Low energy bounds on Poincare violation in causal set theory

In the causal set approach to quantum gravity, Poincar\'{e} symmetry is modified by swerving in spacetime, induced by the random lattice discretization of the space-time structure. The broken translational symmetry at short distances is argued to lead to a residual diffusion in momentum space, whereby a particle can acquire energy and momentum by drift along its mass shell and a system in equilibrium can spontaneously heat up. We consider bounds on the rate of momentum space diffusion coming from astrophysical molecular clouds, nuclear stability and cosmological neutrino background. We find that the strongest limits come from relic neutrinos, which we estimate to constrain the momentum space diffusion constant by $k < 10^{-61} {\rm GeV}^3$ for neutrinos with masses $m_\nu > 0.01 {\rm eV}$, improving the previously quoted bounds by roughly 17 orders of magnitude.Comment: Additional discussion about behavior of alpha particles in nuclei added. Version matches that accepted in PR

Institutional structures and processes for environmental planning and management of the peri-urban interface

Strategies are needed which deal not only with urban impacts but also with the transitional nature of activities in the zone, once urban impacts are felt. And there are strategies for rural activities to exploit their proximity to towns and cities. Yet these strategies must be matched to the limited capacities of the institutions available for formulating and implementing them if they are to be effective. Alternatively, institutions can be given new capacities or new relationships

Causal sets and conservation laws in tests of Lorentz symmetry

Many of the most important astrophysical tests of Lorentz symmetry also assume that energy-momentum of the observed particles is exactly conserved. In the causal set approach to quantum gravity a particular kind of Lorentz symmetry holds but energy-momentum conservation may be violated. We show that incorrectly assuming exact conservation can give rise to a spurious signal of Lorentz symmetry violation for a causal set. However, the size of this spurious signal is much smaller than can be currently detected and hence astrophysical Lorentz symmetry tests as currently performed are safe from causal set induced violations of energy-momentum conservation.Comment: 8 pages, matches version published in PR

On Recent Progress for the Stochastic Navier Stokes Equations

We give an overview of the ideas central to some recent developments in the ergodic theory of the stochastically forced Navier Stokes equations and other dissipative stochastic partial differential equations. Since our desire is to make the core ideas clear, we will mostly work with a specific example: the stochastically forced Navier Stokes equations. To further clarify ideas, we will also examine in detail a toy problem. A few general theorems are given. Spatial regularity, ergodicity, exponential mixing, coupling for a SPDE, and hypoellipticity are all discussed.Comment: Corrected version of Journees Equations aux derivees partielles paper(June 2003). Original at http://www.math.sciences.univ-nantes.fr/edpa/2003

Regional young child poverty in 2008: rural Midwest sees increased poverty, while urban Northeast rates decrease

In 2008, America\u27s recession affected poverty rates for children under age 6 unevenly, with rates in the rural Midwest rising significantly, while rates in northeastern central cities fell slightly. And in the rural South, where more than 30 percent of young children are poor, poverty rates for young children persisted at a very high rate. This is an analysis of American Community Survey data released by the U.S. Census Bureau

Child tax credit expansion increases number of families eligible for a refund

The analysis shows that more than 500,000 rural families, or almost 9 percent of rural families, will become newly eligible for the Child Tax Credit under the expansion included in the American Recovery and Reinvestment Act. Within these families are an estimated 900,000 rural children. The proportion of urban families benefiting from the expanded Child Tax Credit is slightly lower than in rural areas, but only 5 percent of suburban families are newly eligible for the credit

Forty-three percent of eligible rural families can claim a larger credit with EITC expansion

This policy brief on the changes to the Earned Income Tax Credit in the ARRA also shows that families with three or more children and married couples will receive an increased refund under these new EITC rules for tax years 2009 and 2010. Many families in urban and suburban communities will also see increased benefits under these new provisions

Seventy-eight percent of working rural families to receive full Making Work Pay tax credit

The Making Work Pay Tax Credit provides eligible U.S. workers with additional money in each paycheck throughout the year. The fact sheet shows that 78 percent of rural working families will receive the full amount of the credit, while an additional 10 percent of families will receive a partial credit due to low earnings or high earnings. These tax credits, along with the expansion to the Child Tax Credit, are an important financial boost to families in rural America, particularly low-income working families