Growth, expectations and tariffs

We study a many-country endogenous growth model in which decisions about innovation and new investment are influenced by growth expectations. Adaptive learning dynamics determine the country-specific short-run transition paths. The countries differ in basic structural parameters and may impose tariffs on imports of capital goods. Numerical experiments illustrate the adjustment dynamics that follow the use of tariffs. We show that countries that limit trade in capital goods can experience dynamic gains both in growth and in utility and that such gains persist longer the larger the structural advantages of the region that applies tariffs. Substantial differences in levels of innovation, consumption, output and utility can appear, and asymmetries in economic outcomes that were present before trade restrictions are made more severe.endogenous growth; expectations; learning; short-run dynamics; tariffs; complementary capital goods

Growth, Expectations, and Tariffs

We study a many country endogenous growth model in which decisions about innovation and new investment are influenced by growth expectations. Adaptive learning dynamics determine country-specific short run transition paths. Countries differ in basic structural parameters and may impose tariffs on imports of capital goods. Numerical experiments illustrate adjustment dynamics that follow the use of tariffs. We show that countries that limit trade in capital goods can experience dynamic gains both in growth and utility and that such gains persist the longer the larger the structural advantages of the region that applies tariffs. Substantial differences in the levels of innovation, consumption, output, and utility can appear, and asymmetries in economic outcomes that were present before trade restrictions are made more severe.endogenous growth, expectations, learning, short run dynamics, tariffs, complementary capital goods

The single-particle density matrix and the momentum distribution of dark "solitons" in a Tonks-Girardeau gas

We study the reduced single-particle density matrix (RSPDM), the momentum distribution, natural orbitals and their occupancies, of dark "soliton" (DS) states in a Tonks-Girardeau gas. DS states are specially tailored excited many-body eigenstates, which have a dark solitonic notch in their single-particle density. The momentum distribution of DS states has a characteristic shape with two sharp spikes. We find that the two spikes arise due to the high degree of correlation observed within the RSPDM between the mirror points ($x$ and $-x$) with respect to the dark notch at $x=0$; the correlations oscillate rather than decay as the points $x$ and $-x$ are being separated.Comment: 9 pages, 8 figure