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1 vote
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76 views

Translate of a geodesic that goes through a fixed point on $\mathbb{H}$

Consider the complex upper half plane $\mathbb{H}$ with the hyperbolic geometry. Fix a point $z \in \mathbb{H}$ and also a geodesic $c$. I want to find a hyperbolic translation $\gamma c$ passes that ...
Melanka's user avatar
  • 577
0 votes
1 answer
175 views

Reference request: How to construct a diffeomorphism between point clouds

I'm interested in the following question: Given two sets $S = \{x_1, ..., x_N\}$ and $T = \{y_1, ..., y_N\}$ each consisting of $N$ distinct points in $\mathbb{R}^n$, how can we construct a ...
ccriscitiello's user avatar
3 votes
2 answers
157 views

Finding a point inside a surface

I have a triangulation of a surface without boundary in $\mathbb{R}^3$. The triangulation gives a unit normal pointing outwards for each triangle. I need to find some point in the interior of the ...
quirkyquark's user avatar
1 vote
0 answers
87 views

On vertices on convex smooth closed surfaces

Question: Given a smooth, convex, closed surface. How would one find points on it with the property: the average of the geodesic distances from that point to all other points on the surface (the ...
Nandakumar R's user avatar
  • 5,979
2 votes
1 answer
223 views

Discrete curve-shortening flow – numerical implementation

I need to investigate the properties of open curves which evolve according to the standard curve-shortening flow (Wikipedia link), but with fixed extremes as boundaries (si it should converge to the ...
rndm_ecn's user avatar
8 votes
1 answer
316 views

What is the form of the $(v_0,v_1)$-pizza curve?

Assume that there are two (competing) pizza houses situated at the points $0$ and $1$ on the complex plane. These pizza houses can deliver pizza to points of the plane with the largest velocities $v_0$...
Taras Banakh's user avatar
  • 41.9k
2 votes
2 answers
399 views

Computer algebra for calculating curvature when the tensor metric is very big

Is there a computer algebra method to compute the curvature of a Riemannian metric on the plane when the metric tensor has long entries $E,F,G$ The computation by hand is very ...
Ali Taghavi's user avatar
5 votes
0 answers
1k views

Reach of manifold vs. $C^k$-manifold

The reach $\tau_M$ of a manifold $M$ is the largest number such that any point at distance less than $\tau_M$ from $M$ has a unique nearest point on $M$. This concept seems quite related to the local ...
Joseph O'Rourke's user avatar
0 votes
1 answer
124 views

Triangle inside the Closed Curve

For any piece wise smooth, simple closed curve $\gamma$ in the Euclidean plane $E^2$ and fix a point $G$ inside the area circled by $\gamma$. Show: There exists three points $A,B$ and $C$ on the $\...
DLIN's user avatar
  • 1,915
6 votes
1 answer
148 views

Does a minimum area disk that is bounded by a cycle $C$ continuously deform in $R^3$ as $C$ moves in $R^3$?

Let $C_1=(v_1,v_2,\ldots,v_{i-1},v_i)$ and $C_2=(v_1,v_2,\ldots,v_{i-1},v'_i)$ be two cycles that are drawn in $R^3$ in the shape of an unknot (not knotted) with straight line segments as their edges (...
Hooman's user avatar
  • 415
0 votes
0 answers
108 views

conformal deformation with fixed boundaries

For a flat plane with certain boundary, e.g., a rectangular patch, is it possible to conformally displace or deform such patch to a curved bump with exact same boundary? In this thesis, Dr. Keenan ...
Tony Dong's user avatar
  • 109
1 vote
0 answers
91 views

Representing a Pullback as an Infinite Matrix

Let $M$ and $N$ be manifolds and let $T: M \to N$ be a bijective map. Let $ \mathcal{F}(M,\mathbb{R})$ (resp.$ \mathcal{F}(N,\mathbb{R})$) be the space of all functions from $M$ (resp. $N$) to $\...
compmath's user avatar
2 votes
1 answer
586 views

Inverse Problem for Pullback

Let $M$ and $N$ be smooth manifolds and $T: M \to N$ be a smooth map. Let $ \mathcal{F}(M,\mathbb{R})$ (resp.$ \mathcal{F}(N,\mathbb{R})$) denote the space of smooth functions from $M$ (resp. $N$) ...
compmath's user avatar
8 votes
1 answer
1k views

Dubins car shortest paths: Decidable?

A Dubins car follows a Dubins path in $\mathbb{R}^2$, with constant wheel speed and limited turning radius. It is known that the shortest Dubins path in the absence of obstacles follows circular arcs ...
Joseph O'Rourke's user avatar
11 votes
5 answers
1k views

Segments of Voronoi Diagrams on smooth manifolds. Are they geodesics?

Let $S$ be a patch of a smooth 2-manifold in $\mathbb{R}^3$, and pick two distinct points $a,\ b \in S$. Let $c$ be the set of points on $S$ equidistant to $a$ and $b$, where distance is defined by ...
Max Suica's user avatar
  • 273
8 votes
2 answers
362 views

Computational methods for dealing with geometrically complicated solid boundaries in fluid-air interface problems

Hello, I am a PhD student who does not have extensive computational experience seeking advice from those experienced with computational modelling as to which method would be most appropriate for ...
Christopher's user avatar
4 votes
3 answers
919 views

Area-preserving map between rectangles and fat polygons

Are there any well-known continuous area-preserving maps between fat convex polygons and fat rectangles? Specifically, given a fat convex polygon $C$, is there a natural way to choose a fat rectangle ...
John Gunnar Carlsson's user avatar
6 votes
5 answers
4k views

Formulas for equidistant curves

I'm trying to draw on the computer a curve that keeps always the same distance(given as parameter) from a given curve. I know the formula for the given curve. I tried moving perpendicular to the first ...
Iulian Serbanoiu's user avatar