- What is spacetime? Minkowski's spacetime concept explained.
- Is space travel possible? Have we ever been visited by aliens? A scientific approach (rocket dynamics) to this question.
- Well know problems from cosmology, Olber's paradox and its counterpart the Gravity paradox, both solved! (and maybe there is some link with Mach's principle?)
- Another well know problem, The Arrow of Time, solved!
- The Human Engine (Menselijke Motor). The human body as an engine. (In Dutch)
- The Origin and Solutions of the Wave Equation.
- Conditional probability explained. (In Dutch)
- Astronomical Distance Scales.