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1.
An(n?1)/2+1 parameter, solution of the Yang Baxter equation is presented giving rise to the quantum Group \(GL_{X;q_{ij} } (n)\) . Determinant and inverse are constructed. The group acts covariantly on a quantum vector space of non-commutative coordinates. The associated exterior space can be identified with the differentials exhibiting a multiparameter deformed differential calculus following the construction of Wess and Zumino.  相似文献   

2.
Abhijit Sen 《Pramana》2009,73(6):1041-1057
Flavour equilibration for a thermally equilibrated but chemically non-equilibrated quark-gluon plasma is presented. Flavour equilibration is studied enforcing baryon number conservation. In addition to the usual processes like single additional gluon production ggggg and its reverse and quark-antiquark pair production by gluon pair fusion ggq i q ı and reverse thereof, processes like quark-flavour interchanging q i q ı q j $ q_{\bar j} $ q_{\bar j} is also considered. The degree of equilibration is studied comparatively for various reactions/constraints that are being considered.  相似文献   

3.
We discuss the algebras, representations, and thermodynamics of quantum group bosonic gas models with two different symmetries: GL p,q (2) and . We establish the nature of the basic numbers which follow from these GL p,q (2)- and -invariant bosonic algebras. The Fock space representations of both of these quantum group invariant bosonic oscillator algebras are analyzed. It is concisely shown that these two quantum group invariant bosonic particle gases have different algebraic and high-temperature thermo-statistical properties.  相似文献   

4.
We study a free field realization of the elliptic quantum algebra Uq,p($ \widehat{sl_3 } $ \widehat{sl_3 } ) for arbitrary level k. We give the free field realization of elliptic analog of Drinfeld current associated with Uq,p($ \widehat{sl_3 } $ \widehat{sl_3 } ) for arbitrary level k. In the limit p → 0, q → 1 our realization reproduces Wakimoto realization for the affine Lie algebra $ \widehat{sl_3 } $ \widehat{sl_3 } .  相似文献   

5.
In a model-independent approach the data on ππ → ππ, K $ \bar K $ \bar K , ηη, ηη′ in the I G J PC = 0+0++ channel and on the Kπ scattering in the $ I\left( {J^P } \right) = \frac{1} {2}\left( {0^ + } \right) $ I\left( {J^P } \right) = \frac{1} {2}\left( {0^ + } \right) channel are analyzed jointly for studying the status and QCD nature of the f 0- and the K*0-mesons. It is shown that in the 1500-MeV region, there are two states, wide (interpreted as a glueball) and narrow (q $ \bar q $ \bar q ). In the Kπ-scattering data analysis, the proof for the K*0(900) is given.  相似文献   

6.
The BRAHMS measurement of proton-to-pion ratios in Au+Au and p+p collisions at $ \sqrt {s_{NN} } $ \sqrt {s_{NN} } = 62.4 GeV and $ \sqrt {s_{NN} } $ \sqrt {s_{NN} } = 200 GeV is presented as a function of transverse momentum and collision centrality within the pseudorapidity range 0 ≤ η ≤ 3. The baryo-chemical potential, μ B , for the indicated data spans from μ B ≈ 26 MeV ($ \sqrt {s_{NN} } $ \sqrt {s_{NN} } 200 GeV, η ≈ 0) to μ B ∼ 260 MeV ($ \sqrt {s_{NN} } $ \sqrt {s_{NN} } = 62.4 GeV, η ≈ 3) [1]. The p/πratio measured for Au+Au system at $ \sqrt {s_{NN} } $ \sqrt {s_{NN} } 62.4 GeV, η ≈ 3 reaches astounding value of 8–10 at p T > 1.5 GeV/c. For these energy and pseudorapidity interval no centrality dependency of p/π ratio is observed. Moreover, the baryon-to-meson ratio of nucleus-nucleus data are consistent with results obtained for p+p interactions.  相似文献   

7.
The time-dependent and time-independent CP asymmetries $ A_{CP}^{B_q^0 \to f} \left( \tau \right) $ A_{CP}^{B_q^0 \to f} \left( \tau \right) and $ A_{CP}^{B_q^0 \to f} \left( {\hat s} \right) $ A_{CP}^{B_q^0 \to f} \left( {\hat s} \right) for rare semileptonic and radiative leptonic decays of B mesons are calculated by the method of helicity amplitudes. The sensitivity of CP asymmetries to various extensions of the Standard Model that have an operator basis that is identical to the operator basis of the Standard Model is investigated. It is shown that, by combining information about the form of the charge lepton asymmetry A FB at small values of the square of the invariant dilepton mass and information about the average value of the time-dependent CP asymmetry, one can in principle determine the relative phases of the Wilson coefficients C 7γ , C 9V , and C 10A in the effective Hamiltonian for b → {d, s}ℓ+ transitions.  相似文献   

8.
The Blume-Emery-Griffiths model with the dipole-quadrupole interaction ($ \ell = \frac{I} {J} $ \ell = \frac{I} {J} ) has been simulated using a cellular automaton algorithm improved from the Creutz cellular automaton (CCA) on the face centered cubic (fcc) lattice. The finite-size scaling relations and the power laws of the order parameter (M) and the susceptibility (χ) are proposed for the dipole-quadrupole interaction (ℓ). The dipole-quadrupole critical exponent δχ has been estimated from the data of the order parameter (M) and the susceptibility (χ). The simulations have been done in the interval $ 0 \leqslant \ell = \frac{I} {J}0 \leqslant 0.01 $ 0 \leqslant \ell = \frac{I} {J}0 \leqslant 0.01 for $ d = \frac{D} {J} = 0,k = \frac{K} {J} = 0 $ d = \frac{D} {J} = 0,k = \frac{K} {J} = 0 and $ h = \frac{H} {J} = 0 $ h = \frac{H} {J} = 0 parameter values on a face centered cubic (fcc) lattice with periodic boundary conditions. The results indicate that the effect of the ℓ parameter is similar to the external magnetic field (h). The critical exponent δ are in good agreement with the universal value (δ h = 5) of the external magnetic field.  相似文献   

9.
It was proved in the previous work that there must be a maximal possible accretion rate $ \dot M_{max} $ \dot M_{max} for a slim disk. Here we discuss how the value of $ \dot M_{max} $ \dot M_{max} depends on the two fundamental parameters of the disk, namely the mass of the central black hole M and the viscosity parameter α. It is shown that $ \dot M_{max} $ \dot M_{max} increases with decreasing α, but is almost independent of M if $ \dot M_{max} $ \dot M_{max} is measured by the Eddington accretion rate $ \dot M_{Edd} $ \dot M_{Edd} , which is in turn proportional to M.  相似文献   

10.
We present the measurement of directed flow (v 1) for the identified particles, namely, Λ, $ \bar \Lambda $ \bar \Lambda and K s 0, as a function of rapidity and centrality in Au+Au collisions at $ \sqrt {s_{NN} } $ \sqrt {s_{NN} } = 200 GeV and 62.4 GeV. The measurement is based on the run IV data obtained by the STAR experiment at RHIC. In order to enhance event plane resolution, we use tracks reconstructed from the Forward Time Projection Chambers (FTPCs), together with the sideward deflection of spectator neutrons measured by the STAR’s Shower Maximum Detector at Zero Degree Calorimeters (ZDC-SMDs). We find that for 200 GeV, proton and antiproton v 1 is less than 1%, the K s 0 Λ, $ \bar \Lambda $ \bar \Lambda v 1 is less than 2%; for 62 GeV, proton v 1 is less than 1% and antiproton is less than 2%, v 1 for K s 0, Λ, $ \bar \Lambda $ \bar \Lambda is less than 2% in Au+Au collisions at 200 GeV.  相似文献   

11.
Zafar Ahmed 《Pramana》2009,73(2):323-328
We find that a non-differentiability occurring whether in real or imaginary part of a complex $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} -symmetric potential causes a scarcity of the real discrete eigenvalues despite the real part alone possessing an infinite spectrum. We demonstrate this by perturbing the real potentials x 2 and |x| by imaginary $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} -symmetric potentials ix/it|x| and ix, respectively.  相似文献   

12.
G. Lévai 《Pramana》2009,73(2):329-335
The $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} symmetry of the Coulomb potential and its solutions are studied along trajectories satisfying the $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} symmetry requirement. It is shown that with appropriate normalization constant the general solutions can be chosen $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} -symmetric if the L parameter that corresponds to angular momentum in the Hermitian case is real. $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} symmetry is spontaneously broken, however, for complex L values of the form L = −1/2 + iλ. In this case the potential remains $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} -symmetric, while the two independent solutions are transformed to each other by the $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} operation and at the same time, the two series of discrete energy eigenvalues turn into each other’s complex conjugate.  相似文献   

13.
Supersymmetric quantum mechanics is constructed in a new non-Hermitian representation. Firstly, the map between the partner operators H (±) is chosen antilinear. Secondly, both these components of a super-Hamiltonian $ \mathcal{H} $ \mathcal{H} are defined along certain topologically non-trivial complex curves r (±)(x) which spread over several Riemann sheets of the wave function. The non-uniqueness of our choice of the map $ \mathcal{T} $ \mathcal{T} between ‘tobogganic’ partner curves r (+)(x) and r (−)(x) is emphasized.  相似文献   

14.
We show results for the universal anomalous dimension γuni(j) of Wilson twist-2 operators in the $ \mathcal{N} $ \mathcal{N} = 4 Supersymmetric Yang-Mills theory in the first three orders of perturbation theory. These expressions are obtained by extracting the most complicated contributions from the corresponding anomalous dimensions in QCD.  相似文献   

15.
Optical activity of xenon atoms in the vacuum UV range induced by circularly polarized laser light is studied theoretically. The optical activity arises in the vicinity of the autoionizing state 5p 5(2 P 1/2)8s′$ \left[ {\frac{1} {2}} \right]_1 $ \left[ {\frac{1} {2}} \right]_1 as a result of its coupling via the laser field with the discrete state 5p 5(2 P 3/2)7p $ \left[ {\frac{1} {2}} \right]_1 $ \left[ {\frac{1} {2}} \right]_1 . Polarization variations of the vacuum UV radiation upon its propagation through the atomic medium are calculated, and the possibility of controlling this polarization is discussed. Manifestations of nonresonant coupling of the discrete state with the broad autoionizing state 5p 5(2 P 1/2)6d′$ \left[ {\frac{1} {2}} \right]_1 $ \left[ {\frac{1} {2}} \right]_1 induced by the overlap of the Rydberg autoionizing series in xenon are studied.  相似文献   

16.
We construct a two-parameter deformed SUSY algebra for the system of n ordinary fermions and n(q 1,q 2)-deformed bosons called Fibonacci oscillators with -symmetry. We then analyze the Fock space representation of the algebra constructed. We obtain the total deformed Hamiltonian and the energy levels together with their degeneracies for the system. We also consider some physical applications of the Fibonacci oscillators with -symmetry, and discuss the main reasons to consider two distinct deformation parameters.  相似文献   

17.
Qing-Hai Wang 《Pramana》2009,73(2):315-322
Two-dimensional $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} -symmetric quantum-mechanical systems with the complex cubic potential V 12 = x 2 + y 2 + igxy 2 and the complex Hénon-Heiles potential V HH = x 2 +y 2 +ig(xy 2x 3/3) are investigated. Using numerical and perturbative methods, energy spectra are obtained to high levels. Although both potentials respect the $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} symmetry, the complex energy eigenvalues appear when level crossing happens between same parity eigenstates.  相似文献   

18.
This paper deals with the higher spin Dirac operator Q2,1 acting on functions taking values in an irreducible representation space for so(m) with highest weight $ (\tfrac{5} {2},\tfrac{3} {2},\tfrac{1} {2},...,\tfrac{1} {2}) $ (\tfrac{5} {2},\tfrac{3} {2},\tfrac{1} {2},...,\tfrac{1} {2}) . This operator acts as a toy model for generalizations of the classical Rarita—Schwinger equations in Clifford analysis. Polynomial null solutions for this operator are studied in particular.  相似文献   

19.
Sanjib Meyur  S. Dednath 《Pramana》2009,73(4):627-637
A new kind of $ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} and non-$ \mathcal{P}\mathcal{T} $ \mathcal{P}\mathcal{T} -symmetric complex potentials are constructed from a group theoretical viewpoint of the sl(2,C) potential algebras. The real eigenvalues and the corresponding regular eigenfunctions are also obtained. The results are compared with the ones obtained before.  相似文献   

20.
Oscillations of neutral meson (K 0-$ \overline {K^0 } $ \overline {K^0 } , D 0-$ \overline {D^0 } $ \overline {D^0 } , and B 0-$ \overline {B^0 } $ \overline {B^0 } are extremely sensitive to the meson and antimeson energies at rest. This energy is determined as mc 2—with the corresponding inertial mass—and as the energy of gravitational interaction. Assuming that the CPT theorem is correct for inertial masses and estimating the gravitational potential for which the largest contribution originates from the field of the galaxy center, we obtain the estimate from experimental data on K 0-$ \overline {K^0 } $ \overline {K^0 } oscillations:
$ \left| {\left( {\frac{{m_g }} {{m_i }}} \right)_{K^0 } - \left( {\frac{{m_g }} {{m_i }}} \right)_{\overline {K^0 } } } \right| \leqslant 8 \times 10^{ - 13} , at C.L. = 90\% $ \left| {\left( {\frac{{m_g }} {{m_i }}} \right)_{K^0 } - \left( {\frac{{m_g }} {{m_i }}} \right)_{\overline {K^0 } } } \right| \leqslant 8 \times 10^{ - 13} , at C.L. = 90\%   相似文献   

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