Solving Coverage with Sets: Min Info Needed?

  • Thread starter Thread starter axelmorack
  • Start date Start date
  • Tags Tags
    Sets
AI Thread Summary
The discussion centers on the challenge of maximizing floor coverage with various oddly shaped flat objects while ensuring minimal overlap between any two objects. The participants express that the provided information is insufficient to derive a definitive solution, particularly due to the lack of uniformity in object shapes. They suggest exploring covering theorems, such as the 5-r covering theorem, Vitali, or Besicovitch theorems, for potential insights. The conversation highlights the complexity of the problem, especially in the absence of symmetry or regularity among the shapes. Overall, the consensus is that more specific information or structure is needed to effectively address the coverage issue.
axelmorack
Messages
10
Reaction score
0
A question about sets??

I have a number of weird shaped flat objects. I am interested in covering as much of the floor as I can. After placing the objects on the floor, the only info I have is:

Choosing any two objects on the floor, the overlap between them is at a minimum possible.

What can I say about the coverage? Do I have too little information to say anything?
 
Mathematics news on Phys.org


Too little info, but the general subjects you're interested in are tilings and tesselations.

http://en.wikipedia.org/wiki/Tessellation

http://en.wikipedia.org/wiki/Tiling_by_regular_polygons

An interesting historical aside is the discovery of new classes of tesselations in the 70's by an amateur mathematician, a housewife with a high school education. Her name is Marjorie Rice. She read a Scientific American article on tesselations and started working with them in her spare time. She'd work out her formulas on her kitchen counter and cover up her work whenever anyone came into the kitchen.

She eventually developed her own system of notation, sent her results off to the local university, and was recognized for having made brand new mathematical discoveries.

http://en.wikipedia.org/wiki/Marjorie_Rice

Her website is here.

http://tessellations.home.comcast.net/~tessellations/

You didn't mention if your flat objects are all the same shape or not. That's going to make a huge difference in being able to solve the problem.
 
Last edited by a moderator:
Last edited:


Perhaps you are interested in covering theorems? You may start with the 5-r covering theorem (it's one of the most basic and easier to understand), then maybe the Vitali or Besicovitch covering theorem, though they get very technical.

Though your phrasing makes me think that you have some kind of optimization in mind, in which case if there isn't any symmetry or regularity in your shapes, then there wouldn't be a quick solution.
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Is it possible to arrange six pencils such that each one touches the other five? If so, how? This is an adaption of a Martin Gardner puzzle only I changed it from cigarettes to pencils and left out the clues because PF folks don’t need clues. From the book “My Best Mathematical and Logic Puzzles”. Dover, 1994.
Thread 'Imaginary Pythagoras'
I posted this in the Lame Math thread, but it's got me thinking. Is there any validity to this? Or is it really just a mathematical trick? Naively, I see that i2 + plus 12 does equal zero2. But does this have a meaning? I know one can treat the imaginary number line as just another axis like the reals, but does that mean this does represent a triangle in the complex plane with a hypotenuse of length zero? Ibix offered a rendering of the diagram using what I assume is matrix* notation...
Back
Top