(of an operator) giving the same result irrespective of the order of the arguments; thus disjunction and addition are commutative but implication and subtraction are not relating to this property: the commutative law of addition 'commutative' also found in these entries (note: many are not synony...
identitiesa + b = b+aandab = ba. In a more general sense, the operationa * bis termed commutative ifa * b = b*a. Addition and multiplication of polynomials, for example, have the property of commutativity; vector multiplication (seeVECTOR PRODUCT) is not commutative since [a,b] = —...
Varying it with respect to xμ, we obtain the surface term(3.1)δSpurebos|=∫∂Σ(∂ixμ+12ϵijkHμνρ∂jxν∂kxρ)δxμnidS, where ni is the unit vector normal to ∂Σ. We will turn on a constant H along the world-volume of the Dirichlet p-brane of the open ...