Is it true that mass and energy are interchangable? If mass were to be defined as "the force of matter", is it then true that matter and energy are two states of the same thing? Is matter condensed or frozen energy? Could radioactive decay be defined as the sublimation of matter into energy? Is it fair to conclude that no two discernable entities of matter could ever possibly come into direct contact with each other, but instead can only forever appraoch each other? If I place two glass marbles up against each other and examine the point of apparant contact very closely what exactly could I expect to discover? As I magnify this point more and more will I not find that the surface of the glass marbles is far from even and smooth? Will I not also initially see that there are probably several dozens and perhaps thousands of points that appear to be touching on the two surfaces that are now irregular and rough shod? Able to choose only one point to zoom in on at a time will I not eventually discover that each point of apparant contact reacts the same to my inspection, in that it proliferates into many more points the more I magnify it? Eventually when I zoom in to the "molecular" level doesnt my question change from that of one inquiring if two marbles can touch to one asking if two molecules can touch? As I zoom in even more, thus altering my perspective yet again, doesnt my question also change? Soon I am now observing the weak and strong nuclear forces, am I not? I press the two marbles together as hard as I can, but as I continue to zoom in it appears that the marbles (which by now appear to be two dense galaxies of particulate debris organized by so many forces I dont understand) are pushing against each other before they touch--is this true, or even fair to say? I apologize for the breathlessly long inquiry. I have a high schoolers grasp of physics, perhaps even less, and I'd definately appreciate any response offered to the above.