Can Dyadic Squares Approximate the Area of a Unit Disc with Minimal Overlap?

In summary, the unit disc contains finitely many dyadic squares whose total area exceeds pi - epsilon, and which intersect each other only along their boundaries.
  • #1
JG89
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Homework Statement



Given [tex] \epsilon > 0 [/tex], show that the unit disc contains finitely many dyadic squares whose total area exceeds [tex] \pi - \epsilon [/tex], and which intersect each other only along their boundaries.


Homework Equations





The Attempt at a Solution



I've tried to solve this two ways. First, by finding a series of dyadic squares whose area converges to pi. But I realized it would be very complicated to show that these squares are all contained in the unit disc, and in addition, intersect each other only along their boundaries.

For my second method, I thought that if I could prove the original statement, but for the portion of the semi-circle in the first-quadrant, which is described by the equation [tex] \sqrt{1 - x^2} [/tex]. I thought I could take a look at the Riemann sums and choose my partition cleverly so that it's only dyadic squares that are approximating the area under the graph. But then I realized that these dyadic squares would also intersect some other dyadic square at only a vertex, which isn't allowed by this problem. So I dropped this idea too.


One thing that I proved, which may help with this, is that for any two dyadic squares of the same size, they are either identical, intersect each other along an edge, intersect at a vertex, or are completely distinct.

Any ideas?
 
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  • #2
Surely intersecting only at a vertex is allowed by "intersecting only along their boundaries", since the vertex is part of the boundary. From a practical perspective you'd be doing this to find the area of the circle, so you'd just want the area of overlap to be zero.

I don't see what's wrong with your second method.
 
  • #3
Nice! I had a lot of hope in my second method, as that was turning out some interesting results.

Time to get back to work...thanks for the reply :)
 

Related to Can Dyadic Squares Approximate the Area of a Unit Disc with Minimal Overlap?

1. What is a unit disc?

A unit disc is a mathematical concept that refers to a circle with a radius of 1 unit. It can also be thought of as a disk or a two-dimensional shape with a circular boundary.

2. What are dyadic squares?

Dyadic squares are a type of square where each side is a power of 2. In other words, the length of each side is a multiple of 2, such as 2, 4, 8, 16, and so on.

3. How are unit discs and dyadic squares related?

Unit discs and dyadic squares are often used in conjunction to describe a specific type of tiling pattern. The unit discs are arranged in a way that creates a repeating pattern of dyadic squares.

4. What is the significance of unit discs and dyadic squares in mathematics?

Unit discs and dyadic squares are important in various mathematical fields, such as geometry and number theory. They have applications in areas such as tiling, fractals, and digital signal processing.

5. Can unit discs and dyadic squares be extended to higher dimensions?

Yes, the concept of unit discs and dyadic squares can be extended to higher dimensions. In three dimensions, for example, we can have unit spheres and dyadic cubes.

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