Closed Surfaces
A closed surface is a surface that is compact and without boundary. Examples are spaces like the sphere, the torus and the Klein bottle. Examples of non-closed surfaces are: an open disk, which is a sphere with a puncture; a cylinder, which is a sphere with two punctures; and the Möbius strip.
Read more about this topic: Surface
Famous quotes containing the words closed and/or surfaces:
“She was so overcome by the splendor of his achievement that she took him into the closet and selected a choice apple and delivered it to him, along with an improving lecture upon the added value and flavor a treat took to itself when it came without sin through virtuous effort. And while she closed with a Scriptural flourish, he “hooked” a doughnut.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“Footnotes are the finer-suckered surfaces that allow tentacular paragraphs to hold fast to the wider reality of the library.”
—Nicholson Baker (b. 1957)