zbMATH — the first resource for mathematics

Geometry Search for the term Geometry in any field. Queries are case-independent.
Funct* Wildcard queries are specified by * (e.g. functions, functorial, etc.). Otherwise the search is exact.
"Topological group" Phrases (multi-words) should be set in "straight quotation marks".
au: Bourbaki & ti: Algebra Search for author and title. The and-operator & is default and can be omitted.
Chebyshev | Tschebyscheff The or-operator | allows to search for Chebyshev or Tschebyscheff.
"Quasi* map*" py: 1989 The resulting documents have publication year 1989.
so: Eur* J* Mat* Soc* cc: 14 Search for publications in a particular source with a Mathematics Subject Classification code (cc) in 14.
"Partial diff* eq*" ! elliptic The not-operator ! eliminates all results containing the word elliptic.
dt: b & au: Hilbert The document type is set to books; alternatively: j for journal articles, a for book articles.
py: 2000-2015 cc: (94A | 11T) Number ranges are accepted. Terms can be grouped within (parentheses).
la: chinese Find documents in a given language. ISO 639-1 language codes can also be used.

a & b logic and
a | b logic or
!ab logic not
abc* right wildcard
"ab c" phrase
(ab c) parentheses
any anywhere an internal document identifier
au author, editor ai internal author identifier
ti title la language
so source ab review, abstract
py publication year rv reviewer
cc MSC code ut uncontrolled term
dt document type (j: journal article; b: book; a: book article)
The heat equation shrinks embedded plane curves to round points. (English) Zbl 0667.53001
This paper contains the final solution of the long-standing “curve- shortening problem” for plane curves: Let $\gamma\sb 0: S\sp 1\to {\bbfR}\sp 2$ be a regular embedded closed plane curve. Then the evolution equation ${\dot \gamma}=k\cdot N$ (N a unit normal field, k the curvature) with initial condition $\gamma (0,s)=\gamma\sb 0(s)$ always has a solution $\gamma: {\bbfR}\sp+\times S\sp 1\to {\bbfR}\sp 2,$ $S\mapsto \gamma\sb t(s)=\gamma (t,s)$ is an embedded curve for all t and $\gamma\sb t$ approaches a (shrinking) round circle as $t\to \infty$.
Reviewer: U.Pinkall

53A04Curves in Euclidean space
35G10Initial value problems for linear higher-order PDE
35K25Higher order parabolic equations, general