Results for "Ka Ho Yuen"

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Tracing 3D distribution of magnetic fields with gradients of synchrotron polarizationJan 31 2018In this paper, we describe a new technique for probing galactic and extragalactic 2D and 3D distribution of magnetic field using synchrotron polarization. Fluctuations of magnetic field are elongated along the ambient magnetic field directions. As a result, ... More
Diagnostics of turbulence properties through Velocity Gradient Amplitudes: Theory and ObservationsJan 31 2018Based on the properties of magneto-hydrodynamic (MHD) turbulence, the recent development of the Velocity Gradient Technique (VGT) allows observers to trace magnetic field directions using spectroscopic information. In this paper, we explore how the amplitudes ... More
Dispersion of velocity gradients: Mapping magnetization with the Velocity Gradient TechniqueFeb 08 2018Recent developments of the Velocity Gradient Technique (VGT) show that the velocity provides a robust measure of magnetic field direction. In this paper, we use velocity centroids as the measures of velocity and propose a new way of studying media magnetization. ... More
Tilings of the Sphere by Geometrically Congruent Pentagons IOct 08 2013May 08 2014We show that there are no edge-to-edge tilings of the sphere by congruent pentagons beyond the minimal dodecahedron tiling, such that there is a tile with all vertices having degree 3 and the edge length combinations are three of the five possibilities. ... More
Wireless Energy Beamforming using Received Signal Strength Indicator FeedbackApr 04 2017Dec 01 2017Multiple antenna techniques that allow energy beamforming have been looked upon as a possible candidate for increasing the transfer efficiency between the energy transmitter (ET) and the energy receiver (ER) in wireless power transfer. This paper introduces ... More
Beamforming Matrix Quantization with Variable Feedback RateJun 20 2008We propose an improved beamforming matrix compression by Givens Rotation with the use of variable feedback rate. The variable feedback rate means that the number of bits used to represent the quantized beamforming matrix is based on the value of the matrix. ... More
Winning in Sequential Parrondo Games by Players with Short-Term MemoryOct 19 2015Jan 10 2016The original Parrondo game, denoted as AB3, contains two independent games: A and B. The winning or losing of A and B game is defined by the change of one unit of capital. Game A is a losing game if played continuously, with winning probability $p=0.5-\epsilon$, ... More
Erratum: "Determining neutron star masses and radii using energy-resolved waveforms of X-ray burst oscillations" (ApJ, 776, 19 [2013])Jan 22 2018This erratum addresses an error in the text of Lo et al. (2013) and more importantly corrects a computational error that was made in all previously published relativistic computations of absolute pulse waveform fluxes produced by hot spots on rotating ... More
Exact Results for the Kepler Problem in General RelativityJul 25 2008Jul 27 2008Exact results are derived, specifically the perihelion shift and the Kepler orbit, for a bound test particle in the Schwarzschild metric with cosmological constant $\Lambda=0$. A series expansion, of $\Delta\phi = 2(2(1-2M/p(3-e))^{-1/2} K((4eM/p)/(1-2M/p(3-e)))-\pi)$, ... More
Self-Similar Solutions with Elliptic Symmetry for the Compressible Euler and Navier-Stokes Equations in R^{N}Apr 19 2011Based on Makino's solutions with radially symmetry, we extend the corresponding ones with elliptic symmetry for the compressible Euler and Navier-Stokes equations in R^{N} (N\geq2). By the separation method, we reduce the Euler and Navier-Stokes equations ... More
Blowup for $C^{2}$ Solutions of the N-dimensional Euler-Poisson Equations in Newtonian CosmologyMar 25 2014Pressureless Euler-Poisson equations with attractive forces are standard models in Newtonian cosmology. In this article, we further develop the spectral dynamics method and apply a novel spectral-dynamics-integration method to study the blowup conditions ... More
Blowup for the Euler and Euler-Poisson Equations with Repulsive ForcesJan 03 2010Oct 05 2010In this paper, we study the blowup of the $N$-dim Euler or Euler-Poisson equations with repulsive forces, in radial symmetry. We provide a novel integration method to show that the non-trivial classical solutions $(\rho,V)$, with compact support in $[0,R]$, ... More
A parallel repetition theorem for all entangled gamesApr 15 2016The behavior of games repeated in parallel, when played with quantumly entangled players, has received much attention in recent years. Quantum analogues of Raz's classical parallel repetition theorem have been proved for many special classes of games. ... More
A quantum lower bound for distinguishing random functions from random permutationsOct 10 2013Dec 20 2013The problem of distinguishing between a random function and a random permutation on a domain of size $N$ is important in theoretical cryptography, where the security of many primitives depend on the problem's hardness. We study the quantum query complexity ... More
Some Exact Blowup Solutions to the Pressureless Euler Equations in R^NOct 07 2009The pressureless Euler equations can be used as simple models of cosmology or plasma physics. In this paper, we construct the exact solutions in non-radial symmetry to the pressureless Euler equations in $R^{N}:$% [c]{c}% \rho(t,\vec{x})=\frac{f(\frac{1}{a(t)^{s}}\underset{i=1}{\overset ... More
Analytical Blowup Solutions to the 2-dimensional Isothermal Euler-Poisson Equations of Gaseous Stars IIMay 31 2009Jul 29 2009This article is the continued version of the analytical blowup solutions for 2-dimensional Euler-Poisson equations \cite{Y1}. With extension of the blowup solutions with radial symmetry for the isothermal Euler-Poisson equations in $R^{2}$, other special ... More
Analytical Blowup Solutions to the 3-dimensional Pressureless Navier-Stokes-Poisson Equations with Density-dependent ViscosityNov 03 2008We study the pressureless Navier--Stokes-Poisson equations of describing the evolution of the gaseous star in astrophysics. The isothermal blowup solutions of Yuen, to the Euler-Poisson equations in R2, can be extended to the pressureless Navier-Stokes-Poisson ... More
Vortical and Self-similar Flows of 2D Compressible Euler EquationsJan 18 2013This paper presents the vortical and self-similar solutions for 2D compressible Euler equations using the separation method. These solutions complement Makino's solutions in radial symmetry without rotation. The rotational solutions provide new information ... More
Blowup for the Euler and Euler-Poisson Equations with Repulsive Forces IIDec 23 2010In this paper, we continue to study the blowup problem of the $N$-dimensional compressible Euler or Euler-Poisson equations with repulsive forces, in radial symmetry. In details, we extend the recent result of "M.W. Yuen, \textit{Blowup for the Euler ... More
Perturbational Blowup Solutions to the 1-dimensional Compressible Euler EquationsDec 09 2010We study the construction of analytical non-radially solutions for the 1-dimensional compressible adiabatic Euler equations in this article. We could design the perturbational method to construct a new class of analytical solutions. In details, we perturb ... More
Stabilities for Euler-Poisson Equations with Repulsive Forces in R^NJan 03 2010This article extends the previous paper in "M.W. Yuen, \textit{Stabilities for Euler-Poisson Equations in Some Special Dimensions}, J. Math. Anal. Appl. \textbf{344} (2008), no. 1, 145--156.", from the Euler-Poisson equations for attractive forces to ... More
Perturbational Blowup Solutions to the 2-Component Camassa-Holm EquationsDec 08 2010In this article, we study the perturbational method to construct the non-radially symmetric solutions of the compressible 2-component Camassa-Holm equations. In detail, we first combine the substitutional method and the separation method to construct ... More
Rotational and Self-similar Solutions for the Compressible Euler Equations in R^3Sep 23 2014In this paper, we present rotational and self-similar solutions for the compressible Euler equations in R^3 using the separation method. These solutions partly complement Yuen's irrotational and elliptic solutions in R^3 [Commun. Nonlinear Sci. Numer. ... More
Security of Quantum Key DistributionFeb 24 2016The security issues facing quantum key distribution (QKD) are explained, herein focusing on those issues that are cryptographic and information theoretic in nature and not those based on physics. The problem of security criteria is addressed. It is demonstrated ... More
Analytical Blowup Solutions to the Isothermal Euler-Poisson Equations of Gaseous Stars in R^NMay 31 2009This article is the continued version of the analytical blowup solutions for 2-dimensional Euler-Poisson equations in "M.W. Yuen, Analytical Blowup Solutions to the 2-dimensional Isothermal Euler-Poisson Equations of Gaseous Stars, J. Math. Anal. Appl. ... More
Analytical Solutions to the Navier-Stokes EquationsNov 03 2008Feb 19 2009With the previous results for the analytical blowup solutions of the N-dimensional Euler-Poisson equations, we extend the similar structure to construct an analytical family of solutions for the isothermal Navier-Stokes equations and pressureless Navier-Stokes ... More
A Helium nanodrop bouncing off a wallJul 25 2003Aug 10 2003We investigate numerically the quantum collision between a stable Helium nanodrop and an infinitely hard wall in one dimension. The scattering outcome is compared to the same event omitting the quantum pressure. Only the quantum process reflects the effect ... More
Unconditional security in quantum bit commitmentJun 01 2001The commitment of bits between two mutually distrustful parties is a powerful cryptographic primitive with which many cryptographic objectives can be achieved. It is widely believed that unconditionally secure quantum bit commitment is impossible due ... More
Infinite Randomness Expansion and Amplification with a Constant Number of DevicesOct 24 2013Apr 01 2014We present a device-independent randomness expansion protocol, involving only a constant number of non-signaling quantum devices, that achieves \emph{infinite expansion}: starting with $m$ bits of uniform private randomness, the protocol can produce an ... More
Effect of Transmission Loss on The Fundamental Security of Quantum Key DistributionSep 06 2011It is shown that the effect of transmission loss has often not been properly taken into account in the security proofs on quantum key distribution. A class of general attacks to be called probabilistic re-sends attack is described that has not been accounted ... More
QBC3: An Unconditionally Secure Quantum Bit Commitment ProtocolFeb 07 2007Mar 19 2007This article describes a quantum bit commitment protocol, QBC3, based on entanglement destruction via forced measurements and proves its unconditional security. Some comments on the current status of the field are also made.
Mathematical Modeling of Physical and Engineering Systems in Quantum InformationFeb 06 2007Mar 19 2007Several concrete examples in quantum information are discussed to demonstrate the importance of proper modeling that relates the mathematical description to real-world applications. In particular, it is shown that some commonly accepted conclusions are ... More
Unconditionally Secure Quantum Bit Commitment Is PossibleJun 23 2000Oct 18 2000Bit commitment involves the submission of evidence from one party to another so that the evidence can be used to confirm a later revealed bit value by the first party, while the second party cannot determine the bit value from the evidence alone. It is ... More
Performance Analysis and Optimization for Interference Alignment over MIMO Interference Channels with Limited FeedbackFeb 03 2014In this paper, we address the problem of interference alignment (IA) over MIMO interference channels with limited channel state information (CSI) feedback based on quantization codebooks. Due to limited feedback and hence imperfect IA, there are residual ... More
Partial Third-Party Information Exchange with Network CodingFeb 15 2013In this paper, we consider the problem of exchanging channel state information in a wireless network such that a subset of the clients can obtain the complete channel state information of all the links in the network. We first derive the minimum number ... More
Joint Optimization of Spectrum Sensing and Accessing in Multiuser MISO Cognitive NetworksJun 30 2014In this paper, a joint spectrum sensing and accessing optimization framework for a multiuser cognitive network is proposed to significantly improve spectrum efficiency. For such a cognitive network, there are two important and limited resources that should ... More
A vanishing theorem for Dirac cohomology of standard modulesOct 01 2016This paper studies the Dirac cohomology of standard modules in the setting of graded Hecke algebras with geometric parameters. We prove that the Dirac cohomology of a standard module vanishes if and only if the module is not twisted-elliptic tempered. ... More
Self-similar Fragmentation Regulated by Magnetic Fields in a Massive Star Forming FilamentOct 24 2015Most molecular clouds are filamentary or elongated. Among those forming low-mass stars, their long axes tend to be either parallel or perpendicular to the large-scale (10-100 pc) magnetic field (B-field) in the surrounding inter cloud medium. This arises ... More
Geometric Bijections Between Spanning Trees and Break DivisorsSep 09 2015The Jacobian group ${\rm Jac}(G)$ of a finite graph $G$ is a group whose cardinality is the number of spanning trees of $G$. $G$ also has a tropical Jacobian which has the structure of a real torus; using the notion of break divisors, An et al. obtained ... More
Dangerous connections: on binding site models of infectious disease dynamicsJan 20 2016Jan 27 2016We formulate models for the spread of infection on networks that are amenable to analysis in the large population limit. We distinguish three different levels: (1) binding sites, (2) individuals, and (3) the population. In the tradition of Physiologically ... More
Some Physics And System Issues In The Security Analysis Of Quantum Key Distribution ProtocolsMay 07 2014In this paper we review a number of issues on the security of quantum key distribution (QKD) protocols that bear directly on the relevant physics or mathematical representation of the QKD cryptosystem. It is shown that the cryptosystem representation ... More
Security Significance of the Trace Distance Criterion in Quantum Key DistributionSep 13 2011Nov 09 2011The security significance of the trace distance security criterion $d$ is analyzed in terms of operational probabilities of an attacker's success in identifying different subsets of the generated key, both during the key generation process and when the ... More
KCQ: A New Approach to Quantum Cryptography I. General Principles and Key GenerationNov 10 2003Jul 30 2004A new approach to quantum cryptography to be called KCQ, keyed communication in quantum noise, is developed on the basis of quantum detection and communication theory for classical information transmission. By the use of a shared secret key that determines ... More
How to Build Unconditionally Secure Quantum Bit Commitment ProtocolsMay 23 2003Jan 14 2004The ``impossibility proof'' on unconditionally secure quantum bit commitment is critically analyzed. Many possibilities for obtaining a secure bit commitment protocol are indicated, purely on the basis of two-way quantum communications, which are not ... More
Fundamental Insecurity of Multi-Photon Sources Under Photon-Number Splitting Attacks in Quantum Key DistributionJul 30 2012Aug 06 2012A simple photon-number splitting attack is described which works on any lossy quantum key distribution system with a multi-photon source independently of the mean source photon number, and with no induced error rate. In particular, it cannot be detected ... More
Uncertainty Principle and the Standard Quantum LimitsOct 10 2005The role of the Uncertainty Principle is examined through the examples of squeezing, information capacity, and position monitoring. It is suggested that more attention should be directed to conceptual considerations in quantum information science and ... More
Finite Groups Embeddable in Division RingsMay 03 2000Finite groups that are embeddable in the multiplicative groups of division rings $K$ were completely determined by S. A. Amitsur in 1955. In case $K$ has characteristic $p>0$, the only possible finite subgroups of $K^*$ are cyclic groups, according to ... More
Blow-up Phenomena for Compressible Euler Equations with Non-vacuum Initial DataOct 17 2015In this article, we study the blowup phenomena of compressible Euler equations with non-vacuum initial data. Our new results, which cover a general class of testing functions, present new initial value blowup conditions. The corresponding blowup results ... More
Voltage-Controlled Berry Phases in Two Coupled Quantum DotsJan 25 2008The voltage-controlled Berry phases in two vertically coupled InGaAs/GaAs quantum dots are investigated theoretically. It is found that Berry phases can be changed dramatically from 0 to 2$\pi$ (or 2$\pi$ to 0) only simply by turning the external voltage. ... More
Applications of Partially Quenched Chiral Perturbation TheoryNov 17 1997Feb 24 1998Partially quenched theories are theories in which the valence- and sea-quark masses are different. In this paper we calculate the nonanalytic one-loop corrections of some physical quantities: the chiral condensate, weak decay constants, Goldstone boson ... More
Chiral perturbation theory for K+ to pi+ pi0 decay in the continuum and on the latticeFeb 14 1997May 16 1997In this paper we use one-loop chiral perturbation theory in order to compare lattice computations of the K+ to pi+ pi0 decay amplitude with the experimental value. This makes it possible to investigate three systematic effects that plague lattice computations: ... More
Exact joint laws associated with spectrally negative Levy processes and applications to insurance risk theoryJan 03 2011Feb 25 2014We consider the spectrally negative Levy processes and determine the joint laws for the quantities such as the first and last passage times over a fixed level, the overshoots and undershoots at first passage, the minimum, the maximum and the duration ... More
Binary Forms and the Hyperelliptic Superstring AnsatzNov 24 2009We give a hyperelliptic formulation of the Ansatz of D'Hoker and Phong. We give an explicit family of binary invariants, one for each genus, that satisfies this hyperelliptic Ansatz. We also prove that this is the unique family of weight eight binary ... More
Periodic Solutions of 2D Isothermal Euler-Poisson Equations with Possible Applications to Spiral and Disk-like GalaxiesAug 04 2014Compressible Euler-Poisson equations are the standard self-gravitating models for stellar dynamics in classical astrophysics. In this article, we construct periodic solutions to the isothermal ($\gamma=1$) Euler-Poisson equations in $R^{2}$ with possible ... More
Paramodular Cusp FormsDec 01 2009We classify Siegel modular cusp forms of weight two for the paramodular group K(p) for primes p< 600. We find that weight two Hecke eigenforms beyond the Gritsenko lifts correspond to certain abelian varieties defined over the rationals of conductor p. ... More
Line Solutions for the Euler and Euler-Poisson Equations with Multiple Gamma LawMay 20 2010In this paper, we study the Euler and Euler-Poisson equations in $R^{N}$, with multiple $\gamma$-law for pressure function: \begin{equation} P(\rho)=e^{s}\sum_{j=1}^{m}\rho^{\gamma_{j}}, \end{equation} where all $\gamma_{i+1}>\gamma_{i}\geq1$, is the ... More
On Two-way Communications for Cooperative Multiple Source Pairs Through a Multi-antenna RelayDec 10 2010We study amplified-and-forward (AF)-based two-way relaying (TWR) with multiple source pairs, which are exchanging information through the relay. Each source has single antenna and the relay has multi-antenna. The optimal beamforming matrix structure that ... More
Achieving Near-Capacity at Low SNR on a Multiple-Antenna Multiple-User ChannelJun 20 2008We analyze the sensitivity of the capacity of a multi-antenna multi-user system to the number of users being served. We show analytically that, for a given desired sum-rate, the extra power needed to serve a subset of the users at low SNR (signal-to-noise ... More
Pulsar Electrodynamics: an unsolved problemApr 13 2016Pulsar electrodynamics is reviewed emphasizing the role of the inductive electric field in an oblique rotator and the incomplete screening of its parallel component by charges, leaving `gaps' with $E_\parallel\ne0$. The response of the plasma leads to ... More
Impact of Stock Market Structure on Intertrade Time and Price DynamicsAug 28 2005The NYSE and NASDAQ stock markets have very different structures and there is continuing controversy over whether differences in stock price behaviour are due to market structure or company characteristics. As the influence of market structure on stock ... More
An Occluded Stacked Hourglass Approach to Facial Landmark Localization and Occlusion EstimationFeb 05 2018A key step to driver safety is to observe the driver's activities with the face being a key step in this process to extracting information such as head pose, blink rate, yawns, talking to passenger which can then help derive higher level information such ... More
Coarsening to Chaos-Stabilized FrontsJun 01 2010We investigate a model for pattern formation in the presence of Galilean symmetry proposed by Matthews and Cox [Phys.\ Rev.\ E \textbf{62}, R1473 (2000)], which has the form of coupled generalized Burgers and Ginzburg-Landau-type equations. With only ... More
Lipschitz equivalence of self-similar sets and hyperbolic boundariesMay 16 2012Dec 01 2012In [9] Kaimanovich introduced the concept of augmented tree on the symbolic space of a self-similar set. It is hyperbolic in the sense of Gromov, and it was shown in [13] that under the open set condition, a self-similar set can be identified with the ... More
Spectrality of Self-Similar TilesSep 16 2013We call a set $K \subset {\mathbb R}^s$ with positive Lebesgue measure a {\it spectral set} if $L^2(K)$ admits an exponential orthonormal basis. It was conjectured that $K$ is a spectral set if and only if $K$ is a tile (Fuglede's conjecture). Despite ... More
Temperature Dependence of Violation of Bell's Inequality in Coupled Quantum Dots in a MicrocavityMay 22 2007Bell's inequality in two coupled quantum dots within cavity QED, including Forster and exciton-phonon interactions, is investigated theoretically. It is shown that the environmental temperature has a significant impact on Bell's inequality.
Critical exponents of induced Dirichlet forms on self-similar setsDec 06 2016In a previous paper, we studied certain random walks on the hyperbolic graphs $X$ associated with the self-similar sets $K$, and showed that the discrete energy ${\mathcal E}_X$ on $X$ has an induced energy form ${\mathcal E}_K$ on $K$. The domain of ... More
Quantum process tomography of molecular dimers from two-dimensional electronic spectroscopy I: General theory and application to homodimersJan 14 2011Is it possible to infer the time evolving quantum state of a multichromophoric system from a sequence of two-dimensional electronic spectra (2D-ES) as a function of waiting time? Here we provide a positive answer for a tractable model system: a coupled ... More
On Igusa zeta functions of monomial idealsSep 11 2005Sep 22 2006We show that the real parts of the poles of the Igusa zeta function of a monomial ideal can be computed from the torus-invariant divisors on the normalized blowing-up along the ideal. Moreover, we show that every such number is a root of the Bernstein-Sato ... More
Blowup of Regular Solutions for the Relativistic Euler-Poisson EquationsSep 04 2015In this paper, we study the blowup phenomena for the regular solutions of the isentropic relativistic Euler-Poisson equations with a vacuum state in spherical symmetry. Using a general family of testing functions, we obtain new blowup conditions for the ... More
Exploiting Large-Scale MIMO Techniques for Physical Layer Security with Imperfect Channel State InformationJul 28 2014In this paper, we study the problem of physical layer security in large-scale multiple input multiple output (LS-MIMO) systems. The large number of antenna elements in LS-MIMO system is exploited to enhance transmission security and improve system performance, ... More
Resource Allocation for Cost Minimization in Limited Feedback MU-MIMO Systems with Delay GuaranteeNov 05 2013In this paper, we design a resource allocation framework for the delay-sensitive Multi-User MIMO (MU-MIMO) broadcast system with limited feedback. Considering the scarcity and interrelation of the transmit power and feedback bandwidth, it is imperative ... More
Adaptive Mode Selection in Multiuser MISO Cognitive Networks with Limited Cooperation and FeedbackOct 16 2013In this paper, we consider a multiuser MISO downlink cognitive network coexisting with a primary network. With the purpose of exploiting the spatial degree of freedom to counteract the inter-network interference and intra-network (inter-user) interference ... More
A Continuous Vector-Perturbation for Multi-Antenna Multi-User CommunicationJun 23 2008The sum-rate of the broadcast channel in a multi-antenna multi-user communication system can be achieved by using precoding and adding a regular perturbation to the data vector. The perturbation can be removed by the modulus function, thus transparent ... More
Non-homogeneous distributed storage systemsAug 10 2012This paper describes a non-homogeneous distributed storage systems (DSS), where there is one super node which has a larger storage size and higher reliability and availability than the other storage nodes. We propose three distributed storage schemes ... More
Jacobi forms that characterize paramodular formsSep 15 2012The Fourier Jacobi expansions of paramodular forms are characterized from among all formal series of Jacobi forms by two conditions on the Fourier coeffcients of the Jacobi forms: a growth condition and a set of linear relations. Examples, both theoretical ... More
Dynamics of precipitation pattern formation at geothermal hot springsJan 13 2006May 26 2006We formulate and model the dynamics of spatial patterns arising during the precipitation of calcium carbonate from a supersaturated shallow water flow. The model describes the formation of travertine deposits at geothermal hot springs and rimstone dams ... More
On differential characteristic classesNov 15 2013Oct 16 2014In this paper we give explicit formulas of differential characteristic classes of principal $G$-bundles with connections and prove their expected properties. In particular, we obtain explicit formulas for differential Chern classes, differential Pontryagin ... More
Charge transfer satellites in x-ray spectra of transition metal oxidesNov 19 2013Strongly correlated materials such as transition metal oxides (TMOs) often exhibit large satellites in their x-ray photoemission (XPS) and x-ray absorption spectra (XAS). These satellites arise from localized charge-transfer (CT) excitations that accompany ... More
Time complexity of concurrent programsNov 16 2015We study the problem of automatically computing the time complexity of concurrent object-oriented programs. To determine this complexity we use intermediate abstract descriptions that record relevant information for the time analysis (cost of statements, ... More
Landmark-matching Transformation with Large Deformation via n-dimensional Quasi-conformal MapsFeb 27 2014May 11 2015We propose a new method to obtain landmark-matching transformations between n-dimensional Euclidean spaces with large deformations. Given a set of feature correspondences, our algorithm searches for an optimal folding-free mapping that satisfies the prescribed ... More
Multifractal characterisation of length sequences of coding and noncoding segments in a complete genomeAug 28 2001The coding and noncoding length sequences constructed from a complete genome are characterised by multifractal analysis. The dimension spectrum $D_{q}$ and its derivative, the 'analogous' specific heat $C_{q}$, are calculated for the coding and noncoding ... More
Functional Renormalization Group Analysis of the Half-filled One-dimensional Extended Hubbard ModelMay 16 2005Feb 14 2006We study the phase diagram of the half-filled one-dimensional extended Hubbard model at weak coupling using a novel functional renormalization group (FRG) approach. The FRG method includes in a systematic manner the effects of the scattering processes ... More
On an index theorem by BismutJan 07 2015Jul 16 2015In this paper we give a proof of an index theorem by Bismut. As a consequence we obtain another proof of the Grothendieck-Riemann-Roch theorem in differential cohomology.
Robust Randomness Amplifiers: Upper and Lower BoundsMay 28 2013Jun 23 2013A recent sequence of works, initially motivated by the study of the nonlocal properties of entanglement, demonstrate that a source of information-theoretically certified randomness can be constructed based only on two simple assumptions: the prior existence ... More
Antisymmetric Paramodular Forms of Weights 2 and 3Sep 14 2016We define an algebraic set in $23$~dimensional projective space whose $\mathbb Q$-rational points correspond to meromorphic, antisymmetric, paramodular Borcherds products. We know two lines inside this algebraic set. Some rational points on these lines ... More
Borcherds Products EverywhereDec 22 2013We prove the Borcherds Products Everywhere Theorem, Theorem 6.6, that constructs holomorphic Borcherds Products from certain Jacobi forms that are theta blocks without theta denominator. The proof uses generalized valuations from formal series to partially ... More
Siegel Paramodular Forms of Weight 2 and Squarefree LevelDec 03 2016We compute the space $S_2(K(N))$ of weight $2$ Siegel paramodular cusp forms of squarefree level $N<300$. In conformance with the paramodular conjecture of A. Brumer and K. Kramer, the space is only the additive (Gritsenko) lift space of the Jacobi cusp ... More
Tilings of the Sphere by Edge Congruent PentagonsJan 04 2013Apr 14 2013We study edge-to-edge tilings of the sphere by edge congruent pentagons, under the assumption that there are tiles with all vertices having degree 3. We develop the technique of neighborhood tilings and apply the technique to completely classify edge ... More
Reversible Superconductivity in Electrochromic Indium-Tin Oxide FilmsMar 21 2012Oct 09 2012Transparent conductive indium tin oxide (ITO) thin films, electrochemically intercalated with sodium or other cations, show tunable superconducting transitions with a maximum $T_c$ at 5 K. The transition temperature and the density of states, $D(E_F)$ ... More
Pomeranchuk Instability in a non-Fermi Liquid from HolographyMar 14 2012Sep 17 2012The Pomeranchuk instability, in which an isotropic Fermi surface distorts and becomes anisotropic due to strong interactions, is a possible mechanism for the growing number of experimental systems which display transport properties that differ along the ... More
Neutral Order Parameters in Metallic Criticality in d=2+1 from a Hairy Electron StarJun 16 2011We use holography to study the spontaneous condensation of a neutral order parameter in a (2+1)-dimensional field theory at zero-temperature and finite density, dual to the electron star background of Hartnoll and Tavanfar. An appealing feature of this ... More
Geometric phase of a central spin coupled to an antiferromagnetic environmentMar 05 2010Using the spin-wave approximation, we study the geometric phase (GP) of a central spin (signal qubit) coupled to an antiferromagnetic (AF) environment under the application of an external global magnetic field. The external magnetic field affects the ... More
Influence of an external magnetic field on the decoherence of a central spin coupled to an antiferromagnetic environmentJun 07 2007Using the spin wave approximation, we study the decoherence dynamics of a central spin coupled to an antiferromagnetic environment under the application of an external global magnetic field. The external magnetic field affects the decoherence process ... More
Harmonics suppression effect of the quasi-periodic undulator in SASE free-electron-laserMay 03 2013In this paper, the harmonics suppression effect of QPUs in SASE FEL is investigated. The numerical results show that the harmonics power is reduced by using QPUs, but the fundamental radiation power also has a pronounced decrease as the saturation length ... More
Particle-hole cumulant approach for inelastic losses in x-ray spectraApr 22 2016Inelastic losses in core level x-ray spectra arise from many-body excitations, leading to broadening and damping as well as satellite peaks in x-ray photoemission (XPS) and x-ray absorption (XAS) spectra. Here we present a practical approach for calculating ... More
Generalized particle/hole cumulant approximation for the electron Green's functionJan 31 2014The cumulant expansion is a powerful approach for including correlation effects in electronic structure calculations beyond the GW approximation. However, current implementations are incomplete since they ignore terms that lead to partial occupation numbers ... More
Holographic Stress Tensor for Kerr-AdS Black Holes and Local Failure on IR-UV ConnectionMay 26 2000Jun 07 2000We show that in general holographic stress tensor may contain a new term of divergence of a spacelike unit normal acceleration. Then, it is shown that in contrast to previous descriptions, a new stress tensor for Kerr-AdS solutions can be a traceless ... More
A Proof of the Generalized Second Law for Two-Dimensional Black HolesMar 16 2001Apr 25 2001We investigate the generalized second law for two-dimensional black holes in equilibrium (Hartle-Hawking) and nonequilibrium (Unruh) with the heat bath surrounding the black holes. We obtain a simple expression for the change of total entropy in terms ... More
Multifractal characterisation of complete genomesAug 28 2001This paper develops a theory for characterisation of DNA sequences based on their measure representation. The measures are shown to be random cascades generated by an infinitely divisible distribution. This probability distribution is uniquely determined ... More
Dominant Superconducting Fluctuations in the One-Dimensional Extended Holstein-Extended Hubbard modelJan 23 2013The search for realistic one-dimensional (1D) models that exhibit dominant superconducting (SC) fluctuations effects has a long history. In these 1D systems, the effects of commensurate band fillings--strongest at half-filling--and electronic repulsions ... More