16 research outputs found
Natural Diagonal Riemannian Almost Product and Para-Hermitian Cotangent Bundles
We obtain the natural diagonal almost product and locally product structures
on the total space of the cotangent bundle of a Riemannian manifold. We find
the Riemannian almost product (locally product) and the (almost) para-Hermitian
cotangent bundles of natural diagonal lift type. We prove the characterization
theorem for the natural diagonal (almost) para-K\"ahlerian structures on the
total spaces of the cotangent bundle.Comment: 10 pages, will appear in Czechoslovak Mathematical Journa
Superconformal N=2, D=5 matter with and without actions
We investigate N=2, D=5 supersymmetry and matter-coupled supergravity
theories in a superconformal context. In a first stage we do not require the
existence of a Lagrangian. Under this assumption, we already find at the level
of rigid supersymmetry, i.e. before coupling to conformal supergravity, more
general matter couplings than have been considered in the literature. For
instance, we construct new vector-tensor multiplet couplings, theories with an
odd number of tensor multiplets, and hypermultiplets whose scalar manifold
geometry is not hyperkaehler.
Next, we construct rigid superconformal Lagrangians. This requires some extra
ingredients that are not available for all dynamical systems. However, for the
generalizations with tensor multiplets mentioned above, we find corresponding
new actions and scalar potentials. Finally, we extend the supersymmetry to
local superconformal symmetry, making use of the Weyl multiplet. Throughout the
paper, we will indicate the various geometrical concepts that arise, and as an
application we compute the non-vanishing components of the Ricci tensor of
hypercomplex group manifolds. Our results can be used as a starting point to
obtain more general matter-couplings to Poincare supergravity.Comment: 67 pages; v2: title of reference changed and small editing
corrections; v3: small typing errors corrected, version published in JHEP;
v4: typos corrected; v5: additional term in (2.109) and (4.11); v6: change of
order of indices in (2.89
Librations with Mass Transfer in the Sun-Jupiter System
Trojan-type motion is analytically and numerically studied under mass transfer between the primaries with conservation of their total orbital angular momentum. We prove theoretically and numerically our new result that angular libration widths change as m^1/4, (m - Jupiter mass) if they are throughout smaller than about 60 arcd. Numerical examples show that for initial libration widths larger than about 60 arcd, the Trojan is ultimately driven out of the libration domain, becoming an ordinary asteroid, if Jupiter's transferred mass increases by a factor less than about two. Certain processes occurring in our solar system and in extrasolar planetary systems lead to a decrease of the Trojan's libration amplitude, while other processes lead to an increase, respectively