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::The term "field theory" is still frequently used, so we can't simply "punt" on this. We should explain it as best we can. Under your proposed definition, which is not the meaning of the original term, Newtonian gravity is not a field theory, correct?--[[User:Aschlafly|Andy Schlafly]] 22:17, 15 November 2009 (EST)
::The term "field theory" is still frequently used, so we can't simply "punt" on this. We should explain it as best we can. Under your proposed definition, which is not the meaning of the original term, Newtonian gravity is not a field theory, correct?--[[User:Aschlafly|Andy Schlafly]] 22:17, 15 November 2009 (EST)
::: The functional would be a very special one, which can be aggregated into a function of a few variables since the underlying field does not have any degrees of freedom, but technically you can create a functional which yields the Newtonian gravity. My definition of Field theory would be equivalent to Ksorenson, but i would formulate differently: A field theory formulates equations describing physical reality (equations of motion, for example) in terms of continuous vector-valued degrees of freedom. Solutions of field theories in which fields do not have own degrees of freedom (in the sense that time derivatives of fields do not appear in Hamiltonian Function(al)s/the Equations of motion) are (AFAIU) equivalent to static theories described by effective forces of the point sources of (infinitely fast propagating) fields (e.g. Newtonian Physics, electrostatics). --[[User:Stitch75|Stitch75]] 13:09, 16 November 2009 (EST)
:::Still frequently used by whom? I don't hear teenagers on the subway talking about it. It's a technical term and deserves a technical definition.
:::Still frequently used by whom? I don't hear teenagers on the subway talking about it. It's a technical term and deserves a technical definition.