The monetary origins of the financial and economic crisis

Abstract The monetary policy, especially the American one, can be blamed for the remote role (2002-2004) it played in the creation of the speculative bubble which led to a financial crisis. It also has a part of the responsibility through its restrictive direction during the 2004-2006 period; this time, a direction shared by other central banks. Finally, it is more immediately involved through its lack of clear-sightedness and responsiveness in the first months of the recession.Economic crisis, Financial crisis, Monetary Policy, Taylor Rule,Taylor gap, Interest Term Spread, Recession

Finite element method analysis of band gap and transmission of two-dimensional metallic photonic crystals at terahertz frequencies

Photonic band gap and transmission characteristics of 2D metallic photonic crystals at THz frequencies have been investigated using finite element method (FEM). Photonic crystals composed of metallic rods in air, in square and triangular lattice arrangements, are considered for transverse electric and transverse magnetic polarizations. The modes and band gap characteristics of metallic photonic crystal structure are investigated by solving the eigenvalue problem over a unit cell of the lattice using periodic boundary conditions. A photonic band gap diagram of dielectric photonic crystal in square lattice array is also considered and compared with well-known plane wave expansion results verifying our FEM approach. The photonic band gap designs for both dielectric and metallic photonic crystals are consistent with previous studies obtained by different methods. Perfect match is obtained between photonic band gap diagrams and transmission spectra of corresponding lattice structure

Passively mode-locked semiconductor lasers and their applications

In this paper we present some characterizations of passively mode-locked semiconductor lasers. These lasers are multimode and they exhibit a modulation of their output power even though they are DC-biased. The modulation frequency corresponds to their free-spectral range. We demonstrate their potential: for generation of ultra-fast modulation for THz wave generation at room temperature without any direct modulations applied, in the radio frequency range they synchronise their modulation to the bit-rate of an incoming signal used for clock extraction. Therefore these devices can be used for all-optical clock recovery

Terahertz wave generation from a dc-biased multimode laser

We present results achieved in the generation of terahertz wave by a semiconductor laser. It is a Fabry–Pérot based device with shallow grooves implemented on its p-side to engineer the longitudinal mode spectrum. The laser is dc-biased and temperature controlled at 298 K. The main two modes are separated by 3 nm at 1550 nm with a side-mode-suppression ratio of 25 dB. Using a frequency resolved optical gating, evidence of mode beating at 373 GHz is observed. With a bolometer interfaced to a Fourier transform interferometer, the second harmonic signal is measured at 690 GHz

Topography of (exo)planets

Current technology is not able to map the topography of rocky exoplanets, simply because the objects are too faint and far away to resolve them. Nevertheless, indirect effect of topography should be soon observable thanks to photometry techniques, and the possibility of detecting specular reflections. In addition, topography may have a strong effect on Earth-like exoplanet climates because oceans and mountains affect the distribution of clouds \citep{Houze2012}. Also topography is critical for evaluating surface habitability \citep{Dohm2015}. We propose here a general statistical theory to describe and generate realistic synthetic topographies of rocky exoplanetary bodies. In the solar system, we have examined the best-known bodies: the Earth, Moon, Mars and Mercury. It turns out that despite their differences, they all can be described by multifractral statistics, although with different parameters. Assuming that this property is universal, we propose here a model to simulate 2D spherical random field that mimics a rocky planetary body in a stellar system. We also propose to apply this model to estimate the statistics of oceans and continents to help to better assess the habitability of distant worlds

RF or THz signals generated from DC biased multimode lasers

Although self pulsating (SP) lasers are DC biased, they feature a modulation of the output power. For the results presented in this paper, the SP frequency corresponds to the frequency spacing between longitudinal modes or its second harmonic. The performances of both a 40 GHz self pulsating distributed Bragg reflector laser and of a 660 GHz slotted laser are presented. For the first laser, the radio frequency (RF) signal was analysed on electrical spectrum analyser and its linewidth was smaller that the sum of the main optical modes, proving a passive modelocking of the mode phases. For the slotted laser, a bolometer interfaced to a FT IR spectrometer is used for the terahertz (THz) detection. A signal 10 times larger than the noise level was measured with this set up. Both lasers have demonstrated to be an easy solution to produce RF or THz signal generator

Taxation and International Migration of Superstars: Evidence from the European Football Market

This paper analyzes the effects of top earnings tax rates on the international migration of football players in Europe. We construct a panel dataset of top earnings tax rates, football player careers, and club performances in the first leagues of 14 Western European countries since 1985. We identify the effects of top earnings tax rates on migration using a number of tax and institutional changes: (a) the 1995 Bosman ruling which liberalized the European football market, (b) top tax rate reforms within countries, and (c) special tax schemes offering preferential tax rates to immigrant football players. We start by presenting reduced-form graphical evidence showing large and compelling migration responses to country-specific tax reforms and labor market regulation. We then develop a multinomial regression framework to exploit all sources of tax variation simultaneously. Our results show that (i) the overall location responses to the net-of-tax rate is positive and large, with an elasticity of the number of foreign players to the net-of-tax rate around one (and an elasticity of the number of domestic players around .15), (ii) location elasticities are even larger at the top of the ability distribution, but negative at the bottom due to ability sorting effects, and (iii) cross-tax effects of foreign players on domestic players (and vice versa) are negative and quite strong due to displacement effects. Those results can be rationalized in a simple model of migration and taxation with rigid labor demand.

Optimal Unemployment Insurance Over the Business Cycle

This paper characterizes optimal unemployment insurance (UI) over the business cycle using a model of equilibrium unemployment in which jobs are rationed in recession. It offers a simple optimal UI formula that can be applied to a broad class of equilibrium unemployment models. In addition to the usual statistics (risk aversion and micro-elasticity of unemployment with respect to UI), a macro-elasticity appears in the formula to capture the macroeconomic impact of UI on unemployment. In a model with job rationing, the formula implies that optimal UI is countercyclical. This result arises because in recession, jobs are lacking irrespective of job search. Therefore (1) a higher aggregate search effort cannot reduce aggregate unemployment much; and (2) individual search effort creates a negative externality by reducing other jobseekers' probability of finding a job as in a rat race. Hence the social benefits of job search are low. In a calibrated model, optimal UI increases significantly in recession. This quantitative result holds whether the government adjusts the level or duration of benefits; whether it balances its budget each period or uses deficit spending.Unemployment insurance, business cycle, job rationing, matching frictions

Design of 2D TeraHertz band-gap photonic waveguides using an accelerated integral equation technique

This paper describes the application of the buffered block forward backward (BBFB) method to the problem of modeling 2D terahertz (THz) photonic band gap waveguides at the frequency of 3 THz. The method of moments (MoM) is applied to the integral equation (IE) formulation in order to obtain the linear system that is solved using the BBFB technique. The waveguide dimensions are obtained using the gap map technique

Optimal Unemployment Insurance over the Business Cycle

This paper examines how optimal unemployment insurance (UI) responds to the state of the labor market. The theoretical framework is a matching model of the labor market with general production function, wage-setting mechanism, matching function, and preferences. We show that optimal UI is the sum of a conventional Baily-Chetty term, which captures the trade-off between insurance and job-search incentives, and a correction term, which is positive if UI brings labor market tightness closer to its efficient level. The state of the labor market determines whether tightness is inefficiently low or inefficiently high. The response of optimal UI to the state of the labor market therefore depends on the effect of UI on tightness. For instance, if the labor market is slack and tightness is inefficiently low, optimal UI is more generous than the Baily-Chetty level if UI raises tightness and less generous if UI lowers tightness. Depending on the production function and the wage-setting mechanism, UI could raise tightness, for example by alleviating the rat race for jobs, or lower tightness, for example by increasing wages through bargaining. To determine whether UI raises or lowers tightness in practice, we develop an empirical criterion. The criterion involves a comparison of the microelasticity and the macroelasticity of unemployment with respect to UI.