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The scale invariant gravity theory coupled to conformally invariant matter is investigated. We show that in the non‐supersymmetric case the conformally coupled scalars belong to an manifold, while in the supersymmetric case the scalar manifold becomes isomorphic to the Kählerian space =. In both cases when the underlying scale symmetry is preserved the vacuum corresponds to de Sitter space. Once the scale symmetry is broken by quantum effects, a transition to flat space becomes possible. We argue that the scale violating terms are induced by anomalies related to a symmetry. The anomaly is resolved via the gauging of a Peccei‐Quinn axion shift symmetry. The theory describes an inflationary transition from de Sitter to flat Minkowski space, very similar to the Starobinsky inflationary model. The extension to metastable de Sitter superstring vacua is also investigated. The scalar manifold is extended to a much richer manifold, but it contains always as a sub‐manifold. In superstrings the metastability is induced by axions that cure the anomalies in chiral (or even ) supersymmetric vacua via a Green‐Schwarz/Peccei‐Quinn mechanism generalized to four dimensions. We present some typical superstring models and discuss the possible stabilization of the no‐scale modulus.  相似文献   

3.
Motivated by the recently discovered hidden symmetry of the type IIB Green-Schwarz superstring on certain background, the non-semisimple Kac-Moody twisted superalgebra gl(2|2)(2)k is investigated by means of the vector coherent state method and boson-fermion realization. The free field realization of the twisted current superalgebra at general level k is constructed. The corresponding Conformai Field Theory (CFT) has zero central charge. According to the classification theory, this CFT is a nonunitary field theory. After projecting out a U(1) factor and an outer automorphism operator, we get the free field representation of psl(2|2)(2)k, which is the a/gebra of gl(2|2)(2)k modulo the Z4-outer automorphism, the CFT has central charge -2.  相似文献   

4.
By considering the dual Liouville theory emerging in the near-horizon limit, we study the thermodynamics of general rotating black hole with four charges in four dimensions. Both the black hole entropy and temperature are found to agree with the gravitational expectations. The relations between the new Liouville formalism and the anomaly approach are also discussed.  相似文献   

5.
By considering the dual Liouville theory emerging in the near-horizon limit, we study the thermodynamics of general rotating black hole with four charges in four dimensions. Both the black hole entropy and temperature are found to agree with the gravitational expectations. The relations between the new Liouville formalism and the anomaly approach are also discussed.  相似文献   

6.
Thermal modeling of complex systems faces the problems of an effective digitalization of the detailed geometry and properties of the system, calculation of the thermal flows and temperature maps, treatment of the thermal radiation including possible multiple reflections, inclusion of additional external influences, extraction of the radiation pressure from calculated surface data as well as computational effectiveness. In previous publications [1, 2] the solution to these problems have been outlined and a first application to the Pioneer spacecraft have been shown. Here we like to present the application of our thermal modeling to the Rosetta flyby anomaly as well as to the Pioneer anomaly. The analysis outlines that thermal recoil pressure is not the cause of the Rosetta flyby anomaly but likely resolves the anomalous acceleration observed for Pioneer 10.  相似文献   

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Infinite dimensional analysis is developed on an abstract Boson-Fermion Fock space. A general class of Dirac operators acting there is introduced and properties of them are investigated. An index theorem for the Dirac operators is established in terms of a path integral on a loop space. It is shown that the abstract formalism presented here gives a mathematical unification for some models of supersymmetric quantum field theory.  相似文献   

9.
The study starts with the kinematical aspects of singletons and massless particles. It extends to the beginning of a field theory of composite elementary particles and its relations with conformal field theory, including very recent developments and speculations about a possible interpretation of neutrino oscillations and CP violation in this context. This framework was developed during the past twenty years. Based on our deformation philosophy of physical theories, it deals with elementary particles composed of singletons in anti-De Sitter spacetime.  相似文献   

10.
At the critical point in two dimensions, the number of percolation clusters of enclosed area greater than A is proportional to A –1, with a proportionality constant C that is universal. We show theoretically (based upon Coulomb gas methods), and verify numerically to high precision, that . We also derive, and verify to varying precision, the corresponding constant for Ising spin clusters, and for Fortuin–Kasteleyn clusters of the Q = 2, 3 and 4-state Potts models.  相似文献   

11.
We review a number of topics related to block variable renormalisation group transformations of quantum fields on the lattice, and to the emerging perfect lattice actions. We first illustrate this procedure by considering scalar fields. Then we proceed to lattice fermions, where we discuss perfect actions for free fields, for the Gross‐Neveu model and for a supersymmetric spin model. We also consider the extension to perfect lattice perturbation theory, in particular regarding the axial anomaly and the quark gluon vertex function. Next we deal with properties and applications of truncated perfect fermions, and their chiral correction by means of the overlap formula. This yields a formulation of lattice fermions, which combines exact chiral symmetry with an optimisation of further essential properties. We summarise simulation results for these so‐called overlap‐hypercube fermions in the two‐flavour Schwinger model and in quenched QCD. In the latter framework we establish a link to Chiral Perturbation Theory, both, in the p‐regime and in the ϵ‐regime. In particular we present an evaluation of the leading Low Energy Constants of the chiral Lagrangian – the chiral condensate and the pion decay constant – from QCD simulations with extremely light quarks.  相似文献   

12.
<正>The adaptive generalized matrix projective lag synchronization between two different complex networks with non-identical nodes and different dimensions is investigated in this paper.Based on Lyapunov stability theory and Barbalat’s lemma,generalized matrix projective lag synchronization criteria are derived by using the adaptive control method.Furthermore,each network can be undirected or directed,connected or disconnected,and nodes in either network may have identical or different dynamics.The proposed strategy is applicable to almost all kinds of complex networks.In addition,numerical simulation results are presented to illustrate the effectiveness of this method,showing that the synchronization speed is sensitively influenced by the adaptive law strength,the network size,and the network topological structure.  相似文献   

13.
Analytical expression for the nucleation field has been derived for a hard/soft multilayer system with anisotropy perpendicular to the film plane, which depends on the soft thickness Ls, the interface exchange coupling constant Ji and the intrinsic material parameters. Both nucleation field and coercivity decrease as Ls increases. For very small Ls, the coercivity mechanism is pure nucleation and the hysteresis loops are square. As Ls rises, the coercivity mechanism changes from nucleation to pinning gradually, where the hysteresis loops have to be calculated numerically. The critical thickness at which the mechanism varies has been discussed in detail on the basis of easy axis orientation and the interface exchange coupling constant.  相似文献   

14.
The experimental infrared (IR) spectrum of composite wax powder was investigated. The frequency shifts of the C=C anti-symmetrical stretching mode were observed and the experimental cooperativity effect involving Na+···π interaction was suggested. In order to further reveal the nature of cooperativity effect, the interaction energies in Mn+···coronene···CH4 (Mn+ = Li+, Na+, K+, Be2+, Mg2+ or Ca2+) as the model systems of composite wax powder were calculated by using the B3LYP, M06-2X and MP2 methods with 6-311++G** basis set. The results show that the Mn+···π interactions were strengthened upon the formation of ternary complexes. Although the changes of absolute values of the interactions between CH4 and coronene were not obvious, the relative values were considerably significant upon the formation of ternary complexes. The cooperativity effect was perhaps the reason for the formation of notable advantage of composite wax powder upon the introduction of surfactant with cation into wax powder. Reduced density gradient and atoms-in-molecules analysis confirm the cooperativity effect in Mn+···coronene···CH4, and reveal the nature of the formation of the predominant advantage of composite wax powder.  相似文献   

15.
The first manganese complex of picolinic acid (also known as 2-pyridinecarboxylic acid) and 1,10 phenantroline has been synthesized, and its structure has been fully characterized by means of X-Ray diffraction method as well as FT-IR, Raman and UV–vis spectroscopies. In order to provide a deep understanding about the relation among the nonlinear optical properties, structural, spectroscopic and electronic behaviors, density functional theory (DFT) calculations have been performed by using hybrid B3LYP level. The intensive interactions between the bonding orbitals of donor O/N atoms and antibonding orbitals of Mn(II) lone pairs confirm the X-Ray diffraction results. Each of the conditions such as small energy gap between HOMO and LUMO, high energy second order perturbation interaction, elongation of conjugated π system and high spin Mn(II) ion induce the first static hyperpolarizability (β) parameter of investigated complex. The β parameter for [Mn(pic)2(phen)]·H2O complex has been found to be approximately 22 times higher than p-nitroaniline.  相似文献   

16.
The self-consistent Hartree-Fock equation for the He atom is solved using the pseudospectral method. The Feshbachtype autoionization resonance parameters for doubly excited 2s~2, 3s~2, and 4s~2 ~1S states of He have been determined by adding a complex absorbing potential to the Hamiltonian. The Riss–Meyer iterative and Pad′e extrapolation methods are applied to obtain reliable values for the autoionization resonance parameters, which are compared to previous results in the literature.  相似文献   

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