Research work · 1996

Entropy of 4D Extremal Black Holes

Clifford V. Johnson, Ramzi R. Khuri, Robert Cobb Myers

Abstract

We derive the Bekenstein–Hawking entropy formula for four–dimensional Reissner– Nordström extremal black holes in type II string theory. The derivation is performed in two separate (T–dual) weak coupling pictures. One uses a type IIB bound state problem of D5 – and D1–branes, while the other uses a bound state problem of D0 – and D4–branes with macroscopic fundamental type IIA strings. In both cases, the D–brane systems are also bound to a Kaluza–Klein monopole, which then yields the four–dimensional black hole at strong coupling.