1,069 research outputs found

    Quantum theory of non-abelian differential forms and link polynomials

    Get PDF
    A topological quantum field theory of non-abelian differential forms is investigated from the point of view of its possible applications to description of polynomial invariants of higher-dimensional two-component links. A path-integral representation of the partition function of the theory, which is a highly on-shell reducible system, is obtained in the framework of the antibracket-antifield formalism of Batalin and Vilkovisky. The quasi-monodromy matrix, giving rise to corresponding skein relations, is formally derived in a manifestly covariant non-perturbative manner.Comment: 18 pages, REVISED: minor improvement

    SU(2) and the Kauffman bracket

    Full text link
    A direct relationship between the (non-quantum) group SU(2) and the Kauffman bracket in the framework of Chern-Simons theory is explicitly shown.Comment: 5 page

    Three-dimensional topological quantum field theory of Witten type

    Get PDF
    Description of two three-dimensional topological quantum field theories of Witten type as twisted supersymmetric theories is presented. Low-energy effective action and a corresponding topological invariant of three-dimensional manifolds are considered

    Spin-selective localization due to intrinsic spin-orbit coupling

    Full text link
    We study spin-dependent diffusive transport in the presence of a tunable spin-orbit (SO) interaction in a two-dimensional electron system. The spin precession of an electron in the SO coupling field is expressed in terms of a covariant curvature, affecting the quantum interference between different electronic trajectories. Controlling this curvature field by modulating the SO coupling strength and its gradients by, e.g., electric or elastic means, opens intriguing possibilities for exploring spin-selective localization physics. In particular, applying a weak magnetic field allows the control of the electron localization independently for two spin directions, with the spin-quantization axis that could be "engineered" by appropriate SO interaction gradients.Comment: 7 pages, 1 figur

    "Microscopic" approach to the Ricci dark energy

    Full text link
    A derivation of the Ricci dark energy from quantum field theory of fluctuating "matter" fields in a classical gravitational background is presented. The coupling to the dark energy, the parameter 'a', is estimated in the framework of our formalism, and qualitatively it appears to be within observational expectations.Comment: 7 page

    Gauge-Invariant Formulation of Spin-Current-Density Functional Theory

    Get PDF
    Spin-currents and non-abelian gauge potentials in electronic systems can be treated by spin-current-density functional theory, whose main input is the exchange-correlation (xc) energy expressed as a functional of spin-currents. Constructing a functional of spin currents that is invariant under U(1)×\timesSU(2) transformations is a long-standing challenge. We solve the problem by expressing the energy as a functional of a new variable we call "invariant vorticity". As an illustration we construct the xc energy functional for a two-dimensional electron gas with linear spin-orbit coupling and show that it is proportional to the fourth power of the spin current.Comment: 8 pages, 3 figures, submitte

    β\beta Decay and Isomeric Properties of Neutron-Rich Ca and Sc Isotopes

    Full text link
    The isomeric and β\beta-decay properties of neutron-rich 5357^{53-57}Sc and 53,54^{53,54}Ca nuclei near neutron number NN=32 are reported, and the low-energy level schemes of 53,54,56^{53,54,56}Sc and 5357^{53-57}Ti are presented. The low-energy level structures of the 21_{21}Sc isotopes are discussed in terms of the coupling of the valence 1f7/21f_{7/2} proton to states in the corresponding 20_{20}Ca cores. Implications with respect to the robustness of the NN=32 subshell closure are discussed, as well as the repercussions for a possible NN=34 subshell closure.Comment: 17 pages, 17 figures, accepted to Phys. Rev.

    4-Dimensional BF Theory as a Topological Quantum Field Theory

    Full text link
    Starting from a Lie group G whose Lie algebra is equipped with an invariant nondegenerate symmetric bilinear form, we show that 4-dimensional BF theory with cosmological term gives rise to a TQFT satisfying a generalization of Atiyah's axioms to manifolds equipped with principal G-bundle. The case G = GL(4,R) is especially interesting because every 4-manifold is then naturally equipped with a principal G-bundle, namely its frame bundle. In this case, the partition function of a compact oriented 4-manifold is the exponential of its signature, and the resulting TQFT is isomorphic to that constructed by Crane and Yetter using a state sum model, or by Broda using a surgery presentation of 4-manifolds.Comment: 15 pages in LaTe
    corecore