The simple pendulum is a very known physical problem, however, it's interesting to note that this simple system don't have a exact solution. Let be (1) the potential of the pendulum with mass m. Now the Lagrangian is (2) Equation of motion can be...

This video reviews the efforts of numerical relativity and visualization aspects of general relativity. It among the top 10 of the 1st NSF Science & Engineering Visualization Challenge Contest in 2003.

No doubt that significance of Eugene Parker's model of solar wind was the fact that it assumed a non static solar corona, predicting the existence of solar wind, completely unknown at that time. Here I will explain this interesting model, and his...

This is a simple classical calculation, that is useful to understand how dark matter is distributed around spiral galaxies. First, consider a star moving due to gravity of a galactic nucleus. In dynamic equilibrium, gravitational force is equal to...