Black Markets for Currency, Hoarding Activity and Policy Reforms

In the former Soviet Union and throughout Eastern Europe, black-market exchange rates and second-economy prices often are interpreted by policy-makers as indicative of post-reform levels. However, these exchange rates and prices can provide highly-biased signals for policy setting. These biases are especially important when exchange rates fixed on the basis of these signals are expected to play a nominal anchor role during stabilizations. This paper traces the paths and biases in black-market exchange rates, second-economy prices, hoarding stocks, and privately-held dollars balances after policy-initiatives or other changes in the economic environment are implemented. The stimuli studied are official exchange-rate adjustments, price reforms, foreign-aid packages, altered risks of monetary confiscation or currency reforms, and goods-supply related initiatives. We provide the conditions under which announcements of reform lead short-run prices or exchange rates to overshoot or to undershoot their long-run equilibrium levels

Internal Currency Markets and Production in the Soviet Union

Changes in macroeconomic and microeconomic policies may yield surprising results when applied within an economy in the process of economic reform. This paper examines the effectiveness of policy instruments introduced as components of partial economic-reform programs, as in the Soviet Union. It is shown that the market power of producers in domestic industries and the design of currency auctions or interbank markets are key determinants, respectively, of the magnitude and direction of the enterprise responses to policy changes and external shocks. Policy-induced shifts in production and the hard currency allocation decisions of producers are determined. These optimizing choices have implications for: the supply of goods available for domestic consumption; domestic goods prices; the supply of hard currency to internal auctions or interbank markets; the free internal price of foreign exchange; export volumes; and the overall trade balance

Moscow Black Markets and Official Markets for Foreign Exchange: How Much Flexibility in Flexible Rates?

enterprises ; financial market ; banks ; policy making

Exchange-rate Unification with Black Market Leakages: Russia 1992

exchange rate ; financial market

Blak-Markets for Currency, Hoarding Activity and Policy Reforms

financial market ; black market

Investment in Manufacturing, Exchange-Rate and External Exposure

investments ; exchange rate

Departures from the Ruble Zone: The Implications of Adopting Independent Currencies

monetary theory

Nonperturbative bound on high multiplicity cross sections in phi^4_3 from lattice simulation

We have looked for evidence of large cross sections at large multiplicities in weakly coupled scalar field theory in three dimensions. We use spectral function sum rules to derive bounds on total cross sections where the sum can be expresed in terms of a quantity which can be measured by Monte Carlo simulation in Euclidean space. We find that high multiplicity cross sections remain small for energies and multiplicities for which large effects had been suggested.Comment: 23 pages, revtex, seven eps figures revised version: typos corrected, some rewriting of discusion, same resul

Reconstruction of Black Hole Metric Perturbations from Weyl Curvature

Perturbation theory of rotating black holes is usually described in terms of Weyl scalars $\psi_4$ and $\psi_0$, which each satisfy Teukolsky's complex master wave equation and respectively represent outgoing and ingoing radiation. On the other hand metric perturbations of a Kerr hole can be described in terms of (Hertz-like) potentials $\Psi$ in outgoing or ingoing {\it radiation gauges}. In this paper we relate these potentials to what one actually computes in perturbation theory, i.e $\psi_4$ and $\psi_0$. We explicitly construct these relations in the nonrotating limit, preparatory to devising a corresponding approach for building up the perturbed spacetime of a rotating black hole. We discuss the application of our procedure to second order perturbation theory and to the study of radiation reaction effects for a particle orbiting a massive black hole.Comment: 6 Pages, Revtex

Gravitational radiation from a particle in circular orbit around a black hole. V. Black-hole absorption and tail corrections

A particle of mass $\mu$ moves on a circular orbit of a nonrotating black hole of mass $M$. Under the restrictions $\mu/M \ll 1$ and $v \ll 1$, where $v$ is the orbital velocity, we consider the gravitational waves emitted by such a binary system. We calculate $\dot{E}$, the rate at which the gravitational waves remove energy from the system. The total energy loss is given by $\dot{E} = \dot{E}^\infty + \dot{E}^H$, where $\dot{E}^\infty$ denotes that part of the gravitational-wave energy which is carried off to infinity, while $\dot{E}^H$ denotes the part which is absorbed by the black hole. We show that the black-hole absorption is a small effect: $\dot{E}^H/\dot{E} \simeq v^8$. We also compare the wave generation formalism which derives from perturbation theory to the post-Newtonian formalism of Blanchet and Damour. Among other things we consider the corrections to the asymptotic gravitational-wave field which are due to wave-propagation (tail) effects.Comment: ReVTeX, 17 page