Mike wrote, "I urge you to learn up on some basics physics before claiming it is inconsistent with the acentric model." What you really mean is that you urge me to propound the conventional explanation for a "phenomenon" that I do not accept. I have provided this group, I think, with the physical basis for my non-acceptance (not just the Biblical basis). Your problem, if you don't mind me saying so, is that your physics is somewhat too basic. A good example of what I mean is your following comment that, "Elastic or not, every action has an equal and opposite reaction. Are you now saying that linear momentum isn't conserved when two particles collide?" It is not conserved in an inelastic collision, no. I suggest that you wander over to the Physics Department at Imperial and ask someone who knows what they are talking about to explain this to you. Furthermore, any collision between billiard balls is inelastic. Regards, Neville. --------------------------------- ALL-NEW Yahoo! Messenger - all new features - even more fun!