2,359 research outputs found
Spinor Decomposition of SU(2) Gauge Potential and The Spinor Structures of Chern-Simons and Chern Density
In this paper, the decomposition of SU(2) gauge potential in terms of Pauli
spinors is studied. Using this decomposition, the spinor strutures of the
Chern-Simons form and the Chern density are obtained. Furthermore, by these
spinor structures, the knot quantum number of non-Abelian gauge theory is
discussed, and the second Chern number is characterized by the Hopf indices and
the Brouwer degrees of -mapping.Comment: 11 page
Type-II quadrupole topological insulators
Modern theory of electric polarization is formulated by the Berry phase,
which, when quantized, leads to topological phases of matter. Such a
formulation has recently been extended to higher electric multipole moments,
through the discovery of the so-called quadupole topological insulator. It has
been established by a classical electromagnetic theory that in a
two-dimensional material the quantized properties for the quadupole topological
insulator should satisfy a basic relation. Here we discover a new type of
quadrupole topological insulator (dubbed type-II) that violates this relation
due to the breakdown of the correspondence that a Wannier band and an edge
energy spectrum close their gaps simultaneously. We find that, similar to the
previously discovered (referred to as type-I) quadrupole topological insulator,
the type-II hosts topologically protected corner states carrying fractional
corner charges. However, the edge polarizations only occur at a pair of
boundaries in the type-II insulating phase, leading to the violation of the
classical constraint. We demonstrate that such new topological phenomena can
appear from quench dynamics in non-equilibrium systems, which can be
experimentally observed in ultracold atomic gases. We also propose an
experimental scheme with electric circuits to realize such a new topological
phase of matter. The existence of the new topological insulating phase means
that new multipole topological insulators with distinct properties can exist in
broader contexts beyond classical constraints.Comment: 32 pages, 17 figure
GEOCHEMICAL CHARACTERISTICS OF TIANMENSHAN COMPOSITE PLUTON, SOUTH CHINA
The southern Jiangxi province is located at east Nanling range, which is an important W-Sn metallogenic province of China. The Early Yanshanian Tianmenshan is composed of the main-phase porphyritic biotite granite and the highly differentiated fine-gained biotite granite, intruding in the Lower Cambrian Niujiaohe Formation. The main-phase granite and the late-stage highly differentiated granite emplaced at 152–158 Ma and 152–151 Ma, respectively. The later was in the center of the pluton as a ovalize shape, with a transitional contact with the main-phase granite.The southern Jiangxi province is located at east Nanling range, which is an important W-Sn metallogenic province of China. The Early Yanshanian Tianmenshan is composed of the main-phase porphyritic biotite granite and the highly differentiated fine-gained biotite granite, intruding in the Lower Cambrian Niujiaohe Formation. The main-phase granite and the late-stage highly differentiated granite emplaced at 152–158 Ma and 152–151 Ma, respectively. The later was in the center of the pluton as a ovalize shape, with a transitional contact with the main-phase granite
Topological Zero-Thickness Cosmic Strings
In this paper, based on the gauge potential decomposition and the
mapping theories, we study the topological structures and properties of
the cosmic strings that arise in the Abelian-Higgs gauge theory in the
zero-thickness limit. After a detailed discussion, we conclude that the
topological tensor current introduced in our model is a better and more basic
starting point than the generally used Nambu-Goto effective action for studying
cosmic strings.Comment: 10 pages, no figure
Optimizing production scheduling of steel plate hot rolling for economic load dispatch under time-of-use electricity pricing
Time-of-Use (TOU) electricity pricing provides an opportunity for industrial
users to cut electricity costs. Although many methods for Economic Load
Dispatch (ELD) under TOU pricing in continuous industrial processing have been
proposed, there are still difficulties in batch-type processing since power
load units are not directly adjustable and nonlinearly depend on production
planning and scheduling. In this paper, for hot rolling, a typical batch-type
and energy intensive process in steel industry, a production scheduling
optimization model for ELD is proposed under TOU pricing, in which the
objective is to minimize electricity costs while considering penalties caused
by jumps between adjacent slabs. A NSGA-II based multi-objective production
scheduling algorithm is developed to obtain Pareto-optimal solutions, and then
TOPSIS based multi-criteria decision-making is performed to recommend an
optimal solution to facilitate filed operation. Experimental results and
analyses show that the proposed method cuts electricity costs in production,
especially in case of allowance for penalty score increase in a certain range.
Further analyses show that the proposed method has effect on peak load
regulation of power grid.Comment: 13 pages, 6 figures, 4 table
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