From super-charged nuclei to massive nuclear density cores

Due to $e^+e^-$-pair production in the field of supercritical $(Z \gg Z_{cr}\approx 170$) 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 $Ze^3 \gg 1$ the electron shell penetrates inside the nucleus and almost completely screens its charge. Inside such nucleus the potential takes a constant value equal to $V_0=-(3\pi^2 n_p)^{1/3} \sim -2m_{\pi}c^2$, and super-charged nucleus represents an electrically neutral plasma consisting of $e,p$ and $n$. Near the edge of the nucleus a transition layer exists with a width $\lambda \approx \alpha^{-1/2} \hbar/m_{\pi} c\sim 15$ fm, which is independent of $Z (\hbar/m_{\pi} c \ll \lambda \ll \hbar/m_e c)$. 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 $A \approx (m_{Planck}/m_n)\sim 10^{57}$. 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 $E\sim m^2_{\pi} c^3/e\hbar$ 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

Lessons from the Transition Economies: Putting the Success Stories of the Postcommunist World into a Broader Perspective

Why many transition economies succeeded by pursuing policies that are so different from the radical economic liberalization (shock therapy) that is normally credited for the economic success of central European countries? First, optimal policies are context dependent, they are specific for each stage of development and what worked in Slovenia cannot be expected to work in Mongolia. Second, even for countries at the same level of development, reforms needed to stimulate growth are different; they depend on the previous history and on the path chosen. The reduction of government expenditure as a share of GDP did not undermine significantly the institutional capacity of the state in China, but in Russia and other CIS states it turned out to be ruinous. It is the growth diagnostics that should reveal the missing ingredient for economic growth. Finally, and most important, introducing this .missing ingredient. should not result in the destruction of other preconditions for growth. The art of the policymaker is to create markets without causing the government failure, as happened in many CIS countries.transition, growth diagnostics, path dependence

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

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

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

Is Chinese variety of capitalism really unique?

The formal comparison of similarities and differences of Chinese and Western economic models misses the most important point. The uniqueness of China is that it looks very much like a developed country today in terms of institutional capacity of the state, even though it is a developing country according to GDP per capita. Indeed, China should be compared with developing countries today or developed countries a hundred years ago, when their GDP was at the current Chinese level, and this comparison is very much in favour of China. Institutional capacity of the state, according to a narrow definition, is the ability of the government to enforce laws and regulations. While there are a lot of subjective indices (corruption, rule of law, government effectiveness, etc.) that are supposed to measure state institutional capacity, many researchers do not think they help to explain economic performance and instead consider them biased. The natural objective measures of state institutional capacity are the murder rate (noncompliance with the state’s monopoly on violence4) and the shadow economy (non-compliance with the economic regulations). China is rather unique on both measures – one of the lowest indicators in the developing world comparable to developed countries.Chinese economic model,uniqueness, institutional capacity

To devalue or not to devalue? How East European countries responded to the outflow of capital in 1997-99 and in 2008-09

If there is a negative terms of trade or financial shock leading to the deterioration in the balance of payments, there are two basic options for a country that has limited foreign exchange reserves. First, a country can maintain a fixed exchange rate (or even a currency board) and wait until the reduction of foreign exchange reserves leads to the reduction of money supply: this will drive domestic prices down and stimulate exports, raise interest rates and stimulate the inflow of capital, and finally will correct the balance of payments. Second, the country can allow the devaluation of national currency – flexible exchange rate will automatically bring the balance of payments back into the equilibrium. Because national prices are less flexible than exchange rates, the first type of adjustment is associated with the greater reduction of output. The empirical evidence on East European countries and other transition economies for 1998-99 period (outflow of capital after the 1997 Asian and 1998 Russian currency crises and slowdown of output growth rates) suggests that the second type of policy response (devaluation) was associated with smaller loss of output than the first type (monetary contraction). 2008-09 developments provide additional evidence for this hypothesis.Devaluation, capital account shocks, fixed and flexible exchange rates, macroeconomic response to shocks