In a molecular dynamics study we achieved agreement with the phase diagram of nitrogen argon mixtures. Developing model systems in statistical physics, we analyzed phase transitions in crystals, liquid crystals and glasses. Especially we studied transitions from liquids to glasses for repulsive isotropic particles in terms of an infinite cluster series. The sum is a geometric series with a singularity at a critical density. We studied this singularity also with molecular dynamics simulations.
Energy is an important and abstract physical entity.
Nevertheless it can be introduced in a very direct manner using the human sensory system. For instance, a sound is generated by a pendulum hitting a drum. Pupils perceive that the sound remains equally loud, when the mass increases by a factor while the heighth is reduced by the same factor. Fach Physik in einer Klasse 9 eines Gymnasiums. H.-O. Carmesin and S. Arndt.