510,431 research outputs found
Exotic tensor gauge theory and duality
Gauge fields in exotic representations of the Lorentz group in D dimensions -
i.e. ones which are tensors of mixed symmetry corresponding to Young tableaux
with arbitrary numbers of rows and columns - naturally arise through massive
string modes and in dualising gravity and other theories in higher dimensions.
We generalise the formalism of differential forms to allow the discussion of
arbitrary gauge fields. We present the gauge symmetries, field strengths, field
equations and actions for the free theory, and construct the various dual
theories. In particular, we discuss linearised gravity in arbitrary dimensions,
and its two dual forms.Comment: 28 pages, LaTeX, references added, minor change
REPLY TO HEP-PH/0211241 "On the extra factor of two in the phase of neutrino oscillations"
Arguments continue to appear in the literature concerning the validity of the
standard oscillation formula. We point out some misunderstandings and try to
explain in simple terms our viewpoint.Comment: 4 pages [1 colored LaTex-fig], AMS-Te
Wave packets and quantum oscillations
We give a detailed analysis of the oscillation formula within the context of
the wave packet formalism. Particular attention is made to insure flavor
eigenstate creation in the physical cases (Delta p not equal 0). This
requirement imposes non instantaneous particle creation in all frames. It is
shown that the standard formula is not only exact when the mass wave packets
have the same velocity, but it is a good approximation when minimal slippage
occurs. For more general situations the oscillation formula contains additional
arbitrary parameters, which allows for the unknown form of the wave packet
envelope.Comment: 15 pages [8 figs], AMS-Te
Pion Form Factor in the Light-Front
The pion electromagnetic form factor is calculated with a light-front quark
model. The "plus" and "minus" component of the electromagnetic current are used
to calculate the electromagnetic form factor in the Breit frame with two models
for the q\bar{q} vertex. The light front constituent quark models describes
very well hadronic wave function for pseudo-scalar and vector particles.
Symmetry problems arinsing in the light-front approach are solved by the pole
dislocation method. The results are compared with new experimental data and
with other quark models.Comment: 4 pages,1 figure (eps), Latex,AIP style.To appear in the proceedings
"IX Hadron Physics and VII Relativistic Aspects of Nuclear Physics: A Joint
Meeting on QCD and QGP, Hadron Physics-RANP,2004,Angra dos Reis, Rio de
Janeiro,Brazil.(some references are added and small mistakes are corrected.
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