SLAC-PUB 7326 SNUTP-96/105 SU-ITP 96-44 hep-th/9610157 CLASSICAL AND QUANTUM ASPECTS OF BPS BLACK HOLES IN N = 2;D = 4 HETEROTIC STRING COMPACTIFICATIONS

We study classical and quantum aspects of D = 4; N = 2 BPS black holes for T2 compacti cation of D = 6; N = 1 heterotic string vacua. We extend dynamical relaxation phenomena of moduli elds to background consisting of a BPS soliton or a black hole and provide a simpler but more general derivation of the Ferrara-Kallosh's extremized black hole mass and entropy. We study quantum e ects to the the BPS black hole mass spectra and to their dynamical relaxation. We show that, despite non-renormalizability of string e ective supergravity, quantum e ect modi es BPS mass spectra only through coupling constant and moduli eld renormalizations. Based on target-space duality, we establish a perturbative non-renormalization theorem and obtain exact BPS black hole mass and entropy in terms of renormalized string loop-counting parameter and renormalized moduli elds. We show that similar conclusion holds, in the large T2 limit, for leading non-perturbative correction. We nally discuss implications to type-I and type-IIA Calabi-Yau black holes. Submitted to Nuclear Physics B 1Work supported in part by DOE DE-AC03-76SF00515, NSF Grant PHY-9219345, NSF-KOSEF Bilateral Grant, KRF International Collaboration Grant and Non-Directed Research Grant 81500-1341, KOSEF Purpose-Oriented Research Grant 94-1400-04-01-3 and SRC Program, the Ministry of Education BSRI Grant 96-2418, and the Seoam Foundation Fellowship. 2email: [email protected], [email protected], [email protected]