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941.
Isotopic liftings of algebraic structures are investigated in the context of Clifford algebras, where it is defined a new
product involving an arbitrary, but fixed, element of the Clifford algebra. This element acts as the unit with respect to
the introduced product, and is called isounit. We construct isotopies in both associative and non-associative arbitrary algebras, and examples of these constructions are
exhibited using Clifford algebras, which although associative, can generate the octonionic, non-associative, algebra. The
whole formalism is developed in a Clifford algebraic arena, giving also the necessary pre-requisites to introduce isotopies
of the exterior algebra. The flavor hadronic symmetry of the six u,d,s,c,b,t quarks is shown to be exact, when the generators of the isotopic Lie algebra
are constructed, and the unit of the isotopic Clifford algebra is shown to be a function of the six quark masses. The limits
constraining the parameters, that are entries of the representation of the isounit in the isotopic group SU(6), are based
on the most recent limits imposed on quark masses. 相似文献
942.
Jingsong He Kelei Tian Angela Foerster Wen-Xiu Ma 《Letters in Mathematical Physics》2007,81(2):119-134
Based on the Orlov and Shulman’s M operator, the additional symmetries and the string equation of the CKP hierarchy are established, and then the higher order
constraints on L
l
are obtained. In addition, the generating function and some properties are also given. In particular, the additional symmetry
flows form a new infinite dimensional algebra , which is a subalgebra of W
1+∞.
相似文献
943.
The ionic conduction properties of undoped and doped Tl4HgI6 were investigated using electrical conductivity, dielectrics, differential scanning calorimetry, and X-ray diffraction techniques.
The heavy Tl+-ions diffusion was activated at high temperature, whereas low conductivity at the lower temperature suggested electronic
contribution in undoped Tl4HgI6. The partial replacement of heavy Tl+ ion by suitable cations (Ag+ and Cu+) enhanced the conductivity by several orders of magnitude, whereas diminution in conductivity results with increasing dopants’
concentration in Tl4HgI6. These results can be interpreted in terms of a lattice contraction and vacancy–vacancy interaction (leading to the cluster
formation), respectively. The dielectric values of undoped Tl4HgI6 system gradually increasing with temperature, followed by a sharp change, were observed around 385 K and can be explained
on the basis of increasing number of space charge polarization and ions jump orientation effects. The activation energy of
undoped and doped Tl4HgI6 systems were calculated, and it was found that ionic conductivity activation energy for 5 mol% of cation dopants is much
lower than that of undoped one, and also 10 mol% doped Tl4HgI6 systems. 相似文献
944.
We have calculated the one-neutron absorption cross-section and the longitudinal momentum distribution of the core fragment
coming out from the breakup of 11Be and 19C on 9Be target at 63 MeV/A and 88 MeV/A beam energies respectively. The reaction mechanism is treated within the framework of the
eikonal approximation. The effective range of the nuclear interaction between the core and the valence neutron within the
projectile has been determined by comparing the predicted stripping cross-section with the recently measured one. The effective
range for 19C has been found to be smaller than that for 11Be. It qualitatively indicates that 19C is slightly more halo than 11Be. The smaller width, predicted as well as measured, of the LMD of 18C than 10Be also strengthens this fact. The experimental data concerning the LMD of core fragments have been well represented.
相似文献
945.
Marco Castrillón López Jaime Muñz Masquó 《International Journal of Theoretical Physics》2007,46(4):1020-1026
It is proved that the Euler–Lagrange equations of a Yang-Mills type Lagragian is independent with respect to the chosen pairing
in the Lie algebra. Moreover, the Hamilton-Cartan equations of these Lagrangians are obtained and proved to be also independent
with respect to the pairing.
PACS Numbers 2003: 02.20.Qs, 02.20.Sv, 02.20.Tw, 02.40.Ma, 02.40.Vh, 11.10.Ef, 11.15.Kc
Mathematics Subject Classification 2000: Primary 70S15, Secondary 58A20, 58E15, 58E30, 70S05, 70S10, 81T13 相似文献
946.
We present the study of exact inhomogeneous cosmological solutions to a four-dimensional low energy limit of string theory
containing non-minimal interacting electromagnetic, dilaton and axion fields. We focus at Einstein-Rosen solutions of Einstein-Maxwell-dilaton-axion
equations. Several cases are analyzed and some of them have asymptotically velocity-term dominated (AVTD) singularities. 相似文献
947.
Anirudh Pradhan Purnima Pandey Kanti Jotania Mahesh Kumar Yadav 《International Journal of Theoretical Physics》2007,46(11):2774-2787
Plane symmetric viscous fluid cosmological models of the universe with a variable cosmological term are investigated. The
viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density whereas the coefficient of shear
viscosity is to be proportional to rate of expansion in the model. We have also obtained a special model in which the shear
viscosity is assumed to be zero. The cosmological constant Λ is found to be a decreasing function of time and a positive which is supported by results from recent supernovae Ia observations.
Some physical and geometric properties of the models are also discussed. 相似文献
948.
Anjan Biswas Swapan Konar Essaid Zerrad 《International Journal of Theoretical Physics》2007,46(1):157-169
The intra-channel collision of optical solitons, with dual-power law nonlinearity, is studied in this paper by the aid of
quasi-particle theory. The perturbation terms that are considered in this paper are the nonlinear gain and saturable amplifiers
along with filters. The suppression of soliton-soliton interaction, in presence of these perturbation terms, is acheived.
The numerical simulations support the quasi-particle theory.
OCIS codes: 060.2310; 060.4510; 060.5530; 190.3270; 190.4370. 相似文献
949.
A theoretical framework is demonstrated to evaluate the degree of entanglement of bit states in quantum computing. Separability
of general superposition of Hilbert space unit vectors is discussed, and criteria in amplitude as well as in phase are derived.
By these criteria the possibility of different quantum gates such as controlled not (CN), controlled controlled not (CCN),
controlled rotation (CR), and controlled phase shift (CPS), to create the entanglement is examined. Furthermore, the selection
of measurement mode external to the quantum system is incorporated in the formula using Kronecker delta (δ
kx
), introducing the concept of dynamic entanglement. With this the process of wavefunction collapse upon measurement is understood as the result of the activation of the dynamic
entanglement. A firefly in a box model is used to show a pure state of ontological uncertainty, which is in a dynamically
entangled state in Hilbert space. 相似文献
950.
N. Sankara Subramanian R. Vivek Sabaapathy P. Vickraman G. Vimal Kumar R. Sriram B. Santhi 《Ionics》2007,13(5):323-328
P-type porous silicon (PS) structure has been prepared by anodic electrochemical etching process under optimized conditions.
Photoluminescence studies of the PS structure show emission at longer wavelengths (red) for the excitation at 365 nm. Scanning
electron microscope investigations of the PS surface confirm the formation of uniform porous structure, and the pore diameter
have been estimated as 25 μm. Pd:SnO2/PS/p-Si heterojunction with top gold ohmic contact developed by conventional methods has been used as the sensor device.
Sensing properties of the device towards liquefied petroleum gas (LPG) and NO2 gas have been investigated in an indigenously developed sensor test rig. The response and recovery characteristics of the
sensor device at different operating temperatures show short response time for LPG. From the studies, maximum sensitivity
and optimum operating temperature of the device towards LPG and NO2 gas sensing has been estimated as 69% at 180 °C and 52% at 220 °C, respectively. The developed sensor device shows a short
response time of 25 and 57 s for sensing LPG and NO2 gases, respectively.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006. 相似文献