EXPT is exponentiation. It is defined for numbers in the kif-numbers ontology. Here it is extended to physical quantities and physical dimensions.
and also:
{The term {tt (expt $tau_1$ $tau_2$)} denotes the object denoted by
$tau_1$ raised to the power the object denoted by $tau_2$.}
(=> (And (Physical-Dimension ?D) (Real-Number ?Exp) (Expt ?D ?Exp ?Dim)) (Physical-Dimension ?Dim)) (=> (And (Physical-Quantity ?X) (Real-Number ?R) (Expt ?X ?R ?Z)) (And (Physical-Quantity ?Z) (= (Quantity.Dimension ?Z) (Expt (Quantity.Dimension ?X) ?R))))
(Forall (?D1 ?D2 ?R1 ?R2) (=> (And (Physical-Dimension ?D1) (Physical-Dimension ?D2) (Real-Number ?R1) (Real-Number ?R2)) (And (= (Expt ?D1 0) Identity-Dimension) (= ?D1 (Expt ?D1 1)) (= (* (Expt ?D1 ?R1) (Expt ?D1 ?R2)) (Expt ?D1 (+ ?R1 ?R2))) (= (Expt (* ?D1 ?D2) ?R1) (* (Expt ?D1 ?R1) (Expt ?D2 ?R1))) (= (Expt (Expt ?D1 ?R1) ?R2) (Expt ?D1 (* ?R1 ?R2)))))) (Forall (?X1 ?X2 ?R1 ?R2) (=> (And (Physical-Quantity ?X1) (Physical-Quantity ?X2) (Real-Number ?R1) (Real-Number ?R2)) (And (= (* (Expt ?X1 ?R1) (Expt ?X1 ?R2)) (Expt ?X1 (+ ?R1 ?R2))) (= (Expt (* ?X1 ?X2) ?R1) (* (Expt ?X1 ?R1) (Expt ?X2 ?R1))) (= (Expt (Expt ?X1 ?R1) ?R2) (Expt ?X1 (* ?R1 ?R2))))))
(= (Recip ?X) (Expt ?X -1)) (=> (And (Physical-Quantity ?X) (Recip ?X ?Y)) (And (Physical-Quantity ?Y) (= (Quantity.Dimension ?Y) (Expt (Quantity.Dimension ?X) -1)))) (Forall (?D1 ?D2 ?R1 ?R2) (=> (And (Physical-Dimension ?D1) (Physical-Dimension ?D2) (Real-Number ?R1) (Real-Number ?R2)) (And (= (Expt ?D1 0) Identity-Dimension) (= ?D1 (Expt ?D1 1)) (= (* (Expt ?D1 ?R1) (Expt ?D1 ?R2)) (Expt ?D1 (+ ?R1 ?R2))) (= (Expt (* ?D1 ?D2) ?R1) (* (Expt ?D1 ?R1) (Expt ?D2 ?R1))) (= (Expt (Expt ?D1 ?R1) ?R2) (Expt ?D1 (* ?R1 ?R2)))))) (=> (And (Physical-Dimension ?D) (Real-Number ?Exp) (Expt ?D ?Exp ?Dim)) (Physical-Dimension ?Dim)) (Forall (?X1 ?X2 ?R1 ?R2) (=> (And (Physical-Quantity ?X1) (Physical-Quantity ?X2) (Real-Number ?R1) (Real-Number ?R2)) (And (= (* (Expt ?X1 ?R1) (Expt ?X1 ?R2)) (Expt ?X1 (+ ?R1 ?R2))) (= (Expt (* ?X1 ?X2) ?R1) (* (Expt ?X1 ?R1) (Expt ?X2 ?R1))) (= (Expt (Expt ?X1 ?R1) ?R2) (Expt ?X1 (* ?R1 ?R2)))))) (=> (And (Physical-Quantity ?X) (Real-Number ?R) (Expt ?X ?R ?Z)) (And (Physical-Quantity ?Z) (= (Quantity.Dimension ?Z) (Expt (Quantity.Dimension ?X) ?R)))) (=> (And (Physical-Quantity ?X) (Physical-Quantity ?Y)) (= (/ ?X ?Y) (* ?X (Expt ?Y -1)))) (=> (And (Unit-Of-Measure ?A) (Real-Number ?B)) (Unit-Of-Measure (Expt ?A ?B))) (<=> (Dimension-Composable-From ?Dim ?Set-Of-Dimensions) (Or (Member ?Dim ?Set-Of-Dimensions) (Exists (?Dim1 ?Dim2) (And (Dimension-Composable-From ?Dim1 ?Set-Of-Dimensions) (Dimension-Composable-From ?Dim2 ?Set-Of-Dimensions) (= ?Dim (* ?Dim1 ?Dim2)))) (Exists (?Dim1 ?Real) (And (Dimension-Composable-From ?Dim1 ?Set-Of-Dimensions) (Real-Number ?Real) (= ?Dim (Expt ?Dim1 ?Real))))))