166 research outputs found

    Orbifold instantons, moment maps, and Yang-Mills theory with sources

    Get PDF
    We revisit the problem of constructing instantons on ADE orbifolds R4/Γ and point out some subtle relations with the complex structure on the orbifold. We consider generalized instanton equations on R4/Γ which are BPS equations for the Yang-Mills equations with an external current. The relation between level sets of the moment maps in the hyper-Kähler quotient construction of the instanton moduli space and sources in the Yang-Mills equations is discussed. We describe two types of spherically symmetric Γ-equivariant connections on complex V bundles over R4/Γ which are tailored to the way in which the orbifold group acts on the fibers. Some explicit Abelian and non-Abelian SU(2)-invariant solutions to the instanton equations on the orbifold are worked out. © 2013 American Physical Society

    Instantons and Yang-Mills Flows on Coset Spaces

    Full text link
    We consider the Yang-Mills flow equations on a reductive coset space G/H and the Yang-Mills equations on the manifold R x G/H. On nonsymmetric coset spaces G/H one can introduce geometric fluxes identified with the torsion of the spin connection. The condition of G-equivariance imposed on the gauge fields reduces the Yang-Mills equations to phi^4-kink equations on R. Depending on the boundary conditions and torsion, we obtain solutions to the Yang-Mills equations describing instantons, chains of instanton-anti-instanton pairs or modifications of gauge bundles. For Lorentzian signature on R x G/H, dyon-type configurations are constructed as well. We also present explicit solutions to the Yang-Mills flow equations and compare them with the Yang-Mills solutions on R x G/H.Comment: 1+12 page

    Non-Abelian Vortices, Super-Yang-Mills Theory and Spin(7)-Instantons

    Full text link
    We consider a complex vector bundle E endowed with a connection A over the eight-dimensional manifold R^2 x G/H, where G/H = SU(3)/U(1)xU(1) is a homogeneous space provided with a never integrable almost complex structure and a family of SU(3)-structures. We establish an equivalence between G-invariant solutions A of the Spin(7)-instanton equations on R^2 x G/H and general solutions of non-Abelian coupled vortex equations on R^2. These vortices are BPS solitons in a d=4 gauge theory obtained from N=1 supersymmetric Yang-Mills theory in ten dimensions compactified on the coset space G/H with an SU(3)-structure. The novelty of the obtained vortex equations lies in the fact that Higgs fields, defining morphisms of vector bundles over R^2, are not holomorphic in the generic case. Finally, we introduce BPS vortex equations in N=4 super Yang-Mills theory and show that they have the same feature.Comment: 14 pages; v2: typos fixed, published versio

    Hidden Symmetries and Integrable Hierarchy of the N=4 Supersymmetric Yang-Mills Equations

    Get PDF
    We describe an infinite-dimensional algebra of hidden symmetries of N=4 supersymmetric Yang-Mills (SYM) theory. Our derivation is based on a generalization of the supertwistor correspondence. Using the latter, we construct an infinite sequence of flows on the solution space of the N=4 SYM equations. The dependence of the SYM fields on the parameters along the flows can be recovered by solving the equations of the hierarchy. We embed the N=4 SYM equations in the infinite system of the hierarchy equations and show that this SYM hierarchy is associated with an infinite set of graded symmetries recursively generated from supertranslations. Presumably, the existence of such nonlocal symmetries underlies the observed integrable structures in quantum N=4 SYM theory.Comment: 24 page

    Некоторые моменты сопоставительного анализа фонетики русского и туркменского языков

    Get PDF
    The comparison of some phonetic aspects of Russian and Turkmen languages has been given in this article.В статье дается сопоставление некоторых аспектов фонетического строя русского и туркменского языков

    К вопросу о роли гласных и согласных в звуковых традициях русского и туркменского языков

    Get PDF
    The analysis of vowel’s and consonant’s part at Russian and Turkmen languages has been given in this article.В статье дается анализ роли гласных и согласных звуков в русском и туркменском языках

    К вопросу о соответствии видов русских приставочных глаголов туркменским эквивалентам

    Get PDF
    Russian prefix verbs and their equivalents in the Turkmen language are examined in the article. The analysis of some aspects of the subject matter understudy is givenВ статье дается сопоставительный анализ глаголов совершенного и несовершенного видов русского и туркменского языков

    Про створення навчального посібника з граматики для студентів-медиків 1 курсу

    Get PDF
    Basic components of the grammar schoolbook’s models have been considered in this article. Methodic basis of this aspect training organization has been given. System of exercises and tasks in forming linguistic competence of the 1-st year medical students has been also described.У статті розглядаються основні складові моделі навчального посібника з граматики, дається методичне обґрунтування організації навчання даному аспекту, описується система завдань та вправ з формування мовної компетенції студентів-медиків першого курсу

    Anticancer substances of mushroom origin

    No full text
    The present status of investigations about the anticancer activity which is inherent to medicinal mushrooms, as well as their biomedical potential and future prospects are discussed. Mushroom products and extracts possess promising immunomodulating and anticancer effects, so the main biologically active substances of mushrooms responsible for immunomodulation and direct cytoto­xicity toward cancer cell lines (including rarely mentioned groups of anticancer mushroom proteins), and the mechanisms of their antitumor action were analyzed. The existing to date clinical trials of mushroom substances are mentioned. Mushroom anticancer extracts, obtained by the different solvents, are outlined. Modern approaches of cancer treatment with implication of mushroom products, including DNA vaccinotherapy with mushroom immunomodulatory adjuvants, creation of prodrugs with mushroom lectins that can recognize glycoconjugates on the cancer cell surface, development of nanovectors etc. are discussed. The future prospects of mushroom anticancer substances application, including chemical modification of polysaccharides and terpenoids, gene engineering of proteins, and implementation of vaccines are reviewed. Key Words: mushrooms, anticancer substances, extracts, vaccinotherapy
    corecore