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SUMMARY:Knotted surfaces in 4-manifolds and distances between them - Olive
 r Singh\, Durham
DTSTART:20191106T160000Z
DTEND:20191106T170000Z
UID:TALK126928@talks.cam.ac.uk
CONTACT:Ivan Smith
DESCRIPTION:I will discuss knotted surfaces\, isotopy classes of embedded 
 surfaces in a given 4-manifold\, and will define two notions of distance b
 etween them. These distances are integer-valued and are defined topologica
 lly: one in terms of regular homotopy\; another in terms of stabilisation\
 , a form of embedded surgery. I will outline a proof of an inequality betw
 een these distances\; the proof is constructive and draws upon ideas pione
 ered by Gabai in the proof of the 4-dimensional light bulb theorem.
LOCATION:MR13
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