1,297 research outputs found
Kardar-Parisi-Zhang asymptotics for the two-dimensional noisy Kuramoto-Sivashinsky equation
We study numerically the Kuramoto-Sivashinsky (KS) equation forced by
external white noise in two space dimensions, that is a generic model for e.g.
surface kinetic roughening in the presence of morphological instabilities.
Large scale simulations using a pseudospectral numerical scheme allow us to
retrieve Kardar-Parisi-Zhang (KPZ) scaling as the asymptotic state of the
system, as in the 1D case. However, this is only the case for sufficiently
large values of the coupling and/or system size, so that previous conclusions
on non-KPZ asymptotics are demonstrated as finite size effects. Crossover
effects are comparatively stronger for the 2D case than for the 1D system.Comment: 5 pages, 3 figures; supplemental material available at journal web
page and/or on reques
Analytical approximation for the sphere-sphere Coulomb potential
A simple analytical expression, which closely approximates the Coulomb
potential between two uniformly charged spheres, is presented. This expression
can be used in the optical potential semiclassical analyses which require that
the interaction be analytic on and near the real r-axis.Comment: 4 pages including 3 figures and 1 tabl
The carbon budget of crustal reworking during continental collision: Clues from nanorocks and fluid inclusions
The source of volatiles in the continental crust is a long-standing issue. In addition to controlling the amount of melt generated during anatexis, H2O and CO2 budgets of the middle and lower siliciclastic crust are also of great importance for carbonate precipitation, ore concentration, orogenic degassing and carbon storage. Here we focus on two case studies of partially melted metamorphic rocks of crustal affinity– the Ivrea Zone in the Western Alps (0.8 GPa) and the Central Maine Terrane (1.8 GPa), USA. These terrains contain fluid inclusions and carbonbearing nanogranitoids (former melt inclusions) from which the H2O and CO2 content has been estimated via in-situ analyses. Thermodynamic modelling is used to quantify the amount of internally derived, mineral-bound
bulk rock CO2 necessary to reproduce the volatile contents of these melt inclusions. The minimum amount of bulk rock CO2 present at peak metamorphic conditions is estimated at 400 ppm for the Ivrea Zone and 3000 ppm for the Central Maine Terrane. This suggests that the flux of carbon associated with the burial of siliciclastic sediments in the lower crust during the Phanerozoic is 0.2–4.4 Mt. C/yr. These values, as well as the nature of the source of the deep crustal carbon might have changed with time, with periods dominated by internal reworking rather than external inputs. The protracted growth and differentiation of the continental crust through the reworking of supracrustal materials in continental collision settings is a key element of carbon storage processes. The stability of the continental crust through time provides an ultimate, long-lasting reservoir of carbon
Refractive elastic scattering of carbon and oxygen nuclei: The mean field analysis and Airy structures
The experimental data on the OC and OC elastic
scatterings and their optical model analysis are presented. Detailed and
complete elastic angular distributions have been measured at the Strasbourg
Vivitron accelerator at several energies covering the energy range between 5
and 10 MeV per nucleon. The elastic scattering angular distributions show the
usual diffraction pattern and also, at larger angles, refractive effects in the
form of nuclear rainbow and associated Airy structures. The optical model
analysis unambiguously shows the evolution of the refractive scattering
pattern. The observed structure, namely the Airy minima, can be consistently
described by a nucleus-nucleus potential with a deep real part and a weakly
absorptive imaginary part. The difference in absorption in the two systems is
explained by an increased imaginary (mostly surface) part of the potential in
the OC system. The relation between the obtained potentials and
those reported for the symmetrical OO and CC
systems is drawn.Comment: 10 pages, 9 figures, Phys. rev. C in pres
Regional inequalities and transnational solidarity in the European Union
Amid the eurocrisis, scholars and policy makers sought to establish an EU-wide layer of social policy, aiming to ensure common standards through the EU and to provide a degree of common social protection. While public support for European social policy has been extensively studied, we don't know how regional (i.e., subnational) inequalities relate to preferences for European social policy. We analyse the effect of regional differences in socio-economic and institutional contexts on public preferences for European social policy in general and support for European unemployment insurance in particular. Combining original survey data collected in 2018 in 12 European countries with regional-level economic and political indicators, we find that regional-level self-interest impacts individual preferences but that the effect is not always clear-cut. Contrary to expectations, people in richer regions are more supportive of EU social policy than people in poorer regions, while citizens of politically more autonomous regions tend to have a generally more positive view of EU social policy. A conjoint experiment on support for different policy variants of European unemployment insurance sheds light on these counterintuitive findings: Citizens in richer regions are indeed more supportive of EU-level social policy, but only when it has limited redistributive implications and instead affects standards; conversely citizens in poorer regions are willing to forego their opposition to EU social policy for redistributive programs
Regional inequalities and transnational solidarity in the European Union
Amid the eurocrisis, scholars and policy makers sought to establish an EU-wide layer of social policy, aiming to ensure common standards through the EU and to
provide a degree of common social protection. While public support for European social policy has been extensively studied, we don’t know how regional (i.e.,
subnational) inequalities relate to preferences for European social policy. We analyse the effect of regional differences in socio-economic and institutional contexts on
public preferences for European social policy in general and support for European unemployment insurance in particular. Combining original survey data collected in
2018 in 12 European countries with regional-level economic and political indicators, we find that regional-level self-interest impacts individual preferences but that
the effect is not always clear-cut. Contrary to expectations, people in richer regions are more supportive of EU social policy than people in poorer regions, while
citizens of politically more autonomous regions tend to have a generally more positive view of EU social policy. A conjoint experiment on support for different policy
variants of European unemployment insurance sheds light on these counterintuitive findings: Citizens in richer regions are indeed more supportive of EU-level social
policy, but only when it has limited redistributive implications and instead affects standards; conversely citizens in poorer regions are willing to forego their op-
position to EU social policy for redistributive programs
Not so far east? The impact of Central-Eastern European imports on the Brexit referendum
We explore the effect of the UK’s economic links with Central-Eastern Europe and China in the case of the Brexit referendum. First, we replicate and independently verify the Colantone and Stanig findings (2018a) on the effect of globalization on Brexit. Then, we extend their original analysis and demonstrate that although both Chinese and Central-Eastern European imports were significant causal determinants of the referendum’s outcome, exposure to Central-Eastern European imports was up to three times more important than exposure to Chinese imports. This may be due to cultural correlates of trade. Our analysis reveals that differences in media coverage between Central-Eastern European and Chinese economic news, as well as migrant population shares from these two regions, might have played a decisive role. Overall, the article also suggests that the import-shock method, as currently applied in the literature, is ill-suited to compare shocks with diverse origins
State of the art on Neuropterida of Sicily and Malta
Sicily, the largest Mediterranean island, is surrounded by many small islands (Aeolian Islands, Ustica, Aegadian Islands, Pantelleria, Linosa, Lampedusa, Maltese Islands), some of which forming archipelagoes. The authors, after a historical sketch of the research on Neuropterida in Sicily (sensu lato), analyze the biodiversity of the area, highlighting the species richness and providing an up-to-date check-list. The lack of knowledge on some of the most paradigmatic communities of Neuropterida is discussed in relation to their various habitats. The distributional patterns of Sicilian Neuropterida are interpreted in order to obtain a biogeographical characterization of the area. It is confirmed that the location of Sicily and its surrounding islands forms a bridge between north and south and a door from the W Mediterranean region to the oriental Mediterranean basi
Self-tuning of the cosmological constant
Here, I discuss the cosmological constant (CC) problems, in particular paying
attention to the vanishing cosmological constant. There are three cosmological
constant problems in particle physics. Hawking's idea of calculating the
probability amplitude for our Universe is peaked at CC = 0 which I try to
obtain after the initial inflationary period using a self-tuning model. I
review what has been discussed on the Hawking type calculation, and present a
(probably) correct way to calculate the amplitude, and show that the
Kim-Kyae-Lee self-tuning model allows a finite range of parameters for the CC =
0 to have a singularly large probability, approached from the AdS side.Comment: 12 pages with 8 figure
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