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Do asymptotically conformal maps converge to a weakly conformal map?

$\newcommand{\CO}{\text{CO}_2}$ $\newcommand{\SO}{\text{SO}_2}$ $\newcommand{\dist}{\text{dist}}$ $\newcommand{\M}{\mathcal{M}}$ $\newcommand{\N}{\mathcal{N}}$ Let $\M,\N$ be two-dimensional smooth, ...
Asaf Shachar's user avatar
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6 votes
0 answers
171 views

The distributional gradient of the closest isometry to the differential of a smooth map

The setting-a "linear algebra" fact: Let $A$ be a real $n \times n$ matrix, and suppose that $\det A<0$ and that the singular values of $A$ are distinct. Then, there exist a unique matrix $Q(A) \...
Asaf Shachar's user avatar
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5 votes
0 answers
114 views

Varifold convergence of images of Sobolev maps

Suppose I have a sequence of maps $\{f_k:\Omega\subset\mathbb{R}^n\rightarrow\mathbb{R}^{n+1}\}$ such that: $f_k\rightharpoonup f_*$ weakly in $W^{1,p}(\Omega,\mathbb{R}^{n+1})$, The images $\Sigma_k:...
sobol's user avatar
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5 votes
1 answer
504 views

Tangent cones at zero and infinity to minimal surfaces

Let $n \geq 2$, and let $M^n \subset \mathbf{R}^{n+1}$ be a minimal surface with $0 \in M$ and finite ($n$-dimensional) area growth: $\operatorname{limsup}_{R \to \infty} R^{-n} \lVert M \cap B_R \...
Leo Moos's user avatar
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4 votes
0 answers
162 views

Density of smooth functions in the calculus of variations

In the non-convex calculus of variations, in the context of non-linear elasticity, the following classes of mappings $u:\Omega\to\mathbb{R}^n$, $\Omega\subset\mathbb{R}^n$, were introduced by John ...
Piotr Hajlasz's user avatar
3 votes
0 answers
102 views

When is the least-area surface unique?

Let $M^{n-1}$ be a smooth closed manifold, embedded into the round sphere $\mathbf{S}^n$ via a regular map $\Phi$. Using tools from geometric measure theory, one can prove the existence of a $n$-...
Leo Moos's user avatar
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3 votes
0 answers
278 views

What are the most general types of curves in $\mathbb{R}^2$ for which Gauss-Bonnet holds?

I would like to know what is the most general form of the Gauss-Bonnet theorem in the plane for curves. It is well known for that for any piecewise $C^2$ simply connected curve with corners, one has $...
Dorian's user avatar
  • 2,641
3 votes
0 answers
401 views

Generalization of First Variation of Area

The area of an $m$-rectifiable varifold in $n$-dimensional space can be expressed in terms of the surface divergence. More precisely, if $M$ is $m$-rectifiable, $\Omega$ is open, $\eta$ is a $C^1_c$ ...
Martijn's user avatar
  • 320
2 votes
0 answers
65 views

Defining minimality 'through deformations'

Let $U \subset \mathbf{R}^{n+k}$ be a bounded open set, and $T \in \mathbf{I}_n(U)$ be an $n$-dimensional integral rectifiable current. Say that $T$ is stationary through (homological) deformations if ...
Leo Moos's user avatar
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2 votes
0 answers
77 views

Area of minimising surface

I am interested in calculating the least area of a surface spanning the boundary of an octant on the unit sphere; and short of precise values I am looking for upper bounds for this area. In $\mathbf{S}...
Leo Moos's user avatar
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2 votes
0 answers
82 views

Volume of critical points decreases under symmetric decreasing rearrangement

In the lecture note http://www.math.utoronto.ca/almut/rearrange.pdf, it was stated that the volume of the set of critical points decreases under symmetric decreasing rearrangement. It seems so obvious ...
big_huong's user avatar
2 votes
0 answers
115 views

Currents with mean curvature

so let $T=\tau(M,\theta,\xi)$ a rectifiable current in $U\subset\mathbb{R}^{n+k}$, then $T$ has mean curvature vector $H$ if for every $X\in C^1_c(U\setminus\partial T,\mathbb{R}^{n+k})$ the variation ...
leander's user avatar
  • 43
2 votes
0 answers
285 views

Method of proving the regularity of the minimizer of geometric variational problems

Recall the proof of the $(\Lambda,r_0)$-perimeter minimizer. We say that $E$ is a $(\Lambda,r_0)$-perimeter minimizer in an open set A provided $sptD\chi_E=\partial E$ and there exist two constants $...
student's user avatar
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2 votes
0 answers
175 views

An isoperimetric type maximization problem with a barrier.

I'm trying to minmize a particular functional which depends on a curve with fixed endpoints which lies below a fixed line in $\mathbb{R}^2$. Here are the details: Let $(r(\theta), \theta)$ be a ...
Dorian's user avatar
  • 2,641
1 vote
0 answers
96 views

Periodic orbits in planar smooth billiard table with large periods

Given a plane billiard table with a smooth boundary which is a Jordan curve, I wonder if there is always a periodic orbit with sufficiently large period. Formulation of my question: We are considering ...
XYC's user avatar
  • 441
1 vote
0 answers
97 views

Reference request: theory for local minimizers in the calculus of variations

Let $F: \mathbb{R}^n \times \mathbb{R} \times \mathbb{R}^n \to \mathbb{R}$ be the Lagrangian. We say that $f \in X$ is a local minimizer of the variational integral if for all compact sets $C \subset \...
Franlezana's user avatar
1 vote
0 answers
157 views

Does a sequence of Jacobians converge to the 'correct' continuous part plus some controlled singular part?

$\newcommand{\M}{\mathcal{M}}$ $\newcommand{\N}{\mathcal{N}}$ Let $\M,\N$ be two-dimensional smooth, compact, connected, oriented Riemannian manifolds. (with or without boundaries). Let $f_n \in W^{1,...
Asaf Shachar's user avatar
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1 vote
0 answers
64 views

decomposition of codim 1 currents

Let $T$ be an codimension one rectifiable mass-minimizing current. If $\partial T\llcorner B_R(a)=0$, then it is possible to write $T$ as an infinite sum of oriented boundaries: $T\llcorner B_R(a)=\...
leander's user avatar
  • 43
0 votes
0 answers
38 views

A general rule for approximating the perimeter of a set with finite perimeter in terms of the volume

I want to know if it is possible to have a general rule for approximating the perimeter of a set $E\subset \mathbb{R}^n$ with finite perimeter in terms of the volume (Lebesgue measure) of a sequence ...
XIII's user avatar
  • 747
0 votes
0 answers
43 views

Minimal condition on set for an optimisation problem

We fix $\Omega \subset \mathbb{R}^{2}$ an open set. My question is: what are the minimum conditions we need on $E \subset \Omega$ such that the following optimisation problem: $$ \sup\{ \int_{E}(\...
JaberEdgar's user avatar