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A choice of first-order variables for the characteristic problem of thelinearized Einstein equations is found which casts the system into manifestlywell-posed form. The concept of well-posedness for characteristic problemsinvoked is that there exists an \textit{a priori} estimate of the solution ofthe characteristic problem in terms of the data. The notion of manifestwell-posedness consists of an algebraic criterion sufficient for the existenceof the estimates, and is to characteristic problems as symmetric hyperbolicityis to Cauchy problems. Both notions have been made precise elsewere.Comment: 6 page

Well-posed first-order reduction of the characteristic problem of the linearized Einstein equations