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THIS PAPER ADVOCATES A MARKOV CHAIN MODEL OF WAR AS SUPERIOR TO THE SIMPLER OCCURRENCE OF WAR MODEL AS A METHOD OF RESEARCH INTO THE CAUSES OF WAR, WHEN WAR AND PEACE ARE CONCEIVED OF AS DESCRETE STATES SEPARATED BY RELATIVELY RAPID PROCESSES OF ESCALATION AND DEESCALATION. EMPIRICAL RESULTS SUPPORT THE NOTION THAT THE MILITARY RIVALRY BETWEEN THE SUPERPOWERS AND THEIR ALLIES HAS BEEN PLAYED OUT IN THE THIRD WORLD, AND THAT THE CONSEQUENCE IS A DRAMATIC INCREASE IN MILITARISM AND WAR IN THAT PART OF THE WORLD.

We report on experiments irradiating isolated plastic spheres with a peak laser intensity of 2-3 x 10(20) W cm(-2). With a laser focal spot size of 10 mu m full width half maximum (FWHM) the sphere diameter was varied between 520 nm and 19.3 mu m. Maximum proton energies of similar to 25 MeV are achieved for targets matching the focal spot size of 10 mu m in diameter or being slightly smaller. For smaller spheres the kinetic energy distributions of protons become nonmonotonic, indicating a change in the accelerating mechanism from ambipolar expansion towards a regime dominated by effects caused by Coulomb repulsion of ions. The energy conversion efficiency from laser energy to proton kinetic energy is optimized when the target diameter matches the laser focal spot size with efficiencies reaching the percent level. The change of proton acceleration efficiency with target size can be attributed to the reduced cross-sectional overlap of subfocus targets with the laser. Reported experimental observations are in line with 3D3V particle in cell simulations. They make use of well-defined targets and point out pathways for future applications and experiments. ; DFG via the Cluster of Excellence Munich-Centre for Advanced Photonics (MAP) Transregio SFB TR18 ; NNSA DE-NA0002008 ; Super-MUC pr48me ; Ivo Cermak ; CGC Instruments in design and realization of the Paul trap system ; IMPRS-APS ; LMUexcellent Junior Research Fund ; DAAD|ToIFE ; European Union's Horizon research and innovation programme 633053 ; Physics