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Traversable Wormholes in Distorted GravityJun 11 2015We consider the effects of Distorted Gravity on the traversability of the wormholes. In particular, we consider configurations which are sustained by their own gravitational quantum fluctuations. The Ultra-Violet divergences appearing to one loop are ... More

The Cosmological Constant as an Eigenvalue of a Sturm-Liouville Problem and its RenormalizationOct 13 2005We discuss the case of massive gravitons and their relation with the cosmological constant, considered as an eigenvalue of a Sturm-Liouville problem. A variational approach with Gaussian trial wave functionals is used as a method to study such a problem. ... More

How Spacetime Foam modifies the brick wallSep 03 2004We re-examine the brick-wall model in the context of spacetime foam. In particular we consider a foam composed by wormholes of different sizes filling the black hole horizon. The contribution of such wormholes is computed via a scale invariant distribution. ... More

Spacetime Foam and Vacuum EnergyDec 03 2002A simple model of spacetime foam, made by spherically symmetric wormholes, with or without a cosmological term is proposed. The black hole area quantization and its consequences are examined in this context. We open the possibility of probing Lorentz ... More

Space Time Foam: a ground state candidate for Quantum GravityOct 16 2001A model of space-time foam, made by $N$ wormholes is considered. The Casimir energy leading to such a model is computed by means of the phase shift method which is in agreement with the variational approach used in Refs.[9-14]. The collection of Schwarzschild ... More

Modified Dispersion Relations and Black Hole EntropyFeb 23 2009Feb 09 2010We compute the black hole entropy in the context of the Modified Dispersion Relations using the brick wall model. An explicit dependence of the radial coordinate approaching the horizon is shown to analyze the behavior of the divergence. We find that, ... More

Casimir energy, the cosmological constant and massive gravitonsOct 13 2005The cosmological constant appearing in the Wheeler-De Witt equation is considered as an eigenvalue of the associated Sturm-Liouville problem. A variational approach with Gaussian trial wave functionals is used as a method to study such a problem. We approximate ... More

Casimir energy and variational methods in AdS spacetimeJun 21 2000Following the subtraction procedure for manifolds with boundaries, we calculate by variational methods, the Schwarzschild-Anti-de Sitter and the Anti-de Sitter space energy difference. By computing the one loop approximation for TT tensors we discover ... More

Probing Vacuum with Variational Methods in Quantum GravitySep 30 1998We use variational methods to calculate quasilocal energy quantum corrections. A comparison with the effective potential calculated at quadratic order is made by means of gaussian wave functionals. The method is a particular case of the effective action ... More

Naked Singularity in a Modified Gravity TheoryFeb 06 2009The cosmological constant induced by quantum fluctuation of the graviton on a given background is considered as a tool for building a spectrum of different geometries. In particular, we apply the method to the Schwarzschild background with positive and ... More

The induced Cosmological Constant as a tool for exploring geometriesDec 21 2008The cosmological constant induced by quantum fluctuation of the graviton on a given background is considered as a tool for building a spectrum of different geometries. In particular, we apply the method to the Schwarzschild background with positive and ... More

Self sustained traversable wormholes and the equation of stateJan 02 2007We compute the graviton one loop contribution to a classical energy in a \textit{traversable} wormhole background. The form of the shape function considered is obtained by the equation of state $p=\omega\rho$. We investigate the size of the wormhole as ... More

Vacuum Energy, Variational Methods and the Casimir EnergyJan 31 1999Following the subtraction procedure for manifolds with boundaries, we calculate by variational methods, the Schwarzschild and Flat space energy difference. The one loop approximation for TT tensors is considered here. An analogy between the computed energy ... More

Vacuum Energy Estimates in Quantum Gravity and the Wheeler-DeWitt EquationApr 01 1996In the Wheeler-DeWitt framework, by a gauge fixing procedure, we set up a scheme to recover a Schr\"odinger type equation, living in the orbits space with the {\it lapse} function as evolution parameter. By means of the associated stationary equation, ... More

Self Sustained Traversable Wormholes Induced by Gravity's Rainbow and Noncommutative GeometryDec 18 2012We compare the effects of Noncommutative Geometry and Gravity's Rainbow on traversable wormholes which are sustained by their own gravitational quantum fluctuations. Fixing the geometry on a well tested model, we find that the final result shows that ... More

Wormholes or Gravastars?Jan 21 2010The one loop effective action in a Schwarzschild background is here used to compute the Zero Point Energy (ZPE) which is compared to the same one generated by a gravastar. We find that only when we set up a difference between ZPE in these different background ... More

Black hole pair creation and the stability of flat spaceSep 16 2005We extend the Gross-Perry-Yaffe approach of hot flat space instability to Minkowski space. This is done by a saddle point approximation of the partition function in a Schwarzschild wormhole background which is coincident with an eternal black hole. The ... More

Self Sustained Traversable Wormholes?Jan 31 2005We compute the graviton one loop contribution to a classical energy in a traversable wormhole background. Such a contribution is evaluated by means of a variational approach with Gaussian trial wave functionals. A zeta function regularization is involved ... More

Can Reissner-Nordström wormholes be considered for Spacetime Foam formation?Feb 07 2002A simple model of spacetime foam, made by $N$ Reissner-Nordstr\"{o}m wormholes with a magnetic and electric charge in a semiclassical approximation, is taken under examination. The Casimir-like energy of the quantum fluctuation of such a model is computed ... More

A Spacetime Foam Approach to the Schwarzschild-de Sitter EntropyMar 22 2000The entropy for a black hole in a de Sitter space is approached within the framework of spacetime foam. A simple model, made by $N$ wormholes in a semiclassical approximation, is taken under examination to compute the entropy for such a case. An extension ... More

The Distorted Wheeler-DeWitt EquationDec 15 2015The Wheeler-DeWitt Equation represents a tool to study Quantum Gravity and Quantum Cosmology. Its solution in a very general context is, of course, impossible. To this purpose we consider some distortions of General Relativity like Gravity's Rainbow, ... More

Modified Dispersion Relations and Noncommutative Geometry lead to a finite Zero Point EnergyFeb 01 2011We compute Zero Point Energy in a spherically symmetric background with the help of the Wheeler-DeWitt equation. This last one is regarded as a Sturm-Liouville problem with the cosmological constant considered as the associated eigenvalue. The graviton ... More

Multigravity and Space Time FoamDec 06 2006We consider a multigravity approach to spacetime foam. As an application we give indications on the computation of the cosmological constant, considered as an eigenvalue of a Sturm-Liouville problem. A variational approach with Gaussian trial wave functionals ... More

A coherent approach to Spacetime FoamNov 23 2000A coherent superposition of N Schwarzschild wormholes is proposed as a model for spacetime foam. Following the subtraction procedure for manifolds with boundaries, we calculate by variational methods the Casimir energy. A proposal for an alternative foamy ... More

Spacetime Foam and the Casimir EnergyJun 04 1999Jun 06 2000We conjecture that the neutral black hole pair production is related to the vacuum fluctuation of pure gravity via the Casimir-like energy. A generalization of this process to a multi-black hole pair is considered. Implications on the foam-like structure ... More

Large N wormhole approach to spacetime foamNov 20 1998Nov 26 1998A simple model of spacetime foam, made by $N$ wormholes in a semiclassical approximation, is taken under examination. We show that the qualitative behaviour of the fluctuation of the metric conjectured by Wheeler is here reproduced.

Space-time Foam, Casimir energy and black hole pair creationJan 14 1998We conjecture that the neutral black hole pair production is related to the vacuum fluctuation of pure gravity via the Casimir-like energy. Implications on the foam-like structure of spacetime are discussed.

Wormholes and Black Hole Pair CreationAug 31 1996We analyze the possibility of black holes pair creation induced by three dimensional wormholes. Although this spacetime configuration is nowadays hard to suppose, it can be very important in the early universe, when the wormhole spacetime foam representation ... More

Effects of Modified Dispersion Relations and Noncommutative Geometry on the Cosmological Constant ComputationDec 18 2012We compute Zero Point Energy in a spherically symmetric background with the help of the Wheeler-DeWitt equation. This last one is regarded as a Sturm-Liouville problem with the cosmological constant considered as the associated eigenvalue. The graviton ... More

Extracting the Cosmological Constant from the Wheeler DeWitt Equation in a Modified Gravity TheoryDec 19 2007We discuss how to extract information about the cosmological constant from the Wheeler-DeWitt equation, considered as an eigenvalue of a Sturm-Liouville problem. A generalization to a f(R)theory is taken under examination. The equation is approximated ... More

Entropy from the foam IINov 21 2001Jun 04 2002A simple model of spacetime foam, made by two different types of wormholes in a semiclassical approximation, is taken under examination: one type is a collection of $N_{w}$ Schwarzschild wormholes, while the other one is made by Schwarzschild-Anti-de ... More

Casimir Energy and the Cosmological ConstantSep 03 2004We regard the Wheeler-De Witt equation as a Sturm-Liouville problem with the cosmological constant considered as the associated eigenvalue. The used method to study such a problem is a variational approach with Gaussian trial wave functionals. We approximate ... More

Entropy and the cosmological constant: a spacetime-foam approachOct 11 1999Oct 12 1999A simple model of spacetime foam, made by N wormholes in a semiclassical approximation, is taken under examination. The Casimir-like energy of the quantum fluctuation of such a model and its probability of being realized are computed. Implications on ... More

Energy Computation in Wormhole Background with the Wheeler-DeWitt OperatorsJan 09 1997We investigate the possibility of computing energy by means of operators associated to the Wheeler-DeWitt equation. By choosing three dimensional wormholes as a framework, we apply such calculation scheme to the black hole pair creation. We compare our ... More

The Cosmological Constant in Distorted Quantum CosmologyMar 12 2015We give a calculation scheme for the cosmological constant computation with the help of the Wheeler-DeWitt equation. This last one is regarded as a Sturm-Liouville problem with the cosmological constant considered as the associated eigenvalue. By fixing ... More

Distorting General Relativity: Gravity's Rainbow and f(R) theories at workOct 29 2012Jun 13 2013We compute the Zero Point Energy in a spherically symmetric background combining the high energy distortion of Gravity's Rainbow with the modification induced by a f(R) theory. Here f(R) is a generic analytic function of the Ricci curvature scalar R in ... More

Gravitational Zero Point Energy and the Induced Cosmological ConstantJul 29 2010We discuss how to extract information about the cosmological constant from the Wheeler-DeWitt equation, considered as an eigenvalue of a Sturm-Liouville problem in a generic spherically symmetric background. The equation is approximated to one loop with ... More

Extracting the Maxwell charge from the Wheeler-DeWitt equationJul 01 2008We consider the Wheeler-De Witt equation as a device for finding eigenvalues of a Sturm-Liouville problem. In particular, we will focus our attention on the electric (magnetic) Maxwell charge. In this context, we interpret the Maxwell charge as an eigenvalue ... More

On the existence of nontrivial solutions for a nonlinear equation relative to a measure-valued Lagrangian on homogeneous spacesOct 11 2000We prove the existence of a non-trivial solution for a nonlinear equation related to a measure-valued Lagrangian. The result is based on a compact embedding theorem of the Lagrangian domain and on the application of the Mountain Pass Theorem joined to ... More

A Spacetime Foam approach to the cosmological constant and entropyMar 22 2000Jun 04 2002A simple model of spacetime foam, made by $N$ wormholes in a semiclassical approximation, is taken under examination. The Casimir-like energy of the quantum fluctuation of such a model and its probability of being realized are computed. Implications on ... More

Vacuum Energy in Ultralocal metrics for TT tensors with Gaussian Wave FunctionalsAug 29 1995Apr 21 1996We calculate, in a class of Gauge invariant functionals, by variational methods, the difference of vacuum energy between two different backgrounds: Schwarzschild and Flat Space. We perform this evaluation in an Hamiltonian formulation of Quantum Gravity ... More

Modified Dispersion Relations: from Black-Hole Entropy to the Cosmological ConstantDec 07 2011Quantum Field Theory is plagued by divergences in the attempt to calculate physical quantities. Standard techniques of regularization and renormalization are used to keep under control such a problem. In this paper we would like to use a different scheme ... More

The Cosmological constant and the Wheeler-DeWitt EquationOct 09 2009Oct 22 2009We discuss how to extract information about the cosmological constant from the Wheeler-DeWitt equation, considered as an eigenvalue of a Sturm-Liouville problem. The equation is approximated to one loop with the help of a variational approach with Gaussian ... More

What Casimir Energy can suggest about Space Time Foam?Oct 20 2001In the context of a model of space-time foam, made by $N$ wormholes we discuss the possibility of having a foam formed by different configurations. An equivalence between Schwarzschild and Schwarzschild-Anti-de Sitter wormholes in terms of Casimir energy ... More

Casimir energy and black hole pair creation in Schwarzschild-de Sitter spacetimeDec 20 2000Jan 22 2001Following the subtraction procedure for manifolds with boundaries, we calculate by variational methods, the Schwarzschild-de Sitter and the de Sitter space energy difference. By computing the one loop approximation for TT tensors we discover the existence ... More

Wormholes and Spacetime Foam: an approach to the Cosmological Constant and EntropyNov 14 2000This paper summarizes the contribution presented at the IX Marcel Grossmann Meeting (Rome, July 2000). A simple model of spacetime foam, made by $N$ Schwarzschild wormholes in a semiclassical approximation, is here proposed. The Casimir-like energy of ... More

Entropy from the foamJun 09 1999A simple model of spacetime foam, made by N wormholes in a semiclassical approximation, is taken under examination. We show that the Bekenstein-Hawking entropy is here ``quantized'' in agreement with the heuristic calculation of Bekenstein.

Green's Functions and Energy Decay on Homogeneous SpacesAug 09 1997Nov 22 2000We consider a homogeneous space X=(X,d,m) of dimension $\nu \geq 1$ and a local regular Dirichlet form in L^{2}(X,m). We prove that if a Poincar\'{e} inequality holds on every pseudo-ball B(x,R) of X, with local characteristic constant c_{0}(x) and c_{1}(r), ... More

Self Sustained Traversable Wormholes and Topology Change Induced by Gravity's RainbowNov 13 2013We consider the effects of Gravity's Rainbow on the self-sustained equation which is responsible to find new traversable wormholes configurations which are sustained by their own gravitational quantum fluctuations. The same self-sustained equation is ... More

Gravitational Zero Point Energy induces Physical ObservablesFeb 12 2010We consider the contribution of Zero Point Energy on the induced Cosmological Constant and on the induced Electric/Magnetic charge in absence of matter fields. The method is applicable to every spherically symmetric background. Extensions to a generic ... More

The cosmological constant as an eigenvalue of the Hamiltonian constraint in Horava-Lifshits theoryDec 01 2009Dec 03 2012In the framework of Horava-Lifshitz theory, we study the eigenvalues associated with the Wheeler-DeWitt equation representing the vacuum expectation values associated with the cosmological constant. The explicit calculation is performed with the help ... More

Running Cosmological Constant and Running Newton Constant in Modified Gravity TheoriesNov 12 2009We discuss how to extract information about the cosmological constant from the Wheeler-DeWitt equation, considered as an eigenvalue of a Sturm-Liouville problem in a de Sitter and Anti-de Sitter background. The equation is approximated to one loop with ... More

Probing foamy spacetime with Variational MethodsMay 27 1998A one-loop correction of the quasilocal energy in the Schwarzschild background, with flat space as a reference metric, is performed by means of a variational procedure in the Hamiltonian framework. We examine the graviton sector in momentum space, in ... More

Harnack Inequality on Homogeneous SpacesApr 03 1996Aug 03 2000We consider a homogeneous space $X=(X,d,m) $ of dimension $\nu\geq1$ and a local regular Dirichlet form in $L^{2}(X,m) .$ We prove that if a Poincar\'{e} inequality holds on every pseudo-ball $B(x,R) $ of $X$, then an Harnack's inequality can be proved ... More

Results on Multiple Coulomb Scattering from 12 and 20 GeV electrons on Carbon targetsMay 28 2019Multiple scattering effects of 12 and 20 GeV electrons on 8 and 20 mm thickness carbon targets have been studied with high-resolution silicon microstrip detectors of the UA9 apparatus at the H8 line at CERN. Comparison of the scattering angle between ... More

Cosmological Constant from a Deformation of the Wheeler-DeWitt EquationOct 15 2015Feb 23 2016In this paper, we consider the Wheeler-DeWitt equation modified by a deformation of the second quantized canonical commutation relations. Such modified commutation relations are induced by a Generalized Uncertainty Principle. Since the Wheeler-DeWitt ... More

Particle propagation and effective space-time in Gravity's RainbowSep 29 2011Basing on the results obtained in a our previous study on Gravity's Rainbow, we determine the quantum corrections to the space-time metric for the Schwarzschild and the de Sitter background, respectively. We analyze how quantum fluctuations alter these ... More

Gravity's Rainbow and Compact StarsDec 29 2015A number of recent studies has focused on the implications of new physics at the Planck scale on the equilibrium of compact astrophysical objects such as white dwarf and neutron stars. Here we analyze the modification of the equilibrium configurations ... More

Finite Zero Point Gravitational Energy in the context of Modified Dispersion RelationsJan 02 2013We compute the Zero Point Energy in a spherically symmetric background distorted at high energy as predicted by Gravity's Rainbow. In this context we setup a Sturm-Liouville problem with the cosmological constant considered as the associated eigenvalue. ... More

Modified Dispersion Relations lead to a finite Zero Point Gravitational EnergyFeb 18 2011We compute the Zero Point Energy in a spherically symmetric background distorted at high energy as predicted by \textit{Gravity's Rainbow}. In this context we setup a Sturm-Liouville problem with the cosmological constant considered as the associated ... More

Does Gravity's Rainbow induce Inflation without an Inflaton?Dec 20 2012Aug 20 2014We study aspects of quantum cosmology in the presence of a modified space-time geometry. In particular, within the context of Gravity's Rainbow modified geometry, motivated from quantum gravity corrections at the Planck energy scale, we show that the ... More

Naked Singularities are not Singular in Distorted GravityNov 07 2013Aug 20 2014We compute the Zero Point Energy (ZPE) induced by a naked singularity with the help of a reformulation of the Wheeler-DeWitt equation. A variational approach is used for the calculation with Gaussian Trial Wave Functionals. The one loop contribution of ... More

The cosmological constant as an eigenvalue of f(R)-gravity Hamiltonian constraintFeb 14 2007In the framework of ADM formalism, it is possible to find out eigenvalues of the WDW equation with the meaning of vacuum states, i.e. cosmological constants, for f(R) theories of gravity, where f(R) is a generic analytic function of the Ricci curvature ... More

Electric Charges and Magnetic Monopoles in Gravity's RainbowMay 15 2013Aug 20 2014In this work, we explore the possibility that quantum fluctuations induce an electric or magnetic charge or both, in the context of Gravity's Rainbow. A semi-classical approach is adopted, where the graviton one-loop contribution to a classical energy ... More

A noncommutative approach to the cosmological constant problemJun 28 2010Mar 15 2011In this paper we study the cosmological constant emerging from the Wheeler-DeWitt equation as an eigenvalue of the related Sturm-Liouville problem. We employ Gaussian trial functionals and we perform a mode decomposition to extract the transverse-traceless ... More

Rainbow's StarsJul 27 2016In recent years, a growing interest on the equilibrium of compact astrophysical objects like white dwarf and neutron stars has been manifested. In particular, various modifications due to Planck scale energy effects have been considered. In this paper ... More

The Cosmological Constant as an Eigenvalue of the Hamiltonian constraint in a Varying Speed of Light theoryMar 12 2015In the framework of a Varying Speed of Light theory, we study the eigenvalues associated with the Wheeler-DeWitt equation representing the vacuum expectation values associated with the cosmological constant. We find that the Wheeler-DeWitt equation for ... More

Gravity's Rainbow: a bridge towards Horava-Lifshitz gravityNov 25 2014We investigate the connection between Gravity's Rainbow and Horava-Lifshitz gravity, since both theories incorporate a modification in the UltraViolet regime which improves their quantum behavior at the cost of the Lorentz invariance loss. In particular, ... More

Point-like sources and the scale of quantum gravityApr 22 2009We review the General Relativistic model of a (quasi) point-like particle represented by a massive shell of neutral matter which has vanishing total energy in the small-volume limit. We then show that, by assuming a Generalised Uncertainty Principle, ... More

Self-sustained traversable wormholes in noncommutative geometryNov 06 2008Dec 04 2008In this work, we find exact wormhole solutions in the context of noncommutative geometry, and further explore their physical properties and characteristics. The energy density of these wormhole geometries is a smeared and particle-like gravitational source, ... More

Gravity's Rainbow induces Topology ChangeMar 22 2013Aug 20 2014In this work, we explore the possibility that quantum fluctuations induce a topology change, in the context of Gravity's Rainbow. A semi-classical approach is adopted, where the graviton one-loop contribution to a classical energy in a background spacetime ... More

Self sustained phantom wormholes in semi-classical gravityJan 02 2007Jun 28 2007A possible candidate for the late time accelerated expanding Universe is phantom energy, which possesses rather bizarre properties, such as the prediction of a Big Rip singularity and the violation of the null energy condition. The latter is a fundamental ... More

Self-sustained traversable wormholes in modified gravity theoriesJan 02 2013We consider the possibility that wormhole geometries are sustained by their own quantum fluctuations, in the context of noncommutative geometry and Gravity's Rainbow models. More specifically, the energy density of the graviton one-loop contribution to ... More

Self-sustained wormholes in modified dispersion relationsNov 24 2011In this work, we consider the possibility that wormhole geometries are sustained by their own quantum fluctuations, in the context of modified dispersion relations. More specifically, the energy density of the graviton one-loop contribution to a classical ... More

Gravity's Rainbow and Traversable WormholesNov 25 2015In the context of Gravity's Rainbow, we compute the graviton one-loop contribution to a classical energy in a traversable wormhole background, by considering the equation of state $p_{r} = \omega\rho$. The investigation is evaluated by means of a variational ... More

Linearized stability analysis of gravastars in noncommutative geometryApr 14 2010In this work, we find exact gravastar solutions in the context of noncommutative geometry, and explore their physical properties and characteristics. The energy density of these geometries is a smeared and particle-like gravitational source, where the ... More

Commissioning and operation of the Cherenkov detector for proton Flux Measurement of the UA9 ExperimentApr 12 2019The UA9 Experiment at CERN-SPS investigates channeling processes in bent silicon crystals with the aim to manipulate hadron beams. Monitoring and characterization of channeled beams in the high energy accelerators environment ideally requires in-vacuum ... More

Phantom stars and topology changeAug 06 2008Nov 06 2008In this work, we consider time-dependent dark energy star models, with an evolving parameter $\omega$ crossing the phantom divide, $\omega=-1$. Once in the phantom regime, the null energy condition is violated, which physically implies that the negative ... More

Production and Decay of Scalar Stoponium Bound StatesDec 02 1993In this paper we discuss possible signatures for the production of scalar \stst\ (stoponium) bound states \sigst\ at hadron colliders, where \st\ is the lighter scalar top eigenstate. We first study the decay of \sigst; explicit expressions are given ... More

Parton Model in Lorentz Invariant Non-Commutative SpaceMay 26 2004Aug 22 2004We consider the Lorentz invariant non-commutative QED and complete the Feynman rules for the theory up to the order $\theta^2$. In the Lorentz invariant version of the non-commutative QED the particles with fractional charges can be also considered. We ... More

Electromagnetic Response of Weyl SemimetalsMar 22 2013Jun 27 2013It has been suggested recently, based on subtle field-theoretical considerations, that the electromagnetic response of Weyl semimetals and the closely related Weyl insulators can be characterized by an axion term E.B with space and time dependent axion ... More

The Charm Quark Contribution to the Proton Structure FunctionOct 14 2006Dec 27 2006The charm quark structure function $F^c_2$ and the longitudinal structure function $F_l^p$ are directly sensitive to the gluon content of proton and therefore are crucial in understanding of proton structure function, in particular at low momentum transfer ... More

The decay of singlet scalar dark matter to unparticle and photonMay 06 2008We consider the unparticle physics introduced by Georgi and show that if the standard model is extended to include a singlet scalar as a dark matter candidate, there is a channel which leads to its decay to photon and unparticle. We calculate the decay ... More

Quantum information processing: The case of vanishing interaction energyOct 27 2002We investigate the rate of operation of quantum "black boxes" ("oracles") and point out the possibility of performing an operation by a quantum "oracle" whose average energy equals zero. This counterintuitive result not only presents a generalization ... More

Self-Organized Topological State with Majorana FermionsJul 08 2013Nov 06 2013Topological phases, quite generally, are difficult to come by. They either occur under rather extreme conditions (e.g. the quantum Hall liquids, which require high sample purity, strong magnetic fields and low temperatures) or demand fine tuning of system ... More

Spin Response of Electrons on the Surface of a Topological InsulatorJan 11 2012The surface of a topological insulator hosts a very special form of a quasi-two dimensional metallic system when it is embedded in a topologically trivial medium like the vacuum. The electronic properties of this unusual 2D metal are distinct in many ... More

On the effect of the thermal gas component to the stability of vortices in trapped Bose-Einstein condensatesMar 12 2002We study the stability of vortices in trapped single-component Bose-Einstein condensates within self-consistent mean-field theories--especially we consider the Hartree-Fock-Bogoliubov-Popov theory and its recently proposed gapless extensions. It is shown ... More

Lorentz Conserving Noncommutative Standard ModelMar 29 2007May 10 2007We consider Lorentz conserving noncommutative field theory to construct the Lorentz conserving noncommutative standard model based on the gauge group $SU(3)\times SU(2)\times U(1)$. We obtain the enveloping algebra-valued of Higgs field up to the second ... More

Shelving and Probe Efficiency in Trapped Ion ExperimentsFeb 24 2014A generalized probe sequence typical of trapped ion experiments using shelving is studied. Detection efficiency is analyzed for finite shelved state lifetimes and using multi-modal count distributions. Multi-modal distributions are more appropriate for ... More

The Neutralino Relic Density in Minimal N=1 SupergravityJul 10 1992We compute the cosmic relic (dark matter) density of the lightest supersymmetric particle (LSP) in the framework of minimal $N=1$ Supergravity models with radiative breaking of the electroweak gauge symmetry. To this end, we re--calculate the cross sections ... More

Quantization and $2π$ Periodicity of the Axion Action in Topological InsulatorsJun 17 2010Nov 10 2010The Lagrangian describing the bulk electromagnetic response of a three-dimensional strong topological insulator contains a topological `axion' term of the form '\theta E dot B'. It is often stated (without proof) that the corresponding action is quantized ... More

A new signal for scalar top bound state productionOct 01 1993We study the production and decay of a scalar \stst\ bound state \sigst\ at hadron supercolliders, where \st\ is the lighter stop eigenstate. If \st\ has no tree--level 2--body decays, the dominant decay modes of \sigst\ are $gg$ or, if $m_h < \mst \ll ... More

Massive Neutrino in Non-commutative Space-timeDec 24 2007Apr 01 2008We consider the noncommutative standard model based on $SU(3)\times SU(2)\times U(1)$. We study the gauge transformation of right handed neutrino and its direct interaction with photon in the noncommutative space-time. We show that the massive Dirac neutrinos, ... More

Infinite order excitonic Bloch equations for asymmetric nanostructuresJul 04 2003We present a new exciton-based formalism for calculating the coherent response of asymmetric semiconductor multiple quantum well structures to ultra-short optical pulses valid to infinite order in the optical field and including the self-generated intraband ... More

Scalar StoponiumAug 18 1993We study the decays of a scalar \stst\ bound state \sigst, where \st\ is the lighter stop eigenstate. If \st\ has no tree--level 2--body decays, the dominant decay modes of \sigst\ are $gg$ or, if $m_h < \mst \ll \mstt$, a pair of light scalar Higgs bosons ... More

Photon Neutrino Scattering in Non-Commutative SpaceNov 04 2005Jan 19 2006We extend the non-commutative standard model based on the minimal $SU(3)\times SU(2)\times U(1)$ gauge group to include the interaction of photon with neutrino. We show that, in the gauge invariant manner, only the right handed neutrino can directly couple ... More

Complete Resolution of the Quantum Zeno Paradox for Outside ObserversJan 27 2004The quantum Zeno paradox is fully resolved for purely indirect and incomplete measurements performed by the detectors outside the system. If the outside detectors are prepared to observe propagating signals of a decay event of an excited state in the ... More

The relativistic nuclear dynamics for the SU(3) Goldstone bosons of chiral QCDDec 04 2002In this habilitation theses the chiral SU(3) Lagrangian is applied to antikaon and hyperon propagation in cold nuclear matter. The self consistent many-body dynamics relies on a detailed analysis of the pion, kaon and antikaon-nucleon scattering data ... More

Migdal's short range correlations in a covariant modelOct 26 2002Aug 13 2003We construct a covariant model for short range correlations of a pion emerged in nuclear matter. Once the delta-hole contribution is considered an additional and so far neglected channel opens that leads to significant modifications in the vicinity of ... More

Resolution of Verb Ellipsis in Japanese Sentence using Surface Expressions and ExamplesDec 13 1999Verbs are sometimes omitted in Japanese sentences. It is necessary to recover omitted verbs for purposes of language understanding, machine translation, and conversational processing. This paper describes a practical way to recover omitted verbs by using ... More