On Mason’s rigidity theorem
نویسنده
چکیده
Following an argument proposed by Mason, we prove that there are no algebraically special asymptotically simple vacuum space-times with a smooth, shear-free, geodesic congruence of principal null directions extending transversally to a cross-section of I . Our analysis leaves the door open for escaping this conclusion if the congruence is not smooth, or not transverse to I . One of the elements of the proof is a new rigidity theorem for the Trautman-Bondi mass.
منابع مشابه
m at h . A G ] 2 8 Ju n 20 07 Constructing ( almost ) rigid rings and a UFD having infinitely generated Derksen and Makar - Limanov invariant
An example is given of a UFD which has infinitely generated Derksen invariant. The ring is “almost rigid” meaning that the Derksen invariant is equal to the Makar-Limanov invariant. Techniques to show that a ring is (almost) rigid are discussed, among which is a generalization of Mason’s abc-theorem. AMS classification: 14R20, 13A50, 13N15.
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تاریخ انتشار 2008