動画 1 8月 3,995 リアクション

spring-of-mathematics:

Mathematically Correct Breakfast - How to Slice a Bagel into Two Linked Halves. If a torus is cut by a Möbius strip it will split up into to interlocking rings.

It is not hard to cut a bagel into two equal halves which are linked like two links of a chain. Figure 1:

  1. To start, you must visualize four key points.  Center the bagel at the origin, circling the Z axis. A is the highest point above the +X axis.  B is where the +Y axis enters the bagel. C is the lowest point below the -X axis.  D is where the -Y axis exits the bagel.
  2. These sharpie markings on the bagel are just to help visualize the geometry and the points.  You don’t need to actually write on the bagel to cut it properly.
  3. The line ABCDA, which goes smoothly through all four key points, is the cut line.  As it goes 360 degrees around the Z axis, it also goes 360 degrees around the bagel.
  4. The red line is like the black line but is rotated 180 degrees (around Z or through the hole). An ideal knife could enter on the black line and come out exactly opposite, on the red line. But in practice, it is easier to cut in halfway on both the black line and the red line. The cutting surface is a two-twist Mobius strip; it has two sides, one for each half.
  5. After being cut, the two halves can be moved but are still linked together, each passing through the hole of the other.

It is much more fun to put cream cheese on these bagels than on an ordinary bagel. In additional to the intellectual stimulation, you get more cream cheese, because there is slightly more surface area.
Topology problem: Modify the cut so the cutting surface is a one-twist Mobius strip. (You can still get cream cheese into the cut, but it doesn’t separate into two parts). See more at: Mathematically Correct Breakfast: How to Slice a Bagel into Two Linked Halves by George W. Hart.

Images: How to Slice a Bagel into Two Linked Halves by George W. Hart - Cutting bagels into linked halves on Mathematica. - Interlocking Bagel Rings

Maybe, that’s one of the reasons why I love bagel :)

動画 15 7月
引用 27 6月 568 リアクション
「休日とか何してるの?」
「最近は夕方まで reblog してます! 夜に自己嫌悪です!」
画像 17 6月 18 リアクション rnelty:

アイドルマスター、アイドルマスターシンデレラガールズ、島村卯月、mokufuu、ブラ、おへそ、バイブ、パンツ、ベッド、スカート、オープンシャツ、open clothes、一人、下着、乳、乳首、パンツ内バイブ、女一人、学校制服、寝そべり、ブラ引っ張り、枕、栗毛、汗、背中で、赤面、長い髪、閲覧者を見ている、黒い瞳 | Sankaku Channel
画像 17 6月 1,814 リアクション

(出典: grimacetif)

画像 17 6月 140 リアクション
画像 17 6月 165 リアクション rnelty:

【非エロ微エロ】艦隊これくしょん~艦これ~【画像】 その5 - 二次萌エロ画像ブログ
画像 17 6月 185 リアクション rnelty:

shibuya rin (idolmaster and idolmaster cinderella girls) drawn by paopao - Danbooru
画像 1 6月 71 リアクション tsukage:

「離島棲鬼ちゃん~」/「Walzrj@W18」の作品 [pixiv] #pixitail
via Deiclipse.
画像 20 5月 134 リアクション

Design crafted by Prashanth Kamalakanthan. Tumblrによって提供されています.