fluctuations on the 8-state Potts model

1999

We study a layered 8-state Potts model with an aperiodic modulation of the exchange couplings. Depending on its geometric properties, the aperiodic sequence may induce a 2nd order phase transition.

SequencePhase transitionHardware and ArchitectureAperiodic graphModulation (music)General Physics and AstronomyState (functional analysis)Statistical physicsMathematicsPotts modelDeterministic system
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Some Remarks on Automata Minimality

2011

It is well known that the minimization problem of deterministic finite automata (DFAs) is related to the indistinguishability notion of states (cf. [HMU00]). Indeed, a well known technique to minimize a DFA, essentially, consists in finding pairs of states that are equivalent (or indistinguishable), namely pairs of states (p,q) such that it is impossible to assert the difference between p and q only by starting in each of the two states and asking whether or not a given input string leads to a final state. Since, in the testing states equivalence, the notion of initial state is irrelevant, some of the main techniques for the minimization of automata, such as Moore’s algorithm [Moo56] and Ho…

Set (abstract data type)Discrete mathematicsDeterministic finite automatonSettore INF/01 - InformaticaRegular languageCayley graphString (computer science)state-pair graph uniformly minimal automataState (functional analysis)Equivalence (measure theory)Computer Science::Formal Languages and Automata TheoryAutomatonMathematics
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Internal Time and Innovation

2003

Consider a physical system that may be observed through time-varying quantities x t , where t stands for time that may be discrete or continuous. The set x t may be a realization of a deterministic system, e.g. a unique solution of a differential equation, or a stochastic process. In the latter case each x t is a random variable. We are interested in the global evolution of the system, not particular realizations x t , from the point of view of innovation. We call the evolution innovative if the dynamics of the system is such that there is a gain of information about the system as time increases. Our purpose is to associate the concept of internal time with such systems. The internal time w…

Set (abstract data type)Stochastic processComputer scienceDifferential equationPhysical systemApplied mathematicsPoint (geometry)Random variableRealization (probability)Deterministic system
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Rateless Codes Performance Analysis in Correlated Channel Model for GEO Free Space Optics Downlinks

2012

Settore ING-INF/03 - TelecomunicazioniFree Space Optics (FSO) technologies for satellite communications offer several advantages: wide bandwidth high rate capability immunity to electromagnetic interference and small equipment size. Thus they are suitable for inter-satellite links deep space communications and also for high data rate ground-to-satellite/satellite-to-ground communications. Nevertheless FSO links suffer impairments that cause power signal degradation at the receiver. Scattering and absorption cause power signal attenuations predictable by suitable deterministic models. Optical turbulence causes random irradiance fluctuations which can generate signal fading events and can thereby only be predicted by statistical models. Attenuation and fading events can corrupt FSO links and so it would be recommended to add mitigation error codes on the communication link. FSO channel can be described as an erasure channel: fading events can cause erasure errors. We have identified in rateless codes (RCs) a suitable solution to be employed in FSO links. RCs do not need feedback and they add a redundant coding on the source data that allows the receiver to recover the whole payload despite erasure errors. We implemented two different of rateless codes: Luby Transform (LT) and Raptor. We analyzed their performances on a simulated turbulent GEO FSO downlink (1 Gbps - OOK modulation) at a 106 μm wavelength and for different values of zenith angles. Assuming a plane-wave propagation and employing Hufnagel-Valley we modeled the downlink using: 1) a temporal correlated channel model based on Gamma-Gamma probability distribution and 2) an irradiance covariance function that we converted on a time function using Taylor frozen eddies hypothesis. Our new channel model is able to simulate irradiance fluctuations at different turbulence conditions as it will be shown in the full paper. We will also report performance results of LT and Raptor codes at overhead range varying between 0 and 50% and for different values of source packets.Settore ING-INF/01 - Elettronica
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