| MadSci Network: Physics |
This is more a question about how humans think than about physics. We like to analyze things: we try to identify how things are the same and how they are different, we try to figure out how things work. We might ask, how many parts are there to a person? You could argue that there's just one part to yourself: your whole body. It's not helpful, though, when you get sick. When a doctor asks, "Where does it hurt?" you want to be able to identify a more specific part of yourself like your throat or your hand. Your doctor, though, might look at your hand and not see one part but hundreds of parts. If you slammed the car door on your hand, your doctor might care about which of dozens of bones may have been hurt. If you burnt your hand, your doctor may care about which layers of skin were damaged. If you sprain your wrist, your doctor may be more interested in particular muscles. So, when you consider something like an atom, how many parts you find important reflect what you are interested in. A chemist may be most interested in the number of electrons and protons, because those are the parts that affect how atoms bind together to make the materials we live with. I'm a nuclear physicist, so i really don't care about the electrons; i'm interested in the protons and neutrons and the parts that hold them together. Other physicists are interested in the quarks which are the parts of protons and neutrons. It seems that quarks are the smallest parts of matter we will ever identify, but science -- and scientists -- always look for surprises. The very best answer i can give to your question is that we humans are very very curious. The more curious we are, the more we identify distinctions and 'parts,' as we try to understand how the world works around us. Judith E. Bush jbush@fi.edu The Franklin Institute Science Museum New Media Specialist 222 N. 20th Street 1 (215) 448-1236 Philadelphia, PA 19103-1194 USA AOL IM judielaine
Try the links in the MadSci Library for more information on Physics.