Hrm. I really don't like the current definition of physics. Matter and the four fundamental forces? That just doesn't sound right. Where does energy fit in? Matter's just a subset of energy. There's got a be a better way, something about "basic interactions". (One def I saw was "matter and energy and their interactions")
I also wouldn't restrict physics to the "four fundamental forces". After all, there's the basic assertion that there's really only one "fundamental" force.
So if you don't want to use the basic "science of nature", its historical definition, perhaps some def w/the buzzwords "matter", "energy","laws","forces".
I would merge, rather than replace. For instance, the subfields in /Schemes is sparse compared to the American Physical Societies section of main. The central theories area of /Schemes also intersperses theories with full blown areas of study (i.e. thermodynamics isn't one theory, whilst special relativity is).
As for a definition, may I suggest:
Physics is the study of nature in the broadest sense. Physicists attempt to find the most general rules that govern all of nature. Physics generally breaks down in to the study of the properties of matter, fields, space, time, and energy and how they interact. To describe these phenomena, physicists generally us the most precise language available to them, mathematics.
Or something of that general sort. Perhaps even a mention that physics really is the study of everything in nature (i.e., mention that chemistry is a subset of physics that is governed by the molecular-atomic description of matter, and that biology is a subset of chemistry). Just musing. --BlackGriffen
Ok, I like your definition and agree that I should incorporate more subfields. Do you think thermodynamcis fits better as a subfield? I think it is pretty close to a theory: a bunch of definitions, a small number of laws, and then only consequences.
I'm not sure all biologist would agree with your reductionist view of biology as a subset of chemistry as a subset of physics, so I don't want to go there. Biologists pose and answer questions that are different from questions of physics. For instance, even if you knew all laws of physics, you still wouldn't know why we have our eyes in the head and not on our asses. --AxelBoldt
On the /Schemes page, I've changed Laser science to Optics, since it's a little more top-level, and doesn't really fit anywhere else. Lasers are a completely enclosed subfield of Optics, in my opinion -- DrBob
It looks like a lot of what has been added to this page belongs to History of Physics which is empty.