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    From super-charged nuclei to massive nuclear density cores

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    Due to e+ee^+e^--pair production in the field of supercritical (ZZcr170(Z \gg Z_{cr}\approx 170 ) nucleus an electron shell, created out of the vacuum, is formed. The distribution of the vacuum charge in this shell has been determined for super-charged nuclei Ze^3 \ga 1 within the framework of the Thomas-Fermi equation generalized to the relativistic case. For Ze31Ze^3 \gg 1 the electron shell penetrates inside the nucleus and almost completely screens its charge. Inside such nucleus the potential takes a constant value equal to V0=(3π2np)1/32mπc2V_0=-(3\pi^2 n_p)^{1/3} \sim -2m_{\pi}c^2, and super-charged nucleus represents an electrically neutral plasma consisting of e,pe,p and nn. Near the edge of the nucleus a transition layer exists with a width λα1/2/mπc15\lambda \approx \alpha^{-1/2} \hbar/m_{\pi} c\sim 15 fm, which is independent of Z(/mπcλ/mec)Z (\hbar/m_{\pi} c \ll \lambda \ll \hbar/m_e c). The electric field and surface charge are concentrated in this layer. These results, obtained earlier for hypothetical superheavy nuclei with Z \sim A/2\la 10^4 \div 10^6, are extrapolated to massive nuclear density cores having a mass number A(mPlanck/mn)1057A \approx (m_{Planck}/m_n)\sim 10^{57}. The problem of the gravitational and electrodynamical stability of such objects is considered. It is shown that for A \ga 0.04 (Z/A)^{1/2}(m_{Planck}/m_n)^3 the Coulomb repulsion of protons, screened by relativistic electrons, can be balanced by gravitational forces. The overcritical electric fields Emπ2c3/eE\sim m^2_{\pi} c^3/e\hbar are present in the narrow transition layer near the core surface.Comment: To appear in the proceedings of the international conference "The Sun, the Stars, The Universe and General Relativity" in honor of Ya.B. Zeldovich 95th Anniversary, held in Minsk, Belarus on April 20-23, 2009. AIP Conf. Proc. Vol. 1205 (2010

    Mortality Crisis in Russia Revisited: Evidence from Cross-Regional Comparison

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    This paper provides evidence from cross-regional comparisons that the Russian mortality crisis (mortality rate increased from 1.0% to 1.6% in 1989-94 and stayed at a level of 1.4-1.6% thereafter) was caused mostly by stress factors (increased unemployment, labor turnover, migration, divorces, income inequalities), and by the increase in unnatural deaths (murders, suicides, accidents), but not so much by the increase in alcohol consumption (even though it also increased due to the same stress factors). Health infrastructure of a region had a positive impact on life expectancy only in regions with high income inequalities (large share of highest income group).MORTALITY CRISIS IN RUSSIA

    Development theories and development experience: half a century journey

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    This paper examines the impact that development theories have had on development policies, and the inverse impact of actual successes and failures in the global South on development thinking. It is argued that development thinking is at the cross-roads. Development theories in postwar period went through a full circle – from Big Push and ISI to neo-liberal Washington consensus to the understanding that neither the former, nor the later really works in engineering successful catch-up development. Meanwhile, economic miracles were manufactured in East Asia without much reliance on development thinking and theoretical background – just by experimentation of the strong hand politicians.Development theories, catch up growth, economic miracles, Washington consensus, import substitution, "Big push", export orientation