The (constrained) canonical reduction of four-dimensional self-dual SU(2) and SU(3) Yang–Mills theory to two-dimensional nonlinear Schrödinger (NS) and Korteweg–de Vries (KdV) equations are considered. The Bäcklund transformations (BTs) are implemented to obtain new classes of exact solutions for the reduced two-dimensional NS and KdV models. 相似文献
In order to remove some of the unsatisfactory features of the GIM model, we consider15-admixture in SU(4). ΔC=±ΔS decays remain unaffected. Lee-Sugawara sum-rule is obtained.15-admixture is extended then to63-admixture in SU(8). The most general Hamiltonian (Hw∼63⊕720⊕1232) in SU(8) is found to give Lee-Sugawara relation and Σ++=0 forS-wave decays of uncharmed baryons. Decay amplitude relations for ΔC=−1, ΔS=0 mode are obtained. 相似文献
An Casson invariant of a knot is an integer which can be thought of as an algebraic-topological count of the number of characters of representations of the knot group which take a longitude into a given conjugacy class. For fibered knots, these invariants can be characterized as Lefschetz numbers which, for generic conjugacy classes, can be computed using a recursive algorithm of Atiyah and Bott, as adapted by Frohman. Using a new idea to solve the Atiyah-Bott recursion (as simplified by Zagier), we derive universal formulae which explicitly compute the invariants for all . Our technique is based on our discovery that the generating functions associated to the relevant Lefschetz numbers (and polynomials) satisfy certain integral equations.
Exact quantum states of the time-dependent quadratic Hamiltonian system are investigated using SU(1,1) Lie algebra. We realized
SU(1,1) Lie algebra by defining appropriate SU(1,1) generators and derived exact wave functions using this algebra for the
system. Raising and lowering operators of SU(1,1) Lie algebra expressed by multiplying a time-constant magnitude and a time-dependent
phase factor. Two kinds of the SU(1,1) coherent states, i.e., even and odd coherent states and Perelomov coherent states are
studied. We applied our result to the Caldirola–Kanai oscillator. The probability density of these coherent states for the
Caldirola–Kanai oscillator converged to the center as time goes by, due to the damping constant γ. All the coherent state
probability densities for the driven system are somewhat deformed.
PACS Numbers: 02.20.Sv, 03.65.-w, 03.65.Fd 相似文献
A generalized Bloch sphere, in which the states of a quantum entity of arbitrary dimension are geometrically represented, is investigated and further extended, to also incorporate the measurements. This extended representation constitutes a general solution to the measurement problem, inasmuch it allows to derive the Born rule as an average over hidden-variables, describing not the state of the quantum entity, but its interaction with the measuring system. According to this modelization, a quantum measurement is to be understood, in general, as a tripartite process, formed by an initial deterministic decoherence-like process, a subsequent indeterministic collapse-like process, and a final deterministic purification-like process. We also show that quantum probabilities can be generally interpreted as the probabilities of a first-order non-classical theory, describing situations of maximal lack of knowledge regarding the process of actualization of potential interactions, during a measurement. 相似文献
This paper generalizes some known solitary solutions of a time-dependent Hamiltonian in two ways: The time-dependent field can be an elliptic function, and the time evolution is obtained for a complete set of basis vectors. The latter makes it feasible to consider arbitrary initial conditions. The former makes it possible to observe a beating caused by the non-harmonicity of the driving field. 相似文献
Recently we initiated the study of spherical T-duality for spacetimes that are principal -bundles (Bouwknegt et al., to appear). In this paper, we extend spherical T-duality to spacetimes that are oriented non-principal -bundles. There are several interesting new examples in this case and a new phenomenon appearing in the non-principal case is the existence of infinitely many spherical T-duals. 相似文献
This article reviews the most common, useful methods for the chiral determination of amphetamine (AM) and AM-derived designer drugs in different of matrix, including blood, hair, urine, medicaments or standard solutions, taking into consideration articles published in the past 15 years. We consider chromatographic methods (e.g., gas, liquid, high-performance liquid, and thin layer). We describe several types of chiral derivatization reagent, mobile-phase additive and chiral stationary phase commonly used in the chromatographic methods. Tables summarize basic information about conditions (e.g., type of column and mobile phase), detection mode and reference data for each procedure. 相似文献