Effects of the Generalized Uncertainty Principle on the Inflation Parameters

We investigate the effects of the generalized uncertainty principle on the inflationary dynamics of the early universe in both standard and braneworld viewpoint. We choose the Randall-Sundrum II model as our underlying braneworld scenario. We find that the quantum gravitational effects lead to a spectral index which is not scale invariant. Also, the amplitude of density fluctuations is reduced by increasing the strength of quantum gravitational corrections. However, the tensor-to-scalar ratio increases by incorporation of these quantum gravity effects. We outline possible manifestations of these quantum gravity effects in the recent and future observations.Comment: 11 pages, revised version with new references, Accepted for publication in IJMP

Microscopic calculation of 6Li elastic and transition form factors

Variational Monte Carlo wave functions, obtained from a realistic Hamiltonian consisting of the Argonne v18 two-nucleon and Urbana-IX three-nucleon interactions, are used to calculate the 6Li ground-state longitudinal and transverse form factors as well as transition form factors to the first four excited states. The charge and current operators include one- and two-body components, leading terms of which are constructed consistently with the two-nucleon interaction. The calculated form factors and radiative widths are in good agreement with available experimental data.Comment: 9 pages, 2 figures, REVTeX, submitted to Physical Review Letters, with updated introduction and reference

A proposed new policy for planetary protection

A critical review of the present policy was conducted with emphasis on its application to future planetary exploration. The probable impact of recent data on the implementation of the present policy was also assessed. The existing policy and its implementation were found to: be excessive for certain missions (e.g., Voyager), neglect the contamination hazard posed by the bulk constituent organics of spacecraft, be ambiguous for certain missions (e.g., Pioneer Venus), and treat all extraterrestrial sample return missions alike. The major features of the proposed policy are planet/mission combinations, a qualitative top level statement, and implementation by exception rather than rule. The concept of planet/mission categories permits the imposition of requirements according to both biological interest in the target planet and the relative contamination hazard of the mission type

Assessment of the visibility impairment caused by the emissions from the proposed power plant at Boron, California

The current atmospheric conditions and visibility were modeled, and the effect of the power plant effluent was then added to determine its influence upon the prevailing visibility; the actual reduction in visibility being a function of meteorological conditions and observer-plume-target geometry. In the cases investigated, the perceptibility of a target was reduced by a minimum of 10 percent and a maximum of 100 percent. This significant visual impact would occur 40 days per year in the Edwards area with meteorological conditions such as to cause some visual impact 80 days per year

Viable tax constitutions

Taxation is only sustainable if the general public complies with it. This observation is uncontroversial with tax practitioners but has been ignored by the public finance tradition, which has interpreted tax constitutions as binding contracts by which the power to tax is irretrievably conferred by individuals to government, which can then levy any tax it chooses. However, in the absence of an outside party enforcing contracts between members of a group, no arrangement within groups can be considered to be a binding contract, and therefore the power of tax must be sanctioned by individuals on an ongoing basis. In this paper we offer, for the first time, a theoretical analysis of this fundamental compliance problem associated with taxation, obtaining predictions that in some cases point to a re-interptretation of the theoretical constructions of the public finance tradition while in others call them into question

Cosmic antiprotons as a probe for supersymmetric dark matter?

The flux of cosmic ray antiprotons from neutralino annihilations in the galactic halo is computed for a large sample of models in the MSSM (the Minimal Supersymmetric extension of the Standard Model). We also revisit the problem of estimating the background of low-energy cosmic ray induced secondary antiprotons, taking into account their subsequent interactions (and energy loss) and the presence of nuclei in the interstellar matter. We consider a two-zone diffusion model, with and without a galactic wind. We find that, given the uncertainties in the background predictions, there is no need for a primary (exotic) component to explain present data. However, allowing for a signal by playing with the uncertainties in the background estimate, we discuss the characteristic features of the supersymmetric models which give a satisfactory description of the data. We point out that in some cases the optimal kinetic energy to search for a signal from supersymmetric dark matter is above several GeV, rather than the traditional sub-GeV region. The large astrophysical uncertainties involved do not, one the other hand, allow the exclusion of any of the MSSM models we consider, on the basis of data. We present besides numerical results also convenient parameterizations of the antiproton yields of all `basic' two-body final states. We also give examples of the yield and differential energy spectrum for a set of supersymmetric models with high rates. We also remark that it is difficult to put a limit on the antiproton lifetime from present measurements, since the injection of antiprotons from neutralino annihilation can compensate the loss from decay.Comment: 22 pages, 11 figures, uses emulateapj.st

W/Z Bremsstrahlung as the Dominant Annihilation Channel for Dark Matter, Revisited

We revisit the calculation of electroweak bremsstrahlung contributions to dark matter annihilation. Dark matter annihilation to leptons is necessarily accompanied by electroweak radiative corrections, in which a $W$ or $Z$ boson is also radiated. Significantly, while many dark matter models feature a helicity suppressed annihilation rate to fermions, bremsstrahlung process can remove this helicity suppression such that the branching ratios Br($\ell \nu W$), Br($\ell^+\ell^-Z$), and Br($\bar\nu \nu Z$) dominate over Br($\ell^+\ell^-$) and Br($\bar\nu \nu$). We find this is most significant in the limit where the dark matter mass is nearly degenerate with the mass of the boson which mediates the annihilation process. Electroweak bremsstrahlung has important phenomenological consequences both for the magnitude of the total dark matter annihilation cross section and for the character of the astrophysical signals for indirect detection. Given that the $W$ and $Z$ gauge bosons decay dominantly via hadronic channels, it is impossible to produce final state leptons without accompanying protons, antiprotons, and gamma rays.Comment: 8 pages, 6 figures; replaced to match published versio

The Abundance of New Kind of Dark Matter Structures

A new kind of dark matter structures, ultracompact minihalos (UCMHs) was proposed recently. They would be formed during the radiation dominated epoch if the large density perturbations are existent. Moreover, if the dark matter is made up of weakly interacting massive particles, the UCMHs can have effect on cosmological evolution because of the high density and dark matter annihilation within them. In this paper, one new parameter is introduced to consider the contributions of UCMHs due to the dark matter annihilation to the evolution of cosmology, and we use the current and future CMB observations to obtain the constraint on the new parameter and then the abundance of UCMHs. The final results are applicable for a wider range of dark matter parametersComment: 4 pages, 1 tabl

Evaluating the Impact of Maternal Vitamin D Supplementation on Sow Performance, Serum Vitamin Metabolites, Neonatal Muscle and Bone Characteristics, and Subsequent Pre-weaning Pig Performance

A total of 56 gestating sows (PIC 1050; 35-d post-insemination) were used in a 30-d trial to determine the serum 25(OH)D3 response to increasing concentrations of vitamins D3. At initiation, sows were randomly allotted to 1 of 7 dietary vitamin D3 treatments (91, 363, 726, 1,451, 2,903, 5,806, or 11,612 IU of vitamin D3/lb of complete diet) with 8 sows per treatment. All sows were fed 5.5 lb daily at 0800. Increasing vitamin D3 increased (quadratic; P \u3c 0.001) serum 25(OH)D3 with the response depicted by the following prediction equation: Serum 25(OH)D3, ng/mL = 35.1746 + (0.002353 × dietary vitamin D3, IU/d) - (0.0000000156 × dietary vitamin D3, IU/d2) In Exp. 2, 112 sows and their litters were used to determine the effects of supplemented vitamin D on sow performance, subsequent pre-weaning pig performance, neonatal pig bone and muscle characteristics, and serum vitamin metabolites. Sows were allotted to 1 of 4 dietary regimens: 1) low vitamin D3 (363 IU/lb); 2) medium vitamin D3 (907 IU/lb); 3) high vitamin D3 (4,354 IU/lb); or 4) 23 μg 25(OH)D3/lb (Hy-D, DSM Nutritional Products Inc, Parsippany, NJ), which were fed throughout gestation and lactation. There were 25 to 27 sows per treatment. Overall, increasing maternal vitamin D3 increased (linear, P = 0.001) serum 25 (OH)D3 of sows on d 100 of gestation, at farrowing, and at weaning. Also increasing vitamin D3 in diets fed to sows increased piglet serum 25(OH)D3 at birth (linear, P = 0.001) and weaning (quadratic, P = 0.033). Sows fed 25(OH)D3 had greater (P \u3c 0.001) serum 25(OH)D3 concentrations on d 100 of gestation, at farrowing, and at weaning compared to sows fed the low or medium concentration of vitamin D3; however, they were reduced (P \u3c 0.004) compared to the serum 25(OH)D3 concentrations of sows fed the high concentration of vitamin D3 on the same collection days. Piglets from sows fed 25(OH)D3 had greater serum 25(OH)D3 compared to piglets from sows fed the low and medium concentration of vitamin D3; however, at weaning, serum 25(OH)D3 concentrations were only greater compared to the low concentration of vitamin D3. Also, piglets from sows fed the high concentration of vitamin D had greater (P = 0.011) serum 25(OH)D3 concentration at birth and at weaning, compared to piglets from sows fed 25(OH)D3. Maternal performance, litter characteristics, neonatal bone ash content, and neonatal muscle fiber characteristics were largely unaffected by the maternal vitamin D regimen. Overall, vitamin D3 and 25(OH)D3 both appear to be useful at increasing serum 25(OH) D3 concentrations, but more vitamin D3 (on an IU basis) is needed to achieve similar serum 25(OH)D3 responses compared to feeding 25(OH)D3. Interestingly, sows fed 25(OH)D3 in lactation had less vitamin D transport to the pig than sows fed medium and high concentrations of vitamin D3 suggesting that vitamin D3 is still a more useful metabolite for milk transfer of the vitamin. Due to the lack of impact of maternal vitamin D regimen on sow or pre-weaned pig performance, and neonatal muscle characteristics, more research examining the impact of vitamin D on immune function and novel biological processes is needed to assess the value of vitamin D supplementation strategies in pigs