Nonequilibrium Steady State Driven by a Nonlinear Drift Force

We investigate the properties of the nonequilibrium steady state for the stochastic system driven by a nonlinear drift force and influenced by noises which are not identically and independently distributed. The nonequilibrium steady state (NESS) current results from a residual part of the drift force which is not cancelled by the diffusive action of noises. From our previous study for the linear drift force the NESS current was found to circulate on the equiprobability surface with the maximum at a stable fixed point of the drift force. For the nonlinear drift force, we use the perturbation theory with respect to the cubic and quartic coefficients of the drift force. We find an interesting potential landscape picture where the probability maximum shifts from the fixed point of the drift force and, furthermore, the NESS current has a nontrivial circulation which flows off the equiprobability surface and has various centers not located at the probability maximum. The theoretical result is well confirmed by the computer simulation.Comment: 10 pages, 4 figure

High inflation: causes and consequences

Using evidence from seven hyperinflationary episodes in four Latin American countries in the second half of the 1980s, John Rogers and Ping Wang examine the causes and consequences of high inflation. The article emphasizes four issues: the welfare costs of inflation and real costs of stabilization, the common features of the chronically high inflations experienced in Latin American countries, the main causes of high inflation, and the widely different outcomes of several stabilization programs. ; Rogers and Wang find that the welfare costs of even moderate periods of inflation may not be negligible, whereas the adverse macroeconomic effects of stabilization efforts are mostly temporary. The authors show that the spiral-like adjustment of the government budget and monetary growth may result in a high-inflation trap. The main causes of chronically high inflation include continuous fiscal-monetary extension, productivity slowdown, systematic undervaluation of the domestic currency, and diminished credibility of anti-inflation policies. Successful stabilization, in essence, results from budgetary adjustment, market liberalization, and the adoption of a nominal anchor (such as the nominal exchange rate), all of which ensure credibility of the public authorities.Inflation (Finance)

The Timing of Childbearing among Heterogeneous Women in Dynamic General Equilibrium

We develop a tractable framework with a fully specified dynamic process of demographic and labor decisions over an individual female's life span to determine the timing of childbearing. Fertility affects women's behavior through three channels: its tradeoff with leisure, its interactions with human capital investment, and its cost in terms of lost market productivity. Instead of numerically solving a discrete-time version of the model, we propose an alternative solution technique that provides analytic, closed-form solutions for the continuous-time dynamic optimization problem with (discrete) time-line variables. The analytic results indicate that (i) increased impatience has an ambiguous effect on childbearing timing; (ii) the age at first birth rises at an increasing rate with the productivity loss from children; and (iii) women of greater ability have births at later ages and are more sensitive to parameter changes. Calibration exercises suggest that focusing on the median female's response to changes in the preference, cost, and technology parameters fails to capture their important distributional effects.

Generating entanglement between microwave photons and qubits in multiple cavities coupled by a superconducting qutrit

We discuss how to generate entangled coherent states of four \textrm{microwave} resonators \textrm{(a.k.a. cavities)} coupled by a superconducting qubit. We also show \textrm{that} a GHZ state of four superconducting qubits embedded in four different resonators \textrm{can be created with this scheme}. In principle, \textrm{the proposed method} can be extended to create an entangled coherent state of $n$ resonators and to prepare a Greenberger-Horne-Zeilinger (GHZ) state of $n$ qubits distributed over $n$ cavities in a quantum network. In addition, it is noted that four resonators coupled by a coupler qubit may be used as a basic circuit block to build a two-dimensional quantum network, which is useful for scalable quantum information processing.Comment: 13 pages, 7 figure

Extracting and Stabilizing the Unstable State of Hysteresis Loop

A novel perturbation method for the stabilization of unstable intermediate states of hysteresis loop (i.e. S-shaped curve) is proposed. This method only needs output signals of the system to construct the perturbation form without delay-coordinate embedding technique, it is more practical for real-world systems. Stabilizing and tracking the unstable intermediate branch are demonstrated through the examples of a bistable laser system and delay feedback system. All the numerical results are obtained by simulating each of the real experimential conditions.Comment: 6 pages, REVTEX, 4 ps figure