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Using spinning we analyze in a geometric way Haefliger's smoothly
knotted (4k-1)–spheres in the 6k–sphere. Consider the
2–torus standardly embedded in the 3–sphere, which is
further standardly embedded in the 6–sphere. At each point of
the 2–torus we have the normal disk pair: a 4–dimensional
disk and a 1–dimensional proper sub-disk. We consider an isotopy
(deformation) of the normal 1–disk inside the normal 4–disk,
by using a map from the 2–torus to the space of long knots in
4–space, first considered by Budney. We use this isotopy in a
construction called spinning about a submanifold introduced
by the first-named author. Our main observation is that the resultant
spun knot provides a generator of the Haefliger knot group of knotted
3–spheres in the 6–sphere. Our argument uses an explicit
construction of a Seifert surface for the spun knot and works also for
higher-dimensional Haefliger knots.
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