The purpose of this paper is twofold. First, we use the motivic Landweber
exact functor theorem to deduce that the Bott inverted infinite projective
space is homotopy algebraic K-theory. The argument is considerably shorther
than any other known proofs and serves well as an illustration of the
effectiveness of Landweber exactness. Second, we dispense with the regularity
assumption on the base scheme which is often implicitly required in the notion
of oriented motivic ring spectra. The latter allows us to verify the motivic
Landweber exact functor theorem and the universal property of the algebraic
cobordism spectrum for every noetherian base scheme of finite Krull dimension.Comment: minor revision, essentially in final form, to appear in Proceedings
of the conference on Motives and Algebraic Cycles: A Conference Dedicated to
the Mathematical Heritage of Spencer J. Bloc
