6,193 research outputs found

### Recent Results on Light Meson Physics

Some recent results on light meson physics are reviewed. The new evidence of
low mass scalar mesons together with an improved measurement of the phi
radiative decays in scalar mesons, give new insight into the nature and the
structure of the scalar spectrum. The evidence of new states with a mass close
to twice the proton mass, and a new analysis of the gluonium content of the
eta' are discussed.Comment: Invited talk at XXIII Physics in Collision Conference (PIC03)
Zeuthen, Germany, June 2003, 10 pages, LaTex, 9 eps figures. PSN FRAT1

### Geometric transport along circular orbits in stationary axisymmetric spacetimes

Parallel transport along circular orbits in orthogonally transitive
stationary axisymmetric spacetimes is described explicitly relative to Lie
transport in terms of the electric and magnetic parts of the induced
connection. The influence of both the gravitoelectromagnetic fields associated
with the zero angular momentum observers and of the Frenet-Serret parameters of
these orbits as a function of their angular velocity is seen on the behavior of
parallel transport through its representation as a parameter-dependent Lorentz
transformation between these two inner-product preserving transports which is
generated by the induced connection. This extends the analysis of parallel
transport in the equatorial plane of the Kerr spacetime to the entire spacetime
outside the black hole horizon, and helps give an intuitive picture of how
competing "central attraction forces" and centripetal accelerations contribute
with gravitomagnetic effects to explain the behavior of the 4-acceleration of
circular orbits in that spacetime.Comment: 33 pages ijmpd latex article with 24 eps figure

### Kerr metric, static observers and Fermi coordinates

The coordinate transformation which maps the Kerr metric written in standard
Boyer-Lindquist coordinates to its corresponding form adapted to the natural
local coordinates of an observer at rest at a fixed position in the equatorial
plane, i.e., Fermi coordinates for the neighborhood of a static observer world
line, is derived and discussed in a way which extends to any uniformly
circularly orbiting observer there.Comment: 15 page latex iopart class documen

### Inertial effects of an accelerating black hole

We consider the static vacuum C metric that represents the gravitational
field of a black hole of mass $m$ undergoing uniform translational acceleration
$A$ such that $mA<1/(3\sqrt{3})$. The influence of the inertial acceleration on
the exterior perturbations of this background are investigated. In particular,
we find no evidence for a direct spin-acceleration coupling.Comment: Proceedings of the XVI Conference of the Italian Society for General
Relativity and Gravitation (SIGRAV), Vietri (SA), September 13-16, 2004.
Prepared using revtex4 macro

### Energy and angular momentum of general 4-dimensional stationary axi-symmetric spacetime in teleparallel geometry

We derive an exact general axi-symmetric solution of the coupled
gravitational and electromagnetic fields in the tetrad theory of gravitation.
The solution is characterized by four parameters $M$ (mass), $Q$ (charge), $a$
(rotation) and $L$ (NUT). We then, calculate the total exterior energy using
the energy-momentum complex given by M{\o}ller in the framework of
Weitzenb$\ddot{o}$ck geometry. We show that the energy contained in a sphere is
shared by its interior as well as exterior. We also calculate the components of
the spatial momentum to evaluate the angular momentum distribution. We show
that the only non-vanishing components of the angular momentum is in the Z
direction.Comment: Latex. Will appear in IJMP

### Circular holonomy in the Taub-NUT spacetime

Parallel transport around closed circular orbits in the equatorial plane of
the Taub-NUT spacetime is analyzed to reveal the effect of the gravitomagnetic
monopole parameter on circular holonomy transformations. Investigating the
boost/rotation decomposition of the connection 1-form matrix evaluated along
these orbits, one finds a situation that reflects the behavior of the general
orthogonally transitive stationary axisymmetric case and indeed along Killing
trajectories in general.Comment: 9 pages, LaTeX iopart class, no figure

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