ar X iv : h ep - t h / 96 10 03 1 v 1 7 O ct 1 99 6 INJE – TP – 96 – 5 Higher dimensional extremal black strings

ar X iv : h ep - t h / 99 03 05 4 v 2 2 0 O ct 1 99 9 INJE - TP - 99 - 2 Scattering from an AdS 3 bubble and an exact AdS

ar X iv : h ep - t h / 95 10 12 7 v 4 1 4 D ec 1 99 5 INJE – TP – 95 – 8 Two - dimensional extremal black holes

We discuss the two-dimensional (2D), ǫ < 2 extremal ground states of charged black hole. Here ǫ is the dilaton coupling parameter for the Maxwell term. The complete analysis of stability is carried out for all these extremal black holes. It is found that they are all unstable. To understand this instability, we study the non-extremal charged black hole with two (inner and outer) horizons. The e...

ar X iv : h ep - t h / 95 10 12 3 v 1 1 8 O ct 1 99 5 INJE – TP – 95 – 3 An infinite number of potentials surrounding 2 d black hole

We found an infinite number of potentials surrounding 2d black hole. According to the transmission T and reflection R coefficients for scattering of string fields off 2d black hole, we can classify an infinite number of potentials into three : graviton-dilaton, tachyon and the other types. We suggest that the discrete states from all the Virasoro levels be candidates for new potentials (modes).

ar X iv : h ep - t h / 95 10 12 2 v 1 1 8 O ct 1 99 5 INJE – TP – 95 – 2 Blueshift of tachyon in the charged 2 D black hole

We study the propagation of string fields (metric Gμν , Mawxell gauge potential Aμ, dilaton Φ, and tachyon T ) in a two-dimensional (2D) charged black hole. It is shown that the tachyon is a propagating field both inside and outside the black hole. This becomes infinitely blueshifted at the inner horizon. We confirm that the inner horizon is unstable, whereas the outer horizon is stable. PACS n...

ar X iv : h ep - t h / 96 10 06 1 v 1 9 O ct 1 99 6 Stimulated emission of particles by 1 + 1 dimensional black holes ∗

The stimulated emission of massless bosons by a relativistic and the CGHS black hole are studied for real and complex scalar fields. The radiations induced by one-particle and thermal states are considered and their thermal properties investigated near the horizon. These exhibit both thermal and non-thermal properties for the two black-hole models.