What is Samadhi? Stopping the mind. The mind itself has no qualities, it only carries the momentum of what it comes into contact with, and when the mind stops, reality emerges. This is why all yoga is designed to bring about the event of Samadhi.
Everybody talks about ascending to the higher planes. This process involves making the mind perfectly empty, and the first stage of this process is stopping the mind, and stopping it for increasingly sustained periods of time. When this occurs, the event of enlightenment arises.