2009/01/16 by Vladimir Oliker, Oliker, Vladimir
Mathematics · #35J60 #58J05 #Analysis of PDEs (math.AP) #Differential Geometry (math.DG) #FOS: Mathematics #math.AP #math.DG #msc:35J60 #msc:58J05
paper · pdf · doi:10.48550/arxiv.0901.2511
22 pages. This is a substantially revised and expanded version of an earlier posted paper
arxiv created 2009/09/16 · arxiv updated 2009/12/01
For a congruence of straight lines defined by a hypersurface in Rn+1, n ≥ 1, and a field of reflected directions created by a point source we define the notion of intensity in a tangent direction and introduce elementary symmetric functions Sm, m=1, 2,...,n, of \it principal intensities. The problem of existence and uniqueness of a closed hypersurface with prescribed Sn is the "reflector problem" extensively studied in recent years. In this paper we formulate and give sufficient conditions for solvability of an analogous problem in which the mean intensity S1 is a given function.