Fractional Quantum Hall Effect and (2 + 1)-Dimensional Quantum Electrodynamics

By investigating the gap equation defining thefull electron propagator in the framework of (2 +1)-dimensional quantum electrodynamics, we derive thefractional quantum Hall effect at the filling factors = 1/2, 1/3, 2/5, 1/9. In particular, thevalue = 1/2 emerges as the lowest order of thedevelopment of this gap equation.     

Statistical Mechanical Theory of a Closed Oscillating Universe

Based on Newton’s laws reformulated in the Hamiltonian dynamics combined with statistical mechanics, we formulate a statistical mechanical theory supporting the hypothesis of a closed universe oscillating in phase-space. We find that the behavior of this universe as a whole can be represented by a free entropic oscillator whose lifespan is nonhomogeneous, thus implying that time is shorter or longer according to the state of this universe given through its entropy. We conclude that time reduces to the entropy production of this universe and that a nonzero entropy production means that local fluctuations could exist giving rise to the appearance of masses and to the curvature of the space.     

Letter: Constraint Propagation in (N + 1)-Dimensional Space-Time

Higher dimensional space-time models provide us an alternative interpretation of nature, and give us different dynamical aspects than the traditional four-dimensional space-time models. Motivated by such recent interests, especially for future numerical research of higher-dimensional space-time, we study the dimensional dependence of constraint propagation behavior. The N+1 Arnowitt-Deser-Misner evolution equation has matter terms which depend on N, but the constraints and constraint propagation equations remain the same. This indicates that there would be problems with accuracy and stability when we directly apply the N+1 ADM formulation to numerical simulations as we have experienced in four-dimensional cases. However, we also conclude that previous efforts in re-formulating the Einstein equations can be applied if they are based on constraint propagation analysis.     

New Exact Solution of (N+1)-Dimensional Burgers System

In this letter, using a Bäcklund transformation and the new variable separation approach, we find a new general solution of the (N+1)-dimensional Burgers system. The form of the universal formula obtained from many (2+1)-dimensional system is extended.     

Decomposition for a 2+1-Dimensional Discrete Integrable Model

A 2＋1-dimensional discrete is presented, which is decomposed into a new integrable symplectic map and a class of finite-dimensional integrable Hamiltonian systems, with aid of the nonlineaxization of Lax pairs. The system is completely integrable in the Liouville sense.     

Exact Periodic-Wave Solutions for (2+1)-Dimensional Boussinesq Equation and (3+1)-Dimensional KP Equation

The (2 1)-dimensional Boussinesq equation and (3 1)-dimensional KP equation are studied by using the extended Jacobi elliptic-function method. The exact periodic-wave solutions for the two equations are obtained.     

Exact Periodic-Wave Solutions for （2＋1）-Dimensional Boussinesq Equation and（3＋1）-Dimensional KP Equation

The (2 1)-dimensional Boussinesq equation and (3 1)-dimensional KP equation are studied by using the extended Jacobi elliptic-function method. The exact periodic-wave solutions for the two equations are obtained.     

(n+1)-Dimensional Gravity Duals to Quantum Criticalities with Spontaneous Symmetry Breaking

We reexamine the charged AdS domain wall solution to the Einstein-Abelian-Higgs model proposed by Gubser et al. as holographic superconductors at quantum critical points and comment on their statement about the uniqueness of gravity solutions. We generalize their explorations from (3+1)-dimensions to arbitrary n+1Ds and find that the n+1≥qslant5D charged AdS domain walls are unstable against electric perturbations.     

(n+1)-Dimensional Gravity Duals to Quantum Criticalities with Spontaneous Symmetry Breaking

We reexamine the charged AdS domain wall solution to the Einstein–Abelian–Higgs model proposed by Gubser et al.as holographic superconductors at quantum critical points and comment on their statement about the uniqueness of gravity solutions.We generalize their explorations from(3+1)-dimensions to arbitrary n+1Ds and find that the n+1 5D charged AdS domain walls are unstable against electric perturbations.     

Integrable Deformations of the (2+1)-Dimensional Heisenberg Ferromagnetic Model

Based on the covariant prolongation structure technique,we construct the integrable higher-order deformations of the (2+1)-dimensional Heisenberg ferromagnet model and obtain their su(2)×R(λ) prolongation structures.By associating these deformed multidimensional Heisenberg ferromagnet models with the moving space curve in Euclidean space and using the Hasimoto function,we derive their geometrical equivalent counterparts,i.e.,higher-order (2+1)-dimensional nonlinear Schrödinger equations.     

An (n+1)-Dimensional Integrable Model: Painlevé Test

A (3+1)-dimensional model is proposed at first. The integrability of the model is proved by using the standard Painlevk analysis. Then the model is extended to (n + 1)-dimensional case. The model is space-isotropic and is a type of the modified KdV extension in higher dimensions.     

Variable Separation Solutions in (1+1)-Dimensional and (3+1)-Dimensional Systems via Entangled Mapping Approach

In this paper, the entangled mapping approach (EMA) is applied to obtain variable separation solutions of (1 1)-dimensional and (3 1)-dimensional systems. By analysis, we firstly find that there also exists a common formula to describe suitable physical fields or potentials for these (1 1)-dimensional models such as coupled integrable dispersionless (CID) and shallow water wave equations. Moreover, we find that the variable separation solution of the (3 1)-dimensional Burgers system satisfies the completely same form as the universal quantity U1 in (2 1 )-dimensional systems. The only difference is that the function q is a solution of a constraint equation and p is an arbitrary function of three independent variables.     

Multivortex Solutions in (2+1)-Dimensional Abelian Higgs Model with a Chern-Simons Term

The multivortex solutions of (2+l)-dimensional Abelian Higgs model with a Chern-Simons term are stlrrlied. The Bogomol'nyi-type equations and corresponding Weinberg's index theorem have been derived for a sixth-order Higgs potential. The magnetic field is different from that of the Abelian Chern-Simons Higgs model which has no Maxwell term, and has a maximum at the center of the vortex.     

New Exact Solutions for （1 ＋ 1）-Dimensional Dispersion-Less System

Using improved homogeneous balance method, we obtain complex function form new exact solutions for the （1＋1）-dimensional dispersion-less system, and from the exact solutions we derive real function form solution of the field u. Based on this real function form solution, we find some new interesting coherent structures by selecting arbitrary functions appropriately.     

Symmetries of a (2+1)-Dimensional Toda-like Lattice

Lie group technique for solving differential-difference equations is applied to a new (2 1)-dimensional Toda-like lattice. An infinite dimensional Lie algebra and the corresponding commutation relations are obtained.     

Symmetries of a （2＋1）-Dimensional Toda-like Lattice

Lie group technique for solving differential-difference equations is applied to a new (2 1)-dimensional Toda-like lattice. An infinite dimensional Lie algebra and the corresponding commutation relations are obtained.     

Interaction Solutions for (1+1)-Dimensional Higher-Order Broer-Kaup System

The (1+1)-dimensional higher-order Broer-Kaup (HBK) system is studied by consistent tanh expansion (CTE) method in this paper. It is proved that the HBK system is CTE solvable, and some exact interaction solutions among different nonlinear excitations such as solitons, rational waves, periodic waves, corresponding images are explicitly given.     

Letter: Quantum Mechanics Forbids Singularities in a Closed Radiation-dominated FRW Universe

The existence of singularities in a closed FRWuniverse depends on the assumption that generalrelativity is valid for distances less than the Plancklength. However, the stationary state wave functions of the Schrodinger equation for a closedradiation-dominated FRW universe derived by Elbaz et al.are zero at zero radius of curvature. Thus, even ifgeneral relativity is assumed valid at distances less than the Planck length, quantum mechanics seems to forbid singularities in a closed radiation-dominatedFRW universe.     

Entropy in (1 + 1)-Dimensional Black Hole

The Klein–Gordon equation and Diracequation are solved in the backgrounds of a (1 +1)-dimensional black hole with 'tHooft andquasiperiodic boundary conditions,respectively. The corresponding entropies of bosons and fermions arecalculated; the divergence in the fermionic entropy hasthe same form as that in the bosonic one, except thatthe coefficient is different.     

Oscillating Solitons for (2+1)-Dimensional Nonlinear Models

Using extended homogeneous balance method and variable separation hypothesis,we found new variableseparation solutions with three arbitrary functions of the (2 1)-dimensional dispersive long-wave equations.Based on derived solutions,we revealed abundant oscillating solitons such as dromion,multi-dromion,solitoff,solitary waves,and so on,by selecting appropriate functions.