Covering Sphere w/ Disks: Min Required Radius k

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In summary, the conversation discusses the minimum number of disks needed to perfectly cover a sphere with a radius k times the radius of the disks. There is a mention of the disk covering problem and the possibility of using the number of steradian needed to cover a sphere. There is also a question about a 3-dimensional complex space with an orthogonal counterpart to the traditional complex plane. The conversation ends with a debate about whether 4 or 2k^2 disks are needed to cover the sphere without distortion.
  • #1
Ynaught?
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What is the minimum number of disks required to perfectly cover a sphere with a radius k number of times the radius of the disks?
 
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  • #2
1/0.
 
  • #3
Werg22, he said "sphere", not "ball".
 
  • #4
Thanks Wergs22 and HallsofIvy,

...but I was looking for a solution more akin to the disk covering problem http://mathworld.wolfram.com/DiskCoveringProblem.html" but for a sphere rather than the complex plane extended over a sphere. Maybe if we consider the number of steradian needed to cover a sphere?

As an aside, the Riemann Sphere brings up another question... Is there a 3 dimensional complex space where the traditional complex plane has an orthogonal counterpart sharing the same Real axis?
 
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  • #5
Since the Surface area of a sphere is 4*pi*r^2 and the area of a disc is pi*r^2 wouldn't you need just 4? This is assuming of course you could manipulate the shape of the discs without changing their area.
 
  • #6
Hey Diffy, I came to the same conclusion for the case where the radius of the sphere and the radius of the disks are equal. And when the radius of the sphere is k times the radius of the disks the number is 2k^2. But I can't see how four disks can cover a sphere without being distorted, in which case, the disks are no longer disks...
 

1. What is "Covering Sphere w/ Disks: Min Required Radius k"?

"Covering Sphere w/ Disks: Min Required Radius k" is a mathematical problem that involves finding the smallest possible radius of a sphere that can be covered by a certain number of disks. The disks must be placed on the surface of the sphere and must not overlap.

2. What is the significance of this problem?

This problem has applications in various fields, including computer science, physics, and geometry. It can be used to optimize the placement of sensors or antennas on a sphere, or to determine the minimum number of radar stations needed to cover a certain area.

3. How is the minimum required radius calculated?

To calculate the minimum required radius, a mathematical formula is used that takes into account the number of disks and their sizes. This formula is based on the concept of packing density, which is the ratio of the total area covered by the disks to the surface area of the sphere.

4. Is there a solution for every number of disks?

Yes, there is a solution for every number of disks. However, it may not always be a whole number and may require rounding up or down to find the optimal radius. In some cases, the solution may also involve using different sizes of disks.

5. Are there any real-world examples of this problem?

Yes, there are many real-world examples of this problem. One example is the placement of satellite dishes on the surface of a communication satellite. Another example is in the design of spherical mirrors for telescopes, where the disks represent the individual mirror segments.

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