arXiv subjects

Yi-Shi Duan

Publications and source records attributed to Yi-Shi Duan.

At least 55 records · Page 3Linked to original sources

arXiv2007

Vortices in Quantum Röntgen Effect

By the application of $ϕ$-mapping topological theory, the properties of vortices in quantum Röntgen effect is thoroughly studied. The explicit expression of the vorticity is obtained, wherein which the $δ$ function indicates that the vortices can only stem from the zero points of $ϕ$ and the magnetic flux of the consequent monopoles is quantized in terms of the Hopf indices and Brouwer degrees. The evolution of vortex lines is discussed. The reduced dynamic equation and a conserved dynamic quantity on stable vortex lines are obtained.

cond-mat.other↗

arXiv2007

Topological Properties of Phase Singularities in Wave Fields

Phase singularities as topological objects of wave fields appear in a variety of physical, chemical, and biological scenarios. In this paper, by making use of the $ϕ$-mapping topological current theory, we study the topological properties of the phase singularities in two and three dimensional space in details. The topological inner structure of the phase singularities are obtained, and the topological charge of the phase singularities are expressed by the topological numbers: Hopf indices and Brouwer degrees. Furthermore, the topological invariant of the closed and knotted phase singularities in three dimensional space are also discussed in details.

physics.geo-ph↗

arXiv2007

Fermion Absorption Cross Section and Topology of Spherically Symmetric Black Holes

In 1997, Liberati and Pollifrone in Phys. Rev. D56 (1997) 6458 (hep-th/9708014) achieved a new formulation of the Bekenstein-Hawking formula, where the entropy and the Euler characteristic are related by $S=χA/8$. In this work we present a relation between the low-energy absorption cross section for minimally coupled fermions and the Euler characteristic of (3+1)-dimensional spherically symmetric black holes, i.e. $σ=χg_h^{-1}A$. Based on the relation, using the Gauss--Bonnet--Chern theorem and the $ϕ$-mapping method, an absorption cross section density is introduced to describe the topology of the absorption cross section. It is shown that the absorption cross section and its density are determined by the singularities of the timelike Killing vector field of the spacetime and these singularities carry the topological numbers, Hopf indices and Brouwer degrees, naturally.

hep-th↗

arXiv2007

Topological Vortex Lines in Two-Gap Superconductor

Based on the U(1) gauge potential decomposition theory and the $ϕ$-mapping method, we study the vortex lines in two-gap superconductor and obtain the condition, under which the vortices can carry an arbitrary fraction of magnetic flux. It has been pointed out that the Chern-Simon action is a topological invariant, which is just the total sum of all the self-linking numbers and all the linking numbers of the knot family.

cond-mat.supr-con↗

arXiv2007

Topological Excitation in Skyrme Theory

Based on the $ϕ$-mapping topological current theory and the decomposition of gauge potential theory, we investigate knotted vortex lines and monopoles in Skyrme theory and simply discuss the branch processes (splitting, merging and intersection) during the evolution of the monopoles.

hep-th↗

arXiv2007

Knotted Solitons in a Charged Two-Condensate Bose System

By making use of the decomposition of U(1) gauge potential theory and the ϕmapping method, we propose that a charged two-condensate Bose system possesses vortex lines and two classes of knotted solitons. The topological charges of the vortex lines are characterized by the Hopf indices and the Brower degrees of ϕ-mapping, and the knotted solitons are described by the nontrivial Hopf invariant and the BF action, respectively.

cond-mat.supr-con↗

arXiv2007

Novel Topological Invariant in the U(1) Gauge Field Theory

Based on the decomposition of U(1) gauge potential theory and the $ϕ$-mapping topological current theory, the three-dimensional knot invariant and a four-dimensional new topological invariant are discussed in the U(1) gauge field.

hep-th↗

arXiv2007

Topological aspect of black hole with Skyrme hair

Based on the $ϕ$-mapping topological current theory, we show that the presence of the black hole leaves fractional baryon charge outside the horizon in the Einstein-Skyrme theory. A topological current is derived from the Einstein-Skyrme system, which corresponds to the monopoles around the black hole. The branch process (splitting, merging and intersection) is simply discussed during the evolution of the monopoles.

hep-th↗

arXiv2007

Angular Momentum Conservation Law for Randall-Sundrum Models

In Randall-Sundrum models, by the use of general Noether theorem, the covariant angular momentum conservation law is obtained with the respect to the local Lorentz transformations. The angular momentum current has also superpotential and is therefore identically conserved. The space-like components $J_{ij}$ of the angular momentum for Randall-Sundrum models are zero. But the component $J_{04}$ is infinite.

gr-qc↗

arXiv2006

Fermionic zero modes in gauge and gravity backgrounds On $T^2$

In this note we study fermionic zero modes in gauge and gravity backgrounds taking a two dimensional compact manifold $T^2$ as extra dimensions. The result is that there exist massless Dirac fermions which have normalizable zero modes under quite general assumptions about these backgrounds on the bulk. Several special cases of gauge background on the torus are discussed and some simple fermionic zero modes are obtained.

hep-th↗

arXiv2005

Corrections to the Nonrelativistic Ground Energy of a Helium Atom

Considering the nuclear motion, the authors give out the nonrelativistic ground energy of a helium atom by using a simple but effective variational wave function with a flexible parameter $k$. Based on this result, the relativistic and radiative corrections to the nonrelativistic Hamiltonian are discussed. The high precision value of the helium ground energy is evaluated to be -2.90338 a.u., and the relative error is 0.00034%.

quant-ph↗

arXiv2005

A new form of self-duality equations with topological term

Based on the U(1) gauge potential decomposition theory and $ϕ$-mapping theory, the topological inner structure of the self-duality (Bogomol'nyi-type) equations are studied. The special form of the gauge potential decomposition is obtained directly from the first of the self-duality equations. Using this decomposition, the topological inner structure of the Chern-Simons-Higgs (CSH) vortex is discussed. Furthermore, we obtain a rigorous self-dual equation with topological term for the first time, in which the topological term has been ignored by other physicists.

hep-th↗

arXiv2005

Spinor Field Realizations of Non-critical $W_{2,s}$ Strings

In this paper, we construct the nilpotent Becchi-Rouet-Stora-Tyutin($BRST$) charges of spinor non-critical $W_{2,s}$ strings. The cases of $s=3,4$ are discussed in detail, and spinor realization for $s=4$ is given explicitly. The $BRST$ charges are graded.

hep-th↗

arXiv2005

Fermionic zero modes in self-dual vortex background

We study fermionic zero modes in the background of self-dual vortex on a two-dimensional non-compact extra space in 5+1 dimensions. In the Abelian Higgs model, we present an unified description of the topological and non-topological self-dual vortex on the extra two dimensions. Based on it, we study localization of bulk fermions on a brane with inclusion of Yang-Mills and gravity backgrounds in six dimensions. Through two simple cases, it is shown that the vortex background contributes a phase shift to the fermionic zero mode, this phase is actually origin from the Aharonov-Bohm effect.

hep-th↗

arXiv2005

The Non-Abelian Topological Gauge Field Theory of \tilde{p}-Branes

By the generalization of Chern--Simons topological current and Gauss--Bonnet-Chern theorem, the purpose of this paper is to make a non-Abelian gauge field theory foundation of the topological current of $\tilde{p}$-branes formulated in our previous work. Using $ϕ$--mapping topological current theory proposed by Professor Duan, we find that the topological $\tilde p$-branes are created at every isolated zero of vector field $\vec ϕ(x)$. It is shown that the topological charges carried by $\tilde p$-branes are topologically quantized and labeled by Hopf index and Brouwer degree, i.e., the winding number of the $ϕ$--mapping. The action of topological $\tilde p$--branes is obtained and is just Nambu action for multistrings when $D- \tilde d=2$.

hep-th↗

arXiv2003

Cosmic Strings and Quintessence

We present a new Lorentz gauge invariant U(1) topological field theory in Riemann-Cartan spacetime manifold $U_{4}$. By virtue of the decomposition theory of U(1) gauge potential and the $ ϕ$--mapping topological current theory, it is proved that the U(1) complex scalar field $ϕ(x)$ can be looked upon as the order parameter field in our Universe, and the set of zero points of $ϕ(x)$ create the cosmic strings as the spacetime defects in the early Universe. In the standard cosmology this complex scalar order parameter field possesses negative pressure, provides an accelerating expansion of Universe and be able to explain the inflation in the early Universe. Therefore this complex scalar field is not only the order parameter field created the cosmic strings, but also reasonably behaves as the quintessence, the dark energy.

hep-th↗

arXiv2002

The configuration of a topological current and physical structure: an application and paradigmatic evidence

In the $ϕ$-mapping theory, the topological current constructed by the order parameters can possess different inner structure. The difference in topology must correspond to the difference in physical structure. The transition between different structures happens at the bifurcation point of the topological current. In a self-interaction two-level system, the change of topological particles corresponds to change of energy levels.

physics.gen-ph↗

arXiv2001

Evolution of the Chern-Simons Vortices

Based on the gauge potential decomposition theory and the $ϕ$-mapping theory, the topological inner structure of the Chern-Simons-Higgs vortex has been showed in detail. The evolution of CSH vortices is studied from the topological properties of the Higgs scalar field. The vortices are found generating or annihilating at the limit points and encountering, splitting or merging at the bifurcation points of the scalar field $ϕ.$

hep-th↗