Does the math for collision detection occur in java or openGL?

I want to create my own physics engine for JME but I'm not sure if the calculations are done directly in Java or if OpenGL has the graphics card do them or what.  Does anyone know how JME does the math for collisions.  I'm familiar with the math used by the physics engine just not how I can efficiently call that.  Thanks for any help you can provide.

I can't offer much assistance other than suggesting you look at some of the physics implementations that are already floating around the forums for some insight. Search for Simple Physics, it might give you a good idea about your question.