Classification of finite dimensional modules of singly atypical type over the Lie superalgebras sl(m/n)

We classify the finite dimensional indecomposable sl(m/n)-modules with at least a typical or singly atypical primitive weight. We do this classification not only for weight modules, but also for generalized weight modules. We obtain that such a generalized weight module is simply a module obtained by ``linking'' sub-quotient modules of generalized Kac-modules. By applying our results to sl(m/1), we have in fact completely classified all finite dimensional sl(m/1)-modules.Comment: 17 pages, Late

On the equilibrium of the magnetopause current layer

Magnetopause current layer equilibriu

On indecomposable modules over the Virasoro algebra

It is proved that an indecomposable Harish-Chandra module over the Virasoro algebra must be (i) a uniformly bounded module, or (ii) a module in Category $\cal O$, or (iii) a module in Category ${\cal O}^-$, or (iv) a module which contains the trivial module as one of its composition factors.Comment: 5 pages, Latex, to appear in Science in China

Re-analyzing the economic impact of a global bunker emissions charge

© 2018 Elsevier B.V. Regulating bunker emissions continues to be a challenging task, largely due to the lack of a globally coordinated scheme providing economic and political incentives to potential participating countries. This paper analyses the economic costs and benefits of imposing a global carbon tax on international bunker emissions by employing a computable general equilibrium model approach. Under the assumption of an emissions reduction of 5% below 2000 levels by 2020, we demonstrate that a global bunker emissions charge, on one hand, reduces trade volume and change trade patterns between countries and regions, while on the other hand, accelerates the adoption of energy-saving technologies and reallocates the supply of international transportation services throughout the world. The net economic impact, though negative on average, is modest compared to the benefits obtained from the emissions reduction. If revenues from a bunker emissions charge are properly distributed among countries and regions, the losses to disadvantaged countries are likely to be offset by the benefits to advantaged countries. This finding provides useful insights for policy-makers: a global bunker emissions charge could, in future, be an economically feasible strategy to reduce the increasing bunker emissions through the implementation requires more political effort and wisdom

Economic, social and environmental impacts of fuel subsidies: A revisit of Malaysia

© 2017 Elsevier Ltd Subsidizing energy has been widely used but is economically unfavorable. The Malaysian government has shown strong intention to reduce energy subsidies recently, but face challenges to prepare policy instruments to manage the impact. This study develops a Computable General Equilibrium (CGE) model with breakdown of households by income level to evaluate the potential impacts of removing energy subsidies on the Malaysian economy. It is shown that removing petroleum and gas subsidy would improve economic efficiency and increase GDP up to 0.65%. Budget deficit would be largely reduced after removing the petroleum subsidies, especially when the saved subsidy cost is not budgeted for other expenditure. Households would be worse off in most scenarios due to higher price level, but some compensation policy could make the lowest income group no worse than baseline, without harm the economy. The reduction in carbon emissions ranges 1.84–6.63% in different scenarios. The simulation results suggest Malaysia to completely remove all fuel subsidies and use the saved funding to cut budget deficit or spend on education, health and other service sector. It is also necessary to set a compensation scheme to minimize public resistance and make sure such scheme is affordable

Notes on Ghost Dark Energy

We study a phenomenological dark energy model which is rooted in the Veneziano ghost of QCD. In this dark energy model, the energy density of dark energy is proportional to Hubble parameter and the proportional coefficient is of the order $\Lambda^3_{QCD}$, where $\Lambda_{QCD}$ is the mass scale of QCD. The universe has a de Sitter phase at late time and begins to accelerate at redshift around $z_{acc}\sim0.6$. We also fit this model and give the constraints on model parameters, with current observational data including SnIa, BAO, CMB, BBN and Hubble parameter data. We find that the squared sound speed of the dark energy is negative, which may cause an instability. We also study the cosmological evolution of the dark energy with interaction with cold dark matter.Comment: 20 pages,10 figures,Correct some typos and add new reference