Covariant Description of D-branes in IIA Plane-Wave Background

We work out boundary conditions for the covariant open string in the type IIA plane wave background, which corresponds to the D-branes in the type IIA theory. We use the kappa symmetric string action and see what kind of boundary conditions should be imposed to retain kappa symmetry. We find half BPS as well as quarter BPS branes and the analysis agrees with the previous work in the light cone gauge if the result is available. Finally we find that D0-brane is non-supersymmetric.Comment: 13 pages, v3: one more reference added, version to appear in Physics Letter

The Very Dark Side of Internal Capital Markets: Evidence from Diversified Business Groups in Korea

This paper examines the capital allocation within Korean chaebol firms during the period from 1991 to 2000. We find strong evidence that, during the pre-Asian financial crisis period in the early 1990's, poorly performing firms with less investment opportunities invest more than well-performing firms with better growth opportunities. We also find the evidence of cross-subsidization among firms in the same chaebol group during the pre-crisis period. It appears that the existence of the "dark" side of internal capital markets explains most part of this striking phenomenon where "tunneling" practice has been common during the pre-crisis period. However, the inefficient capital allocation seems to disappear after the crisis as banks gain more power and market disciplines inefficient chaebol firms.

Information Technology Investment and National Productivity

Using the country-level information technology (IT) expenditures and productivity data for the period from 1992 to 2000, we estimate production function augmented with IT capital stock in the first-difference form. As discussed in prior studies, we confirm that IT expenditures have significant positive effects on national productivity growth. The effects of IT expenditure on productivity growth hold for a short-term (1-year) as well as for a longer-term (4-year and 8-year). Using two theory-based measures of IT maturity, we find that the IT maturity is an important factor that explains the relationship between IT expenditures and national productivity. In addition, we find that the effect of IT expenditures is even higher when the countries are at the mature stage of IT expenditures. Furthermore, we present evidence that IT externalities improve the effect of IT expenditures on productivity growth

Do Main Banks Extract Rents from their Client Firms? Evidence from Korean Chaebol

Using a unique data set on all industrial firms listed on Korea Stock Exchange and KOSDAQ stock market from 1991 to 2000, we find that cash ratios for chaebol firms are lower than for non-chaebol firms. Controlling for access to the bond market and financial services arms does not change this result. We do however find that there is a shift in the degree of bank power over the last decade. Consistent with the main bank monopoly hypothesis during the corporate restructuring process after the financial crisis in 1997, the interest differential charged to chaebol firms is significantly higher than the earlier period, suggesting extraction of rents against chaebol client firms by main banks.Cash holdings, bank power, rent extraction, Korean chaebol

Chapter 1 Introduction

There is an increasing tendency to use the development experience of Asian countries as a reference point for other countries in the Global South. Korea’s condensed urbanization and industrialization, accompanied by the expansion of new cities and industrial complexes across the country, have become one such model, even if the fruits of such development may not have been equitably shared across geographies and generations. The chapters in this book critically reassess the Korean urban development experience from regional policy to new town development, demonstrating how these policy experiences were deeply rooted in Korea’s socioeconomic environment and discussing what can be learned from them when applying them in other developmental context

Thermodynamics of Fuzzy Spheres in PP-wave Matrix Model

We discuss thermodynamics of fuzzy spheres in a matrix model on a pp-wave background. The exact free energy in the fuzzy sphere vacuum is computed in the \mu -> \infty limit for an arbitrary matrix size N. The trivial vacuum dominates the fuzzy sphere vacuum at low temperature while the fuzzy sphere vacuum is more stable than the trivial vacuum at sufficiently high temperature. Our result supports that the fluctuations around the trivial vacuum would condense to form an irreducible fuzzy sphere above a certain temperature.Comment: 18 pages, 4 figures, LaTeX2

Membrane Fuzzy Sphere Dynamics in Plane-Wave Matrix Model

In plane-wave matrix model, the membrane fuzzy sphere extended in the SO(3) symmetric space is allowed to have periodic motion on a sub-plane in the SO(6) symmetric space. We consider a background configuration composed of two such fuzzy spheres moving on the same sub-plane and the one-loop quantum corrections to it. The one-loop effective action describing the fuzzy sphere interaction is computed up to the sub-leading order in the limit that the mean distance $r$ between two fuzzy spheres is very large. We show that the leading order interaction is of the 1/r^7 type and thus the membrane fuzzy spheres interpreted as giant gravitons really behave as gravitons.Comment: 28 pages, LaTeX2e, 1 figure, 1 tabl

A note on D-brane Interactions in the IIA Plane-Wave Background

We compute the D-brane tensions in the type IIA plane-wave background by comparing the interaction potential between widely separated D-branes in string theory with the supergravity mode exchange between the D-branes. We found that the D-brane tensions and RR charges in the plane-wave background are the same as those in the flat space. Also we work out the stringy halo behavior of the $DpD\bar{p}$ spacelike branes and find the explicit dependence on the light cone separation $r^+$. This suggests that the detailed tachyon dynamics for the spacelike $DpD\bar{p}$ branes are different from those in the flat space case. We also discuss specific features of the exchange amplitudes in relation to the geometric properties of the IIA plane wave background. When branes are located at focal points, full or partial restoration of the translation invariance occurs and the amplitudes are similar to those in the flat space.Comment: 19 pages; discussions on the integrated amplitudes in geometric terms adde