In physics infinity is really less of a problem. Infinity is treated, essentially, as: Really really huge, with no end in sight.<br /><br />Mathematically this almost always is used for approximations. Take two charged particles next to eachother (positive and negative). Close up, you'll see two seperate charges, and a complicated electric field (emerging from the positive, and converging/ending at the negative). Far away however, you'll see a nearly neutral system, and feel almost no electric field. What you do see will have diminished to a very simple system, basically a 1/r^3 (yes r "cubed" ) since the two charges almost, but not quite cancel eachother.<br /><br />To achieve this mathematical answer, we let the "distance" term of the mathematics get really really big (usually making the term it's in get really, really close to zero). I.e. we let distance equal infinity, because it is, for all intents and purposes, if the distance between the particles, compared to the distance we are from them, is very small (i.e. particles are 1 nanometer apart, we're a meter, or 10^9 nanometers away...). <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector. Goes "bing" when there's stuff. It also fries eggs at 30 paces, wether you want it to or not actually. I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>