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Miklós Schweitzer
2015 Miklos Schweitzer
7
7
Part of
2015 Miklos Schweitzer
Problems
(1)
Covering of the unit sphere
Source: Miklos Schweitzer 2015, problem 7
3/31/2016
We call a bar of width
w
{w}
w
on the surface of the unit sphere
S
2
{\Bbb{S}^2}
S
2
, a spherical segment, centered at the origin, which has width
w
{w}
w
and is symmetric with respect to the origin. Prove that there exists a constant
c
>
0
{c>0}
c
>
0
, such that for any positive integer
n
{n}
n
the surface
S
2
{\Bbb{S}^2}
S
2
can be covered with
n
{n}
n
bars of the same width so that any point is contained in no more than
c
n
{c\sqrt{n}}
c
n
bars.
combinatorics
geometry