Bitangencies on surfaces in four dimensions

Authors
Dreibelbis, D
Citation
D. Dreibelbis, Bitangencies on surfaces in four dimensions, Q J MATH, 52, 2001, pp. 137-160
Citations number
20
Categorie Soggetti
Mathematics
Journal title
QUARTERLY JOURNAL OF MATHEMATICS
ISSN journal
00335606 → ACNP
Volume
52
Year of publication
2001
Part
2
Pages
137 - 160
Database
ISI
SICI code
0033-5606(200106)52:<137:BOSIFD>2.0.ZU;2-B
Abstract
We derive a formula relating the number of bitangencies, the number of doub le points and the normal Euler number of a generic closed surface in four-d imensional Euclidean space. We give a geometric interpretation of the sign of a bitangency, and also we give a geometric interpretation of the correct ion term (the diagonal contribution) in the formula.