The Schwinger SU(3) Construction - II: Relations between Heisenberg-Weyl and SU(3) Coherent States

The Schwinger oscillator operator representation of SU(3), studied in a previous paper from the representation theory point of view, is analysed to discuss the intimate relationships between standard oscillator coherent state systems and systems of SU(3) coherent states. Both SU(3) standard coherent states, based on choice of highest weight vector as fiducial vector, and certain other specific systems of generalised coherent states, are found to be relevant. A complete analysis is presented, covering all the oscillator coherent states without exception, and amounting to SU(3) harmonic analysis of these states.Comment: Latex, 51 page

Constraints on mass matrices due to measured property of the mixing matrix

It is shown that two specific properties of the unitary matrix $V$ can be expressed directly in terms of the matrix elements and eigenvalues of the hermitian matrix $M$ which is diagonalized by $V$. These are the asymmetry $\Delta(V)= |V_{12}|^2- |V_{21}|^2$, of $V$ with respect to the main diagonal and the Jarlskog invariant $J(V)= {\rm Im}(V_{11}V_{12}^* V_{21}^* V_{22})$. These expressions for $\Delta(V)$ and $J(V)$ provide constraints on possible mass matrices from the available data on $V$.Comment: 5 pages, Late

Bounds on quark mass matrices elements due to measured properties of the mixing matrix and present values of the quark masses

We obtain constraints on possible structures of mass matrices in the quark sector by using as experimental restrictions the determined values of the quark masses at the $M_Z$ energy scale, the magnitudes of the quark mixing matrix elements $V_{\rm ud}$, $V_{\rm us}$, $V_{\rm cd}$, and $V_{\rm cs}$, and the Jarlskog invariant $J(V)$. Different cases of specific mass matrices are examined in detail. The quality of the fits for the Fritzsch and Stech type mass matrices is about the same with $\chi^2/{\rm dof}=4.23/3=1.41$ and $\chi^2/{\rm dof}=9.10/4=2.28$, respectively. The fit for a simple generalization (one extra parameter) of the Fritzsch type matrices, in the physical basis, is much better with $\chi^2/{\rm dof}=1.89/4=0.47$. For comparison we also include the results using the quark masses at the 2 GeV energy scale. The fits obtained at this energy scale are similar to that at $M_Z$ energy scale, implying that our results are unaffected by the evolution of the quark masses from 2 to 91 GeV.Comment: Evolution effects include

Development of aircraft industry in India

It is axiomatic that India requires to self sufficient in the design, development and production of aircraft both for civil and military use, and not, as she is at present, remains entirely dependent on foreign sources. This requirement is keenly felt in the field of defence, since it is appreciated .that the growth of the Armed Forces of a country, in fact their very existence in peace and war, is in modern times directly related to the industrial potential of that country to produce weapons of war. If the two are not properly balanced the Armed Forces would be quite ineffective in fulfilling their role of defending their country in time of emergency

Predictions for the unitarity triangle angles in a new parametrization

A new approach to the parametrization of the CKM matrix, $V$, is considered in which $V$ is written as a linear combination of the unit matrix $I$ and a non-diagonal matrix $U$ which causes intergenerational-mixing, that is $V=\cos\theta I+i\sin\theta U$. Such a $V$ depends on 3 real parameters including the parameter $\theta$. It is interesting that a value of $\theta=\pi/4$ is required to fit the available data on the CKM-matrix including CP-violation. Predictions of this fit for the angles $\alpha$, $\beta$ and $\gamma$ for the unitarity triangle corresponding to $V_{11}V^*_{13} + V_{21} V^*_{23} +V_{31}V^*_{33} =0$, are given. For $\theta$=$\pi/4$, we obtain $\alpha=88.46^\circ$, $\beta=45.046^\circ$ and $\gamma=46.5^\circ$. These values are just about in agreement, within errors, with the present data. It is very interesting that the unitarity triangle is expected to be approximately a right-angled, isosceles triangle. Our prediction $\sin 2\beta = 1$ is in excellent agreement with the value $0.99\pm 0.15\pm 0.05$ reported by the Belle collaboration at the Lepton-Photon 2001 meeting.Comment: 11 pages, latex, no figure

Mapping of non-central potentials under point canonical transformations

Motivated by the observation that all known exactly solvable shape invariant central potentials are inter-related via point canonical transformations, we develop an algebraic framework to show that a similar mapping procedure is also exist between a class of non-central potentials. As an illustrative example, we discuss the inter-relation between the generalized Coulomb and oscillator systems.Comment: 11 pages article in LaTEX (uses standard article.sty). Please check http://www1.gantep.edu.tr/~gonul for other studies of Nuclear Physics Group at University of Gaziante

Spectra of phase point operators in odd prime dimensions and the extended Clifford group

We analyse the role of the Extended Clifford group in classifying the spectra of phase point operators within the framework laid out by Gibbons et al for setting up Wigner distributions on discrete phase spaces based on finite fields. To do so we regard the set of all the discrete phase spaces as a symplectic vector space over the finite field. Auxiliary results include a derivation of the conjugacy classes of ${\rm ESL}(2, \mathbb{F}_N)$.Comment: Latex, 19page

Berry's phase for coherent states of Landau levels

The Berry phases for coherent states and squeezed coherent states of Landau levels are calculated. Coherent states of Landau levels are interpreted as a result of a magnetic flux moved adiabatically from infinity to a finite place on the plane. The Abelian Berry phase for coherent states of Landau levels is an analog of the Aharonov- Bohm effect. Moreover, the non-Abelian Berry phase is calculated for the adiabatic evolution of the magnetic field B.Comment: 4 pages, 1 figur

Hudson's Theorem for finite-dimensional quantum systems

We show that, on a Hilbert space of odd dimension, the only pure states to possess a non-negative Wigner function are stabilizer states. The Clifford group is identified as the set of unitary operations which preserve positivity. The result can be seen as a discrete version of Hudson's Theorem. Hudson established that for continuous variable systems, the Wigner function of a pure state has no negative values if and only if the state is Gaussian. Turning to mixed states, it might be surmised that only convex combinations of stabilizer states give rise to non-negative Wigner distributions. We refute this conjecture by means of a counter-example. Further, we give an axiomatic characterization which completely fixes the definition of the Wigner function and compare two approaches to stabilizer states for Hilbert spaces of prime-power dimensions. In the course of the discussion, we derive explicit formulas for the number of stabilizer codes defined on such systems.Comment: 17 pages, 3 figures; References updated. Title changed to match published version. See also quant-ph/070200