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1.
In the Higgs phase we may be left with a residual finite symmetry groupH of the condensate. The topological interactions between the magnetic and electric excitations in these so-called discreteH gauge theories are completely described by the Hopf algebra or quantum groupD(H). In 2+1 dimensional space time we may add a Chern-Simons term to such a model. This deforms the underlying Hopf algebraD(H) into the quasi-Hopf algebraD (H) by means of a 3-cocycle onH. Consequently, the finite number of physically inequivalent discreteH gauge theories obtained in this way are labelled by the elements of the cohomology groupH 3(H,U(1)). We briefly review the above results in these notes. Special attention is given to the Coulomb screening mechanism operational in the Higgs phase. This mechanism screens the Coulomb interactions, but not the Aharonov-Bohm interactions.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 98. No. 3, pp. 509–523, March, 1994  相似文献   
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We derive some general results for Killing vectors on arbitrary coset manifolds and explicitly exhibit the squashed seven-sphere as the coset space Sp4×Sp2/Sp2×Sp2. Using these results, we then analyze the zero-mass sector of supergravity of the squashed S7 and argue that it is not interpretable as a spontaneously broken version of N=8 supergravity. We also point out the existence of a new solution which combines squashing and torsion.  相似文献   
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In non-abelian gauge theories with a non-real fermion content it is possible that vector channels become more attractive than the most attractive scalar channel. It is speculated that the appearance of a vector condensate may signal the presence of massless composite vector fields which gauge a flavour symmetry of the underlying model, as is suggested by earlier work on non-linear spinor models.  相似文献   
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Shah  Syed Aamir Ali  Bais  Abdul  Zhang  Lei 《Nonlinear dynamics》2020,99(4):3231-3251
Nonlinear Dynamics - The chaotic nature of the brain can be observed by electroencephalogram signals. This chaotic behavior can be affected by the progressive nature of neurodegenerative disorders...  相似文献   
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In this paper we consider configurations of monopoles with multiple magnetic charge in nonabelian gauge theory. Explicit gauge transformations are constructed which eliminate the string singularities for single monopoles of multiple magnetic charge, and for an arbitrary number of monopoles lying along a line. The question of finding nonsingular solutions is discussed.  相似文献   
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The assessment model for ultraviolet radiation and risk “AMOUR” is applied to output from two chemistry‐climate models (CCMs). Results from the UK Chemistry and Aerosols CCM are used to quantify the worldwide skin cancer risk avoided by the Montreal Protocol and its amendments: by the year 2030, two million cases of skin cancer have been prevented yearly, which is 14% fewer skin cancer cases per year. In the “World Avoided,” excess skin cancer incidence will continue to grow dramatically after 2030. Results from the CCM E39C‐A are used to estimate skin cancer risk that had already been inevitably committed once ozone depletion was recognized: excess incidence will peak mid 21st century and then recover or even super‐recover at the end of the century. When compared with a “No Depletion” scenario, with ozone undepleted and cloud characteristics as in the 1960s throughout, excess incidence (extra yearly cases skin cancer per million people) of the “Full Compliance with Montreal Protocol” scenario is in the ranges: New Zealand: 100–150, Congo: ?10–0, Patagonia: 20–50, Western Europe: 30–40, China: 90–120, South‐West USA: 80–110, Mediterranean: 90–100 and North‐East Australia: 170–200. This is up to 4% of total local incidence in the Full Compliance scenario in the peak year.  相似文献   
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An extensive and detailed analysis of self-dual gauge fields, in particular with axial symmetry, is presented, culminating in a purely algebraic procedure to generate solutions. The method which is particularly suited for the construction of multimonopole solutions for a theory with arbitrary G, is also applicable to a wide class of non-linear sigma models.The relevant symmetries as well as the associated linear problems which underly the exact solubility of the problem, are constructed and discussed in detail.  相似文献   
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