arXiv subjects

Han-Ying Guo

Publications and source records attributed to Han-Ying Guo.

52 records · Page 3Linked to original sources

arXiv2001

Variations in Discrete Mechanics and Field Theory

Some problems on variations are raised for classical discrete mechanics and field theory and the difference variational approach with variable step-length is proposed motivated by Lee's approach to discrete mechanics and the difference discrete variational principle for difference discrete mechanics and field theory on regular lattice. Based upon Hamilton's principle for the vertical variations and double operation of vertical exterior differential on action, it is shown that for both continuous and variable step-length difference cases there exists the nontrivial Euler-Lagrange cohomology as well as the necessary and sufficient condition for symplectic/multi-symplectic structure preserving properties is the relevant Euler-Lagrange 1-form is closed in both continuous and difference classical mechanics and field theory. While the horizontal variations give rise to the relevant identities or relations of the Euler-Lagrange equation and conservation law of the energy/energy-momentum tensor for continuous or discrete systems. The total variations are also discussed. Especially, for those discrete cases the variable step-length of the difference is determined by the relation between the Euler-Lagrange equation and conservation law of the energy/energy-momentum tensor. In addition, this approach together with difference version of the Euler-Lagrange cohomology can be applied not only to discrete Lagrangian formalism but also to the Hamiltonian formalism for difference mechanics and field theory.

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arXiv2001

Total Variation in Hamiltonian Formalism and Symplectic-Energy integrators

We present a discrete total variation calculus in Hamiltonian formalism in this paper. Using this discrete variation calculus and generating functions for the flows of Hamiltonian systems, we derive two-step symplectic-energy integrators of any finite order for Hamiltonian systems from a variational perspective. The relationship between symplectic integrators derived directly from the Hamiltonian systems and the variationally derived symplectic-energy integrators is explored.

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arXiv2001

Total Variation and Variational Symplectic-Energy-Momentum integrators

A discrete total variation calculus with variable time steps is presented in this letter. Using this discrete variation calculus, we generalize Lee's discrete mechanics and derive variational symplectic-energy-momentum integrators by Kane, Marsden and Ortiz. The relationship among discrete total variation, Lee's discrete mechanics and Kane-Marsden-Ortiz's integrators is explored.

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arXiv2001

On Symplectic, Multisymplectic Structures-Preserving in Simple Finite Element Method

By the simple finite element method, we study the symplectic, multisymplectic structures and relevant preserving properties in some semi-linear elliptic boundary value problem in one-dimensional and two-dimensional spaces respectively. We find that with uniform mesh, the numerical schemes derived from finite element method can keep a preserved symplectic structure in one-dimensional case and a preserved multisymplectic structure in two-dimentional case respectively. These results are in fact the intrinsic reason that the numerical experiments indicate that such finite element schemes are accurate in practice.

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arXiv2001

A Note on Symplectic, Multisymplectic Scheme in Finite Element Method

We find that with uniform mesh, the numerical schemes derived from finite element method can keep a preserved symplectic structure in one-dimensional case and a preserved multisymplectic structure in two-dimentional case in certain discrete version respectively. These results are in fact the intrinsic reason that the numerical experiments indicate that such finite element algorithms are accurate in practice.

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arXiv2000

Global geometric properties of AdS space and the AdS/CFT correspondence

The Poisson kernels and relations between them for a massive scalar field in a unit ball $B^n$ with Hua's metric and conformal flat metric are obtained by describing the $B^n$ as a submanifold of an $(n+1)$-dimensional embedding space. Global geometric properties of the AdS space are discussed. We show that the $(n+1)$-dimensional AdS space AdS$_{n+1}$ is isomorphic to $RP^1\times B^n$ and boundary of the AdS is isomorphic to $RP^1\times S^{n-1}$. Bulk-boundary propagator and the AdS/CFT like correspondence are demonstrated based on these global geometric properties of the $RP^1\times B^n$.

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arXiv1999

Symmetry Realization, Poisson Kernel and the AdS/CFT Correspondence

Two kinds of realizations of symmetry on classical domains or the Euclidean version of AdS space are used to study AdS/CFT correspondence. Mass of free particles is defined as an AdS group invariant, the Klein-Gordon and Dirac equations for relativistic particles in the AdS space are set up as a mimic in the case of Minkowskian space. The bulk-boundary propagator on the AdS space is given by the Poisson kernel. Theorems on the Poisson kernel guarantee the existence and sole of the bulk-boundary propagator. The propagator is used to calculate correlators of the theories that live on the boundary of the AdS space and show conformal invariance, which is desired by the AdS/CFT correspondence.

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arXiv1998

On Torsion and Nieh-Yan Form

Using the well-known Chern-Weil formula and its generalization, we systematically construct the Chern-Simons forms and their generalization induced by torsion as well as the Nieh-Yan (N-Y) forms. We also give an argument on the vanishing of integration of N-Y form on any compact manifold without boundary. A systematic construction of N-Y forms in D=4n dimension is also given.

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arXiv1998

Quantization of Chern-Simons Coefficient

The relation between the Dirac quantization condition of magnetic charge and the quantization of the Chern-Simons coefficient is obtained. It implies that in a (2+1)-dimensional QED with the Chern-Simons topological mass term and the existence of a magnetic monopole with magnetic charge $g$, the Chern-Simons coefficient must be also quantized, just as in the non-Abelian case.

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arXiv1998

Two Particle Physics Models With Spontaneous CP Violation From Gauge Theory On Discrete Group

Based on the differential calculus and the gauge theory on discrete groups, we reconstruct two physics models with spontaneous CP violation: (1) The Georgi-Glashow-Lee model with two Higgs triplets; (2) The Weinberg-Salam-Branco model with three Higgs doublets and the natural flavor conservation (NFC). We focus on the Lagrangian terms containing the Higgs particles and show that with an appropriate choice of the discrete groups, we can obtain the physically meaningful Yukawa couplings and the Higgs potentials which lead to the spontaneous CP violation consequently.

hep-ph↗

arXiv1995

Intrinsic Regularization Method in QCD

There exist certain intrinsic relations between the ultraviolet divergent graphs and the convergent ones at the same loop order in renormalizable quantum field theories. Whereupon we may establish a new method, the intrinsic regularization method, to regularize those divergent graphs. In this paper, we apply this method to QCD at the one loop order. It turns out to be satisfactory:The gauge invariance is preserved manifestly and the results are the same as those derived by means of other regularization methods.

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arXiv1994

On inserter regularization method

There exist certain intrinsic relations between the ultraviolet divergent graphs and the convergent ones at the same loop order in renormalizable quantum field theories. Whereupon we present a new method, the inserter regularization method, to regulate those divergent graphs. In this letter, we demonstrate this method with the $ϕ^4$ theory and QED at the one loop order. Some applications to SUSY-models are also made at the one loop order, which shows that supersymmetry is preserved manifestly and consistently.

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arXiv1994

A Note On Intrinsic Regularization Method

There exist certain intrinsic relations between the ultraviolet divergent graphs and the convergent ones at the same loop order in renormalizable quantum field theories. Whereupon we may establish a new method, the intrinsic regularization method, to regulate those divergent graphs. In this note, we present a proposal, the inserter proposal, to the method. The $ϕ^4$ theory and QED at the one loop order are dealt with in some detail. Inserters in the standard model are given. Some applications to SUSY-models are also made at the one loop order.

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arXiv1994

A Gauge Field Model On $SU(2)_L\times SU(2)_R\times U(1)_Y \times π_4(G_{YM})$

We reconstruct the Lagrangian of a left-right symmetric model with the gauge group $SU(2)_L\times SU(2)_R\times U(1)_Y \times π_4(SU(2)_L\times SU(2)_R\times U(1)_Y) $. The Higgs fields appear as gauge fields on discrete gauge group $π_4(SU(2)_L\times SU(2)_R\times U(1)_Y) $ and are assigned in a way complying with the principle that both the original gauge group $G_{YM}$ and the discrete group $π_4(G_{YM})$ should be taken as gauge groups in sense of non-commutative geometry.

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arXiv1994

A Gauge Field Model On $SU(2)_L\times SU(2)_R\times U(1)_Y \times π_4(G_{YM})$

We construct a gauge field model based on $SU(2)_L\times SU(2)_R\times U(1)_Y \times π_4(SU(2)_L\times SU(2)_R\times U(1)_Y) $ from the principle that both the original gauge group $G_{YM}$ and the discrete group $π_4(G_{YM})$ should be taken as gauge groups in the sense of non-commutative geometry. We show that the Yukawa coupling and the Higgs mechanism appear as natural results.

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arXiv1992

Intrinsic Vertex Regularization and Renormalization in $ϕ^4$ Field Theory

Based upon the intrinsic relation between the divergent lower point functions and the convergent higher point ones in the renormalizable quantum field theories, we propose a new method for regularization and renormalization in QFT. As an example, we renormalize the $ϕ^{4}$ theory at the one loop order by means of this method.

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