Laser-produced pair production in vacuum and Hawking-Unruh radiation

Laser generated electron-positron pair production is under discussion in the literature form 1969 and large numbers of positrons have been measured since a few years. For electron-positron pair production in vacuum due to vacuum polarization as predicted by Heisenberg 1934, again much higher laser intensities around 1028W/cm2 are necessary which may be available within a number of years. For these cases the similar electron acceleration by gravitation near black holes at Hawking-Unruh radiation have been discussed since 1985 by McDonald. These conditions are considered in view of the earlier work on pair production, change of statistics for electrons at relativistic black body radiation and an Einstein-recoil mechanism with a consequence of a physical foundation of the fine structure constant.