24,195 research outputs found
TRYING TO FIT AN OVAL SHAPED ISLAND INTO A SQUARE CONSTITUTION: ARGUMENTS FOR PUERTO RICAN STATEHOOD
This Comment focuses on the limits placed on Puerto Rico under the United States Constitution and concludes that Puerto Rico must become the 51st state to improve its status under the Constitution. It explores Puerto Rico\u27s relationship with the United States and its unusual position under the Constitution. This Comment then examines the voting rights issues facing Puerto Ricans, including a First Circuit case which denied Puerto Ricans the right to vote in presidential elections. The Comment concludes that this case was correctly decided and the Supreme Court, in other decisions, has only recognized a limited right to vote under the Equal Protection Clause. Based on this case law, the Comment argues that Puerto Rico must become the 51st state to alleviate these voting rights issues
An asset and liability management (ALM) model using integrated chance constraints
This paper discusses and develops a Two Stage Integrated Chance Constraints Programming for the Employees Provident Fund Malaysia. The main aim is to manage, that is, balance assets and liabilities. Integrated Chance Constraints not only limit the event of underfunding but also the amount of underfunding. This paper includes the numerical illustration
Probing Newton's Constant on Vast Scales: DGP Gravity, Cosmic Acceleration and Large Scale Structure
The nature of the fuel that drives today's cosmic acceleration is an open and
tantalizing mystery. The braneworld theory of Dvali, Gabadadze, and Porrati
(DGP) provides a context where late-time acceleration is driven not by some
energy-momentum component (dark energy), but rather is the manifestation of the
excruciatingly slow leakage of gravity off our four-dimensional world into an
extra dimension. At the same time, DGP gravity alters the gravitational force
law in a specific and dramatic way at cosmologically accessible scales. We
derive the DGP gravitational force law in a cosmological setting for spherical
perturbations at subhorizon scales and compute the growth of large-scale
structure. We find that a residual repulsive force at large distances gives
rise to a suppression of the growth of density and velocity perturbations.
Explaining the cosmic acceleration in this framework leads to a present day
fluctuation power spectrum normalization sigma_8 <= 0.8 at about the two-sigma
level, in contrast with observations. We discuss further theoretical work
necessary to go beyond our approximations to confirm these results.Comment: 21 pages, 3 figures. References adde
Portfolio optimisation models and properties of return distributions
Mean-risk models have been widely used in portfolio optimisation. However, such models may
produce portfolios that are dominated with respect to second order stochastic dominance and therefore not
optimal for rational and risk-averse investors. This paper considers the problem of constructing a portfolio
which is nondominated with respect to second order stochastic dominance and whose return distribution
has specified desirable properties. The problem is multi-objective and is transformed into a single
objective problem by using the reference point method, in which target levels, known as aspiration points,
are specified for the objective function values. A model is proposed in which the aspiration points relate to
ordered return outcomes of the portfolio return. The model is extended by additionally specifying
reservation points, which act pre-emptively in the optimisation. The theoretical properties of the models
are studied. The performance of the models on real data drawn from the Hang Seng index is also
investigated
Nonequilibrium Langevin dynamics: a demonstration study of shear flow fluctuations in a simple fluid
The present study is based on a recent success of the second-order stochastic
fluctuation theory in describing time autocorrelations of equilibrium and
nonequilibrium physical systems. In particular, it was shown to yield values of
the related deterministic parameters of the Langevin equation for a Couette
flow in a microscopic Molecular Dynamics model of a simple fluid. In this paper
we find all the remaining constants of the stochastic dynamics, which is then
numerically simulated and directly compared with the original physical system.
By using these data, we study in detail the accuracy and precision of a
second-order Langevin model for nonequilibrium physical systems, theoretically
and computationally. In addition, an intriguing relation is found between an
applied external force and cumulants of the resulting flow fluctuations. This
is characterized by a linear dependence of athermal cumulant ratio, a new
quantity introduced here
Pilot Wave model that includes creation and annihilation of particles
The purpose of this paper is to come up with a Pilot Wave model of quantum
field theory that incorporates particle creation and annihilation without
sacrificing determinism. This has been previously attempted in an article by
the same author titled "Incorporating particle creation and annihilation in
Pilot Wave model", in a much less satisfactory way. In this paper I would like
to "clean up" some of the things. In particular, I would like to get rid of a
very unnatural concept of "visibility" of particles, which makes the model much
simpler. On the other hand, I would like to add a mechanism for decoherence,
which was absent in the previous version.Comment: 9 pages, no figure
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