Everything about Penrose Triangle totally explained
[[Image:ImpossibleTriangleEastPerthedit gobeirne.jpg|thumb|200px|Impossible Triangle sculpture, East Perth, Western Australia. The structure is actually disjointed, and was photographed from one of the two spots that it was designed to be seen from. [http://im-possible.info/english/articles/real/real3.html More pictures from other angles.]
]]
The
Penrose triangle, also known as the
tribar, is an
impossible object. It was first created by the Swedish artist
Oscar Reutersvärd in
1934. The
mathematician Roger Penrose independently devised and popularised it in the
1950s, describing it as "impossibility in its purest form". It is featured prominently in the works of artist
M. C. Escher, whose earlier depictions of impossible objects partly inspired it.
The tribar appears to be a
solid object, made of three straight beams of square cross-section which meet pairwise at right angles at the vertices of the
triangle they form.
This combination of properties can't be realized by any 3-dimensional object. Nevertheless, there do exist 3-dimensional solid shapes each of which, when viewed from a certain angle, has the appearance of possessing all the qualities mentioned in the above paragraph. That is, it appears the same as the purple, green, and yellow 2-dimensional depiction of the Penrose triangle on this page.
M.C. Escher's
lithograph Waterfall depicts a watercourse that flows in a zigzag along the long sides of two elongated Penrose triangles, so that it ends up two stories higher than it began. The resulting waterfall, forming the short sides of both triangles, drives a
water wheel. Escher helpfully points out that in order to keep the wheel turning some water must occasionally be added to compensate for
evaporation.
There exists some terminological confusion over whether "Penrose triangle" refers to the 2-dimensional depiction of an impossible 3-dimensional object, or that impossible object itself. Philosophically, it's unclear what "that impossible object" refers to. Perhaps it refers to a set of conditions that can't be satisfied, perhaps to an abstract entitity that's depicted as satisfying those conditions (but doesn't actually satisfy them).
If a line is traced around the Penrose triangle, a 3-loop
Möbius strip is formed.
Other Penrose polygons
While it's possible to construct a Penrose triangle with other regular polygons to create a Penrose polygon, the visual effect isn't as striking, and as the sides increase, the image seems to be warped or twisted.
Image:Penrose_square.svg|Penrose square
Image:Penrose_pentagon.svg|Penrose pentagon
Image:Penrose_hexagon.svg|Penrose hexagon
Image:Penrose_octogon.svg|Penrose octagon
Further Information
Get more info on 'Penrose Triangle'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://penrose_triangle.totallyexplained.com">Penrose triangle Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |