4 O ct 2 00 5 REGULAR HOMOTOPY AND TOTAL CURVATURE TOBIAS

نویسنده

  • TOBIAS EKHOLM
چکیده

We consider properties of the total absolute geodesic curvature functional on circle immersions into a Riemann surface. In particular, we study its behavior under regular homotopies, its infima in regular homotopy classes, and the homotopy types of spaces of its local minima. We also consider the total curvature functional on the space of 2-sphere immersions into 3-space in a similar spirit. We show that the infimum over all sphere eversions of the maximum of the total curvature during an eversion is at most 8π and we establish a non-injectivity result for local minima.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Regular Homotopy and Total Curvature

We consider properties of the total absolute geodesic curvature functional on circle immersions into a Riemann surface. In particular, we study its behavior under regular homotopies, its infima in regular homotopy classes, and the homotopy types of spaces of its local minima. We also consider the total curvature functional on the space of 2-sphere immersions into 3-space in a similar spirit. We...

متن کامل

Regular homotopy and total curvature I: circle immersions into surfaces

An immersion of manifolds is a map with everywhere injective differential. Two immersions are regularly homotopic if there exists a continuous 1–parameter family of immersions connecting one to the other. The Smale–Hirsch h–principle [8, 4] says that the space of immersions M → N , dim(M) < dim(N) is homotopy equivalent to the space of injective bundle maps TM → TN . In contrast to differential...

متن کامل

m at h . A T ] 2 9 Ju n 20 01 RATIONAL HOMOTOPY THEORY AND NONNEGATIVE CURVATURE

In this note , we answer positively a question by Belegradek and Kapovitch[2] about the relation between rational homotopy theory and a problem in Riemannian geometry which asks that total spaces of which vector bundles over compact nonnegative curved manifolds admit (complete) metrics with nonnegative curvature.

متن کامل

Willmore Two-spheres in the Four-sphere

Genus zero Willmore surfaces immersed in the three-sphere S3 correspond via the stereographic projection to minimal surfaces in Euclidean three-space with finite total curvature and embedded planar ends. The critical values of the Willmore functional are 4πk, where k ∈ N∗, with k 6= 2, 3, 5, 7. When the ambient space is the four-sphere S4, the regular homotopy class of immersions of the two-sph...

متن کامل

un 2 00 4 The homotopy type of the space of symplectic balls in S 2 × S 2 above the critical value

We compute in this note the full homotopy type of the space of symplectic embeddings of the standard ball B(c) ⊂ R (where c = πr is the capacity of the standard ball of radius r) into the 4-dimensional rational symplectic manifold Mμ = (S 2 × S, μω0 ⊕ ω0) where ω0 is the area form on the sphere with total area 1 and μ belongs to the interval (1, 2]. We know, by the work of Lalonde-Pinsonnault, ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2003