Results for "Pei Miao"

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Noncommutative Differential Calculus for D-brane in Non-Constant B Field BackgroundMay 19 2001Jun 05 2001In this paper we try to construct noncommutative Yang-Mills theory for generic Poisson manifolds. It turns out that the noncommutative differential calculus defined in an old work is exactly what we need. Using this calculus, we generalize results about ... More
Large N Expansion From Fuzzy AdS_2May 29 2000We study the quantum analogue of primary fields and their descendants on fuzzy AdS_2, proposed in hep-th/0004072. Three-point vertices are calculated and shown to exhibit the conventional 1/N expansion as well as nonperturtive effects in large N, thus ... More
Fuzzy Spheres in AdS/CFT Correspondence and Holography from NoncommutativityApr 11 2000Apr 29 2000We show that the existent fuzzy S^2 and S^4 models are natural candidates for the quantum geometry on the corresponding spheres in AdS/CFT correspondence. These models fit nicely the data from the dipole mechanism for the stringy exclusion principle. ... More
Graviton one-loop effective action and inflationary dynamicsJul 02 2008We consider the one-loop effective action due to gravitons in a FLRW background with constant epsilon=-(dH/dt)/H^2. By expanding around epsilon=0 (corresponding to an expansion around de Sitter space), we can study how the deviation from de Sitter space ... More
The Quantum-Corrected Fermion Mode Function during InflationMay 05 2007My project computed the one loop fermion self-energy for massless Dirac + Einstein in the presence of a locally de Sitter background. I employed dimensional regularization and obtain a fully renormalized result by absorbing all divergences with Bogliubov, ... More
Topological Hybrid Silicon MicrolasersSep 08 2017Topological photonics provides a robust framework for strategically controlling light confinement and propagation dynamics. By exploiting the marriage between this notion and symmetry-constrained mode competition in an active setting, we experimentally ... More
Supersymmetric microring laser arraysFeb 08 2019Coherent combination of emission power from an array of coupled semiconductor lasers operating on the same chip is of fundamental and technological importance. In general, the nonlinear competition among the array supermodes can entail incoherence and ... More
On classical global solutions of nonlinear wave equations with large dataJul 16 2014Dec 29 2015This paper studies the Cauchy problem for systems of semi-linear wave equations on $\mathbb{R}^{3+1}$ with nonlinear terms satisfying the null conditions. We construct future global-in-time classical solutions with arbitrarily large initial energy. The ... More
Strange Work in Strange Places: Quantum Field Theory in Curved SpaceMay 24 2015Astronomers seem to be observing the fossilized remnants of quantum gravitational processes which took place during the epoch of {\it primordial inflation} that is conjectured to have occurred during the first $10^{-32}$ seconds of cosmic history. We ... More
A Simple Operator Check of the Effective Fermion Mode Function during InflationMar 16 2008Jun 25 2008We present a relatively simple operator formalism which reproduces the leading infrared logarithm of the one loop quantum gravitational correction to the fermion mode function on a locally de Sitter background. This rule may serve as the basis for an ... More
Leading Log Solution for Inflationary YukawaFeb 27 2006May 11 2008We generalize Starobinskii's stochastic technique to the theory of a massless, minimally coupled scalar interacting with a massless fermion in a locally de Sitter geometry. The scalar is an ``active'' field that can engender infrared logarithms. The fermion ... More
Probing charged impurities in suspended graphene using Raman spectroscopyDec 22 2008Feb 19 2009Charged impurity (CI) scattering is one of the dominant factors that affect the carrier mobility in graphene. In this paper, we use Raman spectroscopy to probe the charged impurities in suspended graphene. We find that the 2D band intensity is very sensitive ... More
Gravitons Enhance Fermions during InflationMar 31 2006May 11 2008We solve the effective Dirac equation for massless fermions during inflation in the simplest gauge, including all one loop corrections from quantum gravity. At late times the result for a spatial plane wave behaves as if the classical solution were subjected ... More
Tunable Quantum Spin Hall Effect via Strain in two-Dimensional Arsenene MonolayerOct 16 2015The search for new quantum spin Hall (QSH) phase and effective manipulations of their edge states are very important for both fundamental sciences and practical applications. Here, we use first-principles calculations to study the strain-driven topological ... More
The Fermion Self-Energy during InflationNov 26 2005Feb 06 2006We compute the one loop fermion self-energy for massless Dirac + Einstein in the presence of a locally de Sitter background. We employ dimensional regularization and obtain a fully renormalized result by absorbing all divergences with BPHZ counterterms. ... More
The universal quantum driving force to speed up a quantum computation -- The unitary quantum dynamicsMay 18 2011Nov 22 2011It is shown in the paper that the unitary quantum dynamics in quantum mechanics is the universal quantum driving force to speed up a quantum computation. This assertion supports strongly in theory that the unitary quantum dynamics is the fundamental and ... More
Introduction to the multiple-quantum operator spacesJul 06 2009Jul 11 2009The multiple-quantum NMR spectroscopy has an extensive application in determination of the bio-macro-molecular structures and in the investigation of the properties of a variety of physical materials. In quantum computation the multiple-quantum transition ... More
Ultra-broadband Heteronuclear Hartmann-Hahn polarization transferMar 16 2002May 08 2002It is showed on the basis of the multiple-quantum operator algebra space formalism that ultra-broadband heteronuclear Hartmann-Hahn polarization transfer could be achieved by the amplitude- and frequency-modulation quasi-adiabatic excitation (90 degree) ... More
A polynomial-time solution to the parity problem on an NMR quantum computerAug 26 2001Sep 06 2001An efficient quantum algorithm is proposed to solve in polynomial time the parity problem, one of the hardest problems both in conventional quantum computation and in classical computation, on NMR quantum computers. It is based on the quantum parallelism ... More
Solving the quantum search problem in polynomial time on an NMR quantum computerJun 16 2002The quantum search problem is an important problem due to the fact that a general NP problem can be solved efficiently by an unsorted quantum search algorithm. Here it has been shown that the quantum search problem could be solved in polynomial time on ... More
On Existence of Static Metric Extensions in General RelativitySep 17 2003Motivated by problems related to quasi-local mass in general relativity, we study the static metric extension conjecture proposed by R. Bartnik \cite{Bartnik_energy}. We show that, for any metric on $\bar{B}_1$ that is close enough to the Euclidean metric ... More
A Defect in Dempster-Shafer TheoryFeb 27 2013By analyzing the relationships among chance, weight of evidence and degree of beliefwe show that the assertion "probability functions are special cases of belief functions" and the assertion "Dempster's rule can be used to combine belief functions based ... More
The excitation operator method in the spin dynamics of the one-dimensional XXZ modelJul 08 2012Jul 12 2012We develop the excitation operator method, which is designed to solve the Heisenberg equation of motion by constructing the excitation operators. We use it to study the spin dynamics in the one-dimensional XXZ model. We find the diffusive spin transport ... More
The breakdown of the zeroth law of thermodynamics and the definition of temperature in small quantum systemsMay 20 2012Oct 11 2012We study two small quantum systems coupled to the same reservoir which is in thermal equilibrium. By studying the particle density and the energy density in the two systems before and after they contact each other, we find that the two systems are not ... More
Local temperature and chemical potential inside a mesoscopic device driven out of equilibriumMay 03 2011Aug 20 2011In this paper we introduce a method of calculating the local temperature and chemical potential inside a mesoscopic device out of equilibrium. We show how to check the conditions of local thermal equilibrium as the whole system is out of equilibrium. ... More
Solving real time evolution problems by constructing excitation operatorsSep 03 2010Apr 21 2012In this paper we study the time evolution of an observable in the interacting fermion systems driven out of equilibrium. We present a method for solving the Heisenberg equations of motion by constructing excitation operators which are defined as the operators ... More
A symmetry property for q-weighted Robinson-Schensted algorithms and other branching insertion algorithmsJun 10 2013Jun 11 2013In O'Connell-Pei(2013) a q-weighted version of the Robinson-Schensted algorithm was introduced. In this paper we show that this algorithm has a symmetry property analogous to the well known symmetry property of the normal Robinson-Schensted algorithm. ... More
A theory of nonequilibrium steady states in quantum chaotic systemsJul 18 2016Nonequilibrium steady state (NESS) is a quasistationary state, in which exist currents that continuously produce entropy, but the local observables are stationary everywhere. We propose a theory of NESS under the framework of quantum chaos. In an isolated ... More
A Suggestion for Modification of Vafa-Witten TheoryDec 05 1995Using the Mathai-Quillen formalism we reexamine the twisted N=4 supersymmetric model of Vafa-Witten theory. Smooth out the relation between the supersymmetric action and the path integral representation of the Thom class.
The excitation operator approach to non-Markovian dynamics of quantum impurity models in the Kondo regimeSep 18 2012We present a numerical method for studying the real time dynamics of a small interacting quantum system coupled to an infinite fermionic reservoir. By building an orthonormal basis in the operator space, we turn the Heisenberg equation of motion into ... More
Variations of Gauss-Codazzi-Ricci Equations in Kaluza-Klein Reduction (String Theory) and Cauchy Problem (General Relativity)May 09 2007We find a kind of variations of Gauss-Codazzi-Ricci equations suitable for Kaluza-Klein reduction and Cauchy problem. Especially the counterpart of extrinsic curvature tensor has antisymmetric part as well as symmetric one. If the dependence of metric ... More
On the Uncertainty Principle for Continuous Quantum MeasurementMay 08 2016Aug 24 2016For continuous quantum measurements, there is a general Heisenberg uncertainty relation that constrains the quantum fluctuation of detectors with linear response, which is a generalization of the fluctuation-dissipation theorem to the scenarios far from ... More
The STIRAP-based unitary decelerating and accelerating processes of a single free atomJul 01 2007May 10 2009A STIRAP-based unitary decelerating (accelerating) process consists of a train of the standard three-state STIRAP pulse sequences which may act as the basic unitary decelerating (accelerating) sequences. The present work is focused on investigating analytically ... More
The basic principles to construct a generalized state-locking pulse field and simulate efficiently the reversible and unitary halting protocol of a universal quantum computerJul 20 2006Nov 27 2006It has been shown (Arxiv: quant-ph/0507236) that a universal quantum computer could be powerful enough to solve efficiently the quantum search problem, and the reversible and unitary halting protocol based on the state-locking pulse field is the key component ... More
Jung's Theorem and fixed points for $p$-uniformly convex spacesMay 07 2013We introduce the classical Jung theorem and fixed point theorems and prove similar ones for $p$-uniformly convex spaces.
Fractal Dimension Pattern Based Multiresolution Analysis for Rough Estimator of Person-Dependent Audio Emotion RecognitionJul 01 2016As a general means of expression, audio analysis and recognition has attracted much attentions for its wide applications in real-life world. Audio emotion recognition (AER) attempts to understand emotional states of human with the given utterance signals, ... More
Correspondence Principle in a PP-wave BackgroundMay 06 2002May 29 2002We discuss the correspondence point between a string state and a black hole, in a pp-wave background, and find that the answer is considerably different from that in a flat spacetime background.
Dimensional Reduction via Noncommutative Spacetime: Bootstrap and HolographyMar 14 2001Mar 26 2001Unlike noncommutative space, when space and time are noncommutative, it seems necessary to modify the usual scheme of quantum mechanics. We propose in this paper a simple generalization of the time evolution equation in quantum mechanics to incorporate ... More
Energy-Momentum Conservation and Holographic S-MatrixApr 26 1999We investigate the consequence of the energy-momentum conservation law for the holographic S-matrix from AdS/CFT correspondence. It is shown that the conservation law is not a natural consequence of conformal invariance in the large N limit. We predict ... More
Comments on Supersymmetric Yang-Mills Theory on a Noncommutative TorusFeb 09 1998D0-brane theory on a torus with a nonvanishing B field is embedded into a string theory in the weak coupling limit. It is shown that the usual supersymmetric Yang-Mills theory on a noncommutative torus can not be the whole story. The Born-Infeld action ... More
Dirichlet StringsJul 19 1993Nov 23 1993Strings propagating along surfaces with Dirichlet boundaries are studied in this paper. Such strings were originally proposed as a possible candidate for the QCD string. Our approach is different from previous ones and is simple and general enough, with ... More
A proposal on the topological sector of 2d stringJan 08 1993Jan 12 1993The field content of the two dimensional string theory consists of the dynamical tachyon field and some nonpropagating fields which consist in the topological sector of this theory. We propose in this paper to study this topological sector as a spacetime ... More
Black Holes and Spacetime Physics in String/M TheoryJun 05 2000In addition to briefly reviewing recent progress in studying black hole physics in string/M theory, we describe several robust features pertaining to spacetime physics that one can glean by studying quantum physics of black holes. In particular, we review ... More
Gauge Symmetries and Amplitudes in N=2 StringsApr 11 1992Picture changed operators are discussed in $N=2$ strings with space-time signature $(2,2)$. A gauge symmetry algebra is derived in a background of torus space-time $T^{2,2}$ and its simple representation on the picture changed operators is given. Simple ... More
Decoherence of the two-level system coupled to a fermionic reservoir and the information transfer from it to the environmentDec 24 2010Feb 01 2011We study the evolution of reduced density matrix of an impurity coupled to a Fermi sea after the coupling is switched on at time $t=0$. We find the non-diagonal elements of the reduced density matrix decay exponentially, and the decay constant is the ... More
Belief Revision in Probability TheoryMar 06 2013In a probability-based reasoning system, Bayes' theorem and its variations are often used to revise the system's beliefs. However, if the explicit conditions and the implicit conditions of probability assignments `me properly distinguished, it follows ... More
Induction and restriction functors for cellular categoriesJan 23 2017Jan 25 2017Cellular categories are a generalization of cellular algebras, which include a number of important categories such as (affine)Temperley-Lieb categories, Brauer diagram categories, partition categories, the categories of invariant tensors for certain quantised ... More
Continuous data assimilation for the 3D primitive equations of the oceanMay 13 2018In this article, we show that the continuous data assimilation algorithm is valid for the 3D primitive equations of the ocean. Namely, the $L^2$ norm of the assimilated solution converge to that of the reference solution at an exponential rate in time. ... More
Matrix Theory in a Constant C Field BackgroundNov 19 1999Dec 04 1999D0-branes moving in a constant antisymmetric C field are found to be described by quantum mechanics of the supersymmetric matrix model with a similarity transformation. Sometimes this similarity transformation is singular or ill-defined and cannot be ... More
P-P' Strings in M(atrix) TheoryJun 10 1997Dec 02 1997We study the off-diagonal blocks in the M(atrix) model that are supposed to correspond to open strings stretched between a Dp-brane and a Dp'-brane. It is shown that the spectrum, including the quantum numbers, of the zero modes in the off-diagonal blocks ... More
Technical Report: Representing SES Cases Using OntologyJan 31 2016Socio-ecological System (SES) research studies the interaction between environment, users, and governance of environment resources. Data produced during the research cycle can be both long-tail (e.g. heterogeneous) and longitudinal data. For example, ... More
Unitary manipulation of a single atom in time and space --- The spatially-selective and internal-state-selective triggering pulsesSep 15 2013Sep 17 2013A spatially-selective and internal-state-selective triggering pulse is an important component to realize the unitary dynamical state-locking process which may be used to realize the reversible and unitary halting protocol and construct the unstructured ... More
An explicit criterion for existence of the Magnus solution for a coupled spin system under a time-dependent radiofrequency pulseApr 22 2012The explicit criterion is derived in detail for the convergence of the Magnus expansion and the existence of the Magnus solution in the interaction picture, i.e., the exponential propagator in the weakly coupled spin (I=1/2) system SnAMX... (n=1,2,3,...) ... More
Universal construction of quantum computational networks in superconducting Josephson junctionsMar 24 2000Any quantum computational network can be constructed with a sequence of the two-qubit diagonal quantum gates and one-qubit gates in two-state quantum systems. The universal construction of these quantum gates in the quantum systems and of the quantum ... More
Feynman Algorithm Implementation for Comparison with Euler in a Uniform Elastic Two-Layer 2D and 3D Object Dynamic Deformation Framework in OpenGL with GUIJun 17 2009We implement for comparative purposes the Feynman algorithm within a C++-based framework for two-layer uniform facet elastic object for real-time softbody simulation based on physics modeling methods. To facilitate the comparison, we implement initial ... More
Dynamic Deformation of Uniform Elastic Two-Layer ObjectsJul 24 2009Jul 25 2009This thesis presents a two-layer uniform facet elastic object for real-time simulation based on physics modeling method. It describes the elastic object procedural modeling algorithm with particle system from the simplest one-dimensional object, to more ... More
Nonminimal Inflation and the Running Spectral IndexJul 24 2006We study a class of models in which the inflaton is minimally coupled to gravity with a term $f(R)\vp^2$. We focus in particular on the case when $f\sim R^2$, the expansion of the scale factor is driven by the usual potential energy, while the rolling ... More
Kaluza-Klein dimensional reduction and Gauss-Codazzi-Ricci equationsMay 29 2008In this paper we imitate the traditional method which is used customarily in the General Relativity and some mathematical literatures to derive the Gauss-Codazzi-Ricci equations for dimensional reduction. It would be more distinct concerning geometric ... More
Relative Rips MachineDec 23 2016We study isometric actions of finitely presented groups on $\mathbb{R}$-trees. In this paper, we develop a relative version of the Rips machine to study $\textit{pairs}$ of such actions. An important example of a $\textit{pair}$ is a group action on an ... More
Unitarily manipulating in time and space a Gaussian wave-packet motional state of a single atom in a quadratic potential fieldAug 16 2007Oct 12 2007The paper first discusses theoretically the off-resonance selective excitation method that is dependent on the atomic internal states and used to generate approximately a standard coherent state of harmonic oscillator. The coherent average method then ... More
Efficient multiple-quantum transition processes in an n-qubit spin systemNov 07 2004Nov 23 2004The whole Hilbert state space of an n-qubit spin system can be divided into (n+1) state subspaces according to the angular momentum theory of quantum mechanics. Here it is shown that any unknown state in such a state subspace, whose dimensional size is ... More
Universal construction of unitary transformation of quantum computation with one- and two-body interactionsMar 17 2000Apr 18 2000Any unitary transformation of quantum computational networks is explicitly decomposed, in an exact and unified form, into a sequence of a limited number of one-qubit quantum gates and the two-qubit diagonal gates that have diagonal unitary representation ... More
A Note on Existence and Non-existence of Minimal Surfaces in Some Asymptotically Flat 3-manifoldsJan 19 2006Motivated by problems on apparent horizons in general relativity, we prove the following theorem on minimal surfaces: Let $g$ be a metric on the three-sphere $S^3$ satisfying $Ric(g) \geq 2 g$. If the volume of $(S^3, g)$ is no less than one half of the ... More
Variational Effect of Boundary Mean Curvature on ADM Mass in General RelativitySep 18 2003We extend the idea and techniques in \cite{Miao} to study variational effect of the boundary geometry on the ADM mass of an asymptotically flat manifold. We show that, for a Lipschitz asymptotically flat metric extension of a bounded Riemannian domain ... More
Kaldi+PDNN: Building DNN-based ASR Systems with Kaldi and PDNNJan 27 2014The Kaldi toolkit is becoming popular for constructing automated speech recognition (ASR) systems. Meanwhile, in recent years, deep neural networks (DNNs) have shown state-of-the-art performance on various ASR tasks. This document describes our open-source ... More
PP-wave Black holes and The Matrix ModelDec 31 2002May 14 2003We discuss the sizes of a black hole in the M theory pp-wave background, and how the transverse size can be reproduced in the matrix model.
Boundary States of D-Branes and Dy-StringsOct 22 1995Polchinski's recent construction of Dirichlet-branes of R-R charges, together with Witten's mechanism for forming bound states of both NS-NS charges and R-R charges, provides a rigorous method to treat these dy-branes. We construct the massless sector ... More
Macroscopic Black Holes, Microscopic Black Holes and Noncommutative MembraneNov 13 2003May 29 2004We study the stretched membrane of a black hole as consisting of a perfect fluid. We find that the pressure of this fluid is negative and the specific heat is negative too. A surprising result is that if we are to assume the fluid be composed of some ... More
Fuzzy Gravitons From Uncertain SpacetimeMar 20 2000Apr 03 2000The recently proposed remarkable mechanism explaining ``stringy exclusion principle" on an Anti de Sitter space is shown to be another beautiful manifestation of spacetime uncertainty principle in string theory as well as in M theory. Put in another way, ... More
't Hooft vortices and phases of large N gauge theoryApr 27 1998It is shown that a pair of vortex and anti-vortex is completely screened in 2+1 dimensional Yang-Mills theory and 3+1 dimensional Yang-Mills theory in the strong coupling limit, based on the recent conjecture of Maldacena. This is consistent with the ... More
Dirichlet Boundary State in Linear Dilaton BackgroundDec 06 1995Dec 30 1995Dirichlet-branes have emerged as important objects in studying nonperturbative string theory. It is important to generalize these objects to more general backgrounds other than the usual flat background. The simplest case is the linear dilaton condensate. ... More
Quenched Two Dimensional Supersymmetric Yang-Mills TheoryJun 09 1995By studying the pure Yang-Mills theory on a circle, as well as an adjoint scalar coupled to the gauge field on a circle, we propose a quenching prescription in which the combination of the spatial component of the gauge field and $P$ is treated as a dynamic ... More
A prime factorization based on quantum dynamics on a spin ensemble (I)Feb 20 2003In this paper it has been described how to use the unitary dynamics of quantum mechanics to solve the prime factorization problem on a spin ensemble without any quantum entanglement. The ensemble quantum computation for the prime factorization is based ... More
Quantum search processes in the cyclic group state spacesJul 25 2005Sep 21 2005The hardness to solve an unstructured quantum search problem by a standard quantum search algorithm mainly originates from the low efficiency to amplify the amplitude of the marked state by the oracle unitary operation associated with other known quantum ... More
Universal construction for the unsorted quantum search algorithmsJan 26 2001Jun 20 2001The multiple-quantum operator algebra formalism has been exploited to construct generally an unsorted quantum search algorithm. The exponential propagator and its corresponding effective Hamiltonian are constructed explicitly that describe in quantum ... More
A convenient method to prepare the effective pure state in a quantum ensembleAug 23 2000A simple method is proposed to prepare conveniently the effective pure state |00...0><0...00| with any number of qubits in a quantum ensemble. The preparation is based on the temporal averaging (Knill, Chuang, and Laflamme, Phys.Rev.A 57, 3348(1998)). ... More
Positive Mass Theorem on Manifolds admitting Corners along a HypersurfaceDec 05 2002Dec 24 2003We study a class of non-smooth asymptotically flat manifolds on which metrics fails to be $C^1$ across a hypersurface $\Sigma$. We first give an approximation scheme to mollify the metric, then we prove that the Positive Mass Theorem still holds on these ... More
A Class of Cosmological Matrix ModelsJun 30 2005Oct 24 2005We discuss a class of matrix models describing cosmology with a light-like singularity, generalizing the model proposed by Craps et al. in hep-th/0506180.
Explicit expressions for a family of Bell polynomials and derivatives of some functionsApr 27 2014May 11 2014In the paper, the authors first inductively establish explicit formulas for derivatives of the arc sine function, then derive from these explicit formulas explicit expressions for a family of Bell polynomials related to the square function, and finally ... More
A New Model of Holographic Dark Energy with Action PrincipleOct 03 2012Nov 23 2012We propose a new model of holographic dark energy with an action. It is the first time that one can derive a HDE model from the action principle. The puzzles of causality and circular logic about HDE have been completely solved in this model. The evolution ... More
Metamaterials Mimicking Dynamic Spacetime, D-brane and Noncommutativity in String TheoryMay 31 2010Feb 03 2011We propose an executable scheme to mimic the expanding cosmos in 1+2 dimensions in laboratory. Furthermore, we develop a general procedure to use nonlinear metamaterials to mimic D-brane and noncommutativity in string theory.
More studies on Metamaterials Mimicking de Sitter spaceDec 24 2009Apr 15 2010We estimate the dominating frequencies contributing to the Casimir energy in a cavity of metamaterials mimicking de Sitter space, by solving the eigenvalue problem of Maxwell equations. It turns out the dominating frequencies are the inverse of the size ... More
Violation of the first law of black hole thermodynamics in $f(T)$ gravityJul 04 2011Nov 17 2011We prove that, in general, the first law of black hole thermodynamics, $\delta Q=T\delta S$, is violated in $f(T)$ gravity. As a result, it is possible that there exists entropy production, which implies that the black hole thermodynamics can be in non-equilibrium ... More
Degrees of freedom of $f(T)$ gravityMay 30 2011Jul 29 2011We investigate the Hamiltonian formulation of $f(T)$ gravity and find that there are five degrees of freedom. The six first class constraints corresponding to the local Lorentz transformation in Teleparallel gravity become second class constraints in ... More
Inequalities on the boundary of bodies surrounding horizonsOct 24 2016Inspired by the method of Mantoulidis-Schoen \cite{schoen-mant}, we apply the Riemannian Penrose inequality to derive inequalities on the boundary of compact Riemannian $3$-manifolds with nonnegative scalar curvature, whose boundary consists of minimal ... More
The covariant and on-shell statistics in kappa-deformed spacetimeApr 20 2010It has been a long-standing issue to construct the statistics of identical particles in $\kappa$-deformed spacetime. In this letter, we investigate different ideas on this problem. Following the ideas of Young and Zegers, we obtain the covariant and on-shell ... More
On The Capacity of Surfaces in Manifolds with Nonnegative Scalar CurvatureJul 23 2007Given a surface in an asymptotically flat 3-manifold with nonnegative scalar curvature, we derive an upper bound for the capacity of the surface in terms of the area of the surface and the Willmore functional of the surface. The capacity of a surface ... More
Dual condensates at finite isospin chemical potentialJul 26 2015The dual observables as order parameters for center symmetry are tested at finite isospin chemical potential $\mu_I$ in a Polyakov-loop enhanced chiral model of QCD with physical quark masses. As a counterpart of the dressed Polyakov-loop, the first Fourier ... More
The Measure for the Multiverse and the Probability for InflationApr 09 2007We investigate the measure problem in the framework of inflationary cosmology. The measure of the history space is constructed and applied to inflation models. Using this measure, it is shown that the probability for the generalized single field slow ... More
Quantum UV/IR Relations and Holographic Dark Energy from Entropic ForceJan 25 2010Mar 30 2010We investigate the implications of the entropic force formalism proposed by Verlinde. We show that an UV/IR relation proposed by Cohen et al, as well as an uncertainty principle proposed by Hogan can be derived from the entropic force formalism. We show ... More
Multi-Stream InflationMar 12 2009Jul 24 2009We propose a "multi-stream" inflation model, which is a double field model with spontaneous breaking and restoration of an approximate symmetry. We calculate the density perturbation and non-Gaussianity in this model. We find that this model can have ... More
M2-branes Coupled to Antisymmetric FluxesMay 22 2008Jul 21 2008By turning on antisymmetric background fluxes, we study how multiple M2-branes are coupled to them. Our investigation concentrates on the gauge invariance conditions for the Myers-Chern-Simons action. Furthermore, the dimensional reduction of M2-branes ... More
Typicality, Freak Observers and the Anthropic Principle of ExistenceAug 30 2007We propose an alternative anthropic probability for calculating the probabilities in eternal inflation. This anthropic probability follows naturally from the weak anthropic principle, and does not suffer the freak observer or the typicality problems. ... More
Einstein Equations From Holographic Thermodynamics and Holographic EntropyJul 03 2012Jul 08 2012We derive the Einstein field equations and black hole entropy from the first law of thermodynamics on a holographic time-like screen. Because of the universality of gravity, the stress tensor on the screen must be independent of the details of matter ... More
f(R) Gravity and Maxwell Equations from the Holographic PrincipleFeb 06 2011Feb 21 2011Extending the holographic program of [1], we derive f(R) gravity and the Maxwell equations from the holographic principle, using time-like holographic screen. We find that to derive the Einstein equations and f(R) gravity in a natural holographic approach, ... More
A New Entropic Force Scenario and Holographic ThermodynamicsNov 15 2010Nov 25 2010We propose a new holographic program of gravity in which we introduce a surface stress tensor. Our proposal differs from Verlinde's in several aspects. First, we use an open or a closed screen, a temperature is not necessary but a surface energy density ... More
Casimir Energy, Holographic Dark Energy and Electromagnetic Metamaterial Mimicking de SitterOct 18 2009May 13 2010We compute the Casimir energy of the photon field in a de Sitter space and find it to be proportional to the size of the horizon, the same form of the holographic dark energy. We suggest to make metamaterials to mimic de Sitter space in laboratory and ... More
Transformation optics that mimics the system outside a Schwarzschild black holeDec 24 2009Dec 31 2009We applied the transformation optics to mimic a black hole of Schwarzschild form. Similar properties of photon sphere were also found numerically for the metamaterial black hole. Several reduced versions of the black hole systems were proposed for easier ... More
Scattering of particles by deformed non-rotating black holesAug 03 2015We study the excitation of axial quasi-normal modes of deformed non-rotating black holes by test-particles and we compare the associated gravitational wave signal with that expected in general relativity from a Schwarzschild black hole. Deviations from ... More
Axino dark matter in light of an anomalous X-ray lineMar 26 2014May 30 2014Axino as the superpartner of axion that solves the strong CP problem can be a good candidate of dark matter. Inspired by the 3.5 keV X-ray line signal found to be originated from galaxy clusters and Andromeda galaxy, we study axino models with R-parity ... More