1,380 research outputs found

### Parity violating vertices for spin-3 gauge fields

The problem of constructing consistent parity-violating interactions for
spin-3 gauge fields is considered in Minkowski space. Under the assumptions of
locality, Poincar\'e invariance and parity non-invariance, we classify all the
nontrivial perturbative deformations of the abelian gauge algebra. In
space-time dimensions $n=3$ and $n=5$, deformations of the free theory are
obtained which make the gauge algebra non-abelian and give rise to nontrivial
cubic vertices in the Lagrangian, at first order in the deformation parameter
$g$. At second order in $g$, consistency conditions are obtained which the
five-dimensional vertex obeys, but which rule out the $n=3$ candidate.
Moreover, in the five-dimensional first order deformation case, the gauge
transformations are modified by a new term which involves the second de
Wit--Freedman connection in a simple and suggestive way.Comment: 27 pages, 1 table, revtex4, typos correcte

### Parametric statistics of zeros of Husimi representations of quantum chaotic eigenstates and random polynomials

Local parametric statistics of zeros of Husimi representations of quantum
eigenstates are introduced. It is conjectured that for a classically fully
chaotic systems one should use the model of parametric statistics of complex
roots of Gaussian random polynomials which is exactly solvable as demonstrated
below. For example, the velocities (derivatives of zeros of Husimi function
with respect to an external parameter) are predicted to obey a universal
(non-Maxwellian) distribution ${d P(v)}/{dv^2} = 2/(\pi\sigma^2)(1 +
|v|^2/\sigma^2)^{-3},$ where $\sigma^2$ is the mean square velocity. The
conjecture is demonstrated numerically in a generic chaotic system with two
degrees of freedom. Dynamical formulation of the ``zero-flow'' in terms of an
integrable many-body dynamical system is given as well.Comment: 13 pages in plain Latex (1 figure available upon request

### g = 2 as a Gauge Condition

Charged matter spin-1 fields enjoy a nonelectromagnetic gauge symmetry when
interacting with vacuum electromagnetism, provided their gyromagnetic ratio is
2.Comment: 5 pages, REVTeX, submitted to Phys Rev D Brief Report

### Charged coherent states related to su_{q}(2) covariance

A new kind of q-deformed charged coherent states is constructed in Fock space
of two-mode q-boson system with su_{q}(2) covariance and a resolution of unity
for these states is derived. We also present a simple way to obtain these
coherent states using state projection method.Comment: 7 pages. To appear in Modern Phyics Letter:

### Multi-Dimensional Hermite Polynomials in Quantum Optics

We study a class of optical circuits with vacuum input states consisting of
Gaussian sources without coherent displacements such as down-converters and
squeezers, together with detectors and passive interferometry (beam-splitters,
polarisation rotations, phase-shifters etc.). We show that the outgoing state
leaving the optical circuit can be expressed in terms of so-called
multi-dimensional Hermite polynomials and give their recursion and
orthogonality relations. We show how quantum teleportation of photon
polarisation can be modelled using this description.Comment: 10 pages, submitted to J. Phys. A, removed spurious fil

### Parity-dependent squeezing of light

A parity-dependent squeezing operator is introduced which imposes different
SU(1,1) rotations on the even and odd subspaces of the harmonic oscillator
Hilbert space. This operator is used to define parity-dependent squeezed states
which exhibit highly nonclassical properties such as strong antibunching,
quadrature squeezing, strong oscillations in the photon-number distribution,
etc. In contrast to the usual squeezed states whose $Q$ and Wigner functions
are simply Gaussians, the parity-dependent squeezed states have much more
complicated $Q$ and Wigner functions that exhibit an interesting interference
in phase space. The generation of these states by parity-dependent quadratic
Hamiltonians is also discussed.Comment: accepted for publication in J. Phys. A, LaTeX, 11 pages, 12 figures
(compressed PostScript, available at
http://www.technion.ac.il/~brif/graphics/pdss_graph ). More information on
http://www.technion.ac.il/~brif/science.htm

### Bargmann-Michel-Telegdi equation and one-particle relativistic approach

A reexamination of the semiclassical approach of the relativistic electron
indicates a possible variation of its helicity for electric and magnetic static
fields applied along its global motion due to zitterbewegung effects,
proportional to the anomalous part of the magnetic moment.Comment: 10 pages, LATEX2E, uses amsb

### Improvement of measurement accuracy in SU(1,1) interferometers

We consider an SU(1,1) interferometer employing four-wave mixers that is fed
with two-mode states which are both coherent and intelligent states of the
SU(1,1) Lie group. It is shown that the phase sensitivity of the interferometer
can be essentially improved by using input states with a large photon-number
difference between the modes.Comment: LaTeX, 5 pages, 1 figure (compressed PostScript, available at
http://www.technion.ac.il/~brif/graphics/interfer_graph/qopt.ps.gz ). More
information on http://www.technion.ac.il/~brif/science.htm

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