Regular Homotopy Classes of Immersed Surfaces
نویسنده
چکیده
IN this paper we are concerned with the problem of classifying compact surfaces immersed in Iw” up to regular homotopyt. This subject started in 1958 when Smale classified the immersions of the 2-sphere [17]. For n 2 4 the problem was then completely solved by Hirsch ([8], theorems 8.2 and 8.4): if M2 is a compact surface then for n 2 5 any two immersions f, g : M2 + R” are regularly homotopic, while the immersions f: M2 + R* are completely classified by their normal class. Concerning immersed surfaces in iw3 two results are known:
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تاریخ انتشار 2001