Horizon, riverfront, visible horizon, spire, outline, ringstrasse,, skyscraper, cityscape, shape and profile In this page you can discover 13 synonyms, antonyms, idiomatic expressions, and related words for skyline, like: The term skyscraper originally applied to buildings of 10 to 20 stories, but by the late 20th century the term was used to describe high-rise buildings of unusual height, generally greater than 40 or 50 stories. As advances were made in construction, the qualifications to be considered a skyscraper grew to 150-meter (492-foot) minimum. How many floors makes a skyscraper?īuildings that ranged between 10 and 20 floors continued to be labeled as “skyscrapers” for years to come. , although a building with forty or more stories and taller than 150 metres (490 ft) is generally considered a skyscraper. There is no clear difference between a tower block and a skyscraper
Definition of skyscraper how to#
What is SKYSCRAPER? What does SKYSCRAPER? SKYSCRAPER meaning – How to pronounce SKYSCRAPER?Ģ5.0 similar questions has been found What is the difference between skyscraper and tower? It is one of the early skyscrapers which is visited by more than 5 million people each year. The skyscraper is the second highest structure in France and one of the most well known monuments in the world. The Eiffel Tower in Paris needs no introduction. Skyscrapers are very tall high-rise buildings. Modern sources currently define skyscrapers as being at least 100 metres (330 ft) or 150 metres (490 ft) in height, though there is no universally accepted definition. Is skyscraper a real word?Ī skyscraper is a tall continuously habitable building having multiple floors (archaic) A small sail atop a mast of a ship. A very tall building with a great number of floors. The Empire State Building is an example of a skyscraper. The definition of a skyscraper is a very tall building. In this page you can discover 11 synonyms, antonyms, idiomatic expressions, and related words for skyscraper, like: high-rise, glass-and-steel, skyline, tower, eyesore, tall building, minaret, building, steel-and-glass, modern building and 30-storey. A skyscraper essentially erases the sky by sticking out and blocking it. Today, it means to use a tool to apply pressure to something. The word scraper dates back to the Old Norse word skrapa, which means to erase. Rotman is probably assuming that $X$ is at least $T_1$.Skyscraper comes from the combination of the word sky and the word scraper. As Mike points out this is not true in all topological spaces. To do this you would want to show that given any open $U$ containing $y$ there is a smaller open set $V \subseteq U$ also containing $y$ but not containing $x$. To get that $P_y = 0$ you want to show that every section eventually restricts to $0$, hence $0$ is the only equivalence class in $T/\sim$. In other words, the map $(T/\sim) \to A$ defined by $(a, U) \mapsto a$ is a bijection.įor the other direction assume $y \neq x$. So we get that $(a, U) \sim (b, V)$ if and only if $a = b$. Conversely if $a = b$ then $a$ and $b$ restrict to the same element of $P(U \cap V)$ and we get that $(a, U) \sim (b, V)$. But the restrictions are the identity on $A$ so if this is true then $a = b$. Two such pairs $(a, U)$ and $(b, V)$ are equal if and only if $a$ and $b$ eventually restrict to the same place. Then the condition that the open sets contain $x$ means $P(U) = A$ for every $U$ that appears in our equivalence relation, so $T$ consists of pairs $(a, U)$ where $U$ is open and contains $x$ and $s \in A$. Now let $P$ be the skyscraper sheaf you've defined above and let $x$ be the point at which it's defined. In short this means that you can think of the elements of $P_x$ to be sections in some $P(U)$ and two sections are equal if and only if they eventually restrict to the same section. Note that if you think of $P(U)$ as actually being sections of a map then what I've written above is the definition of the equivalence relation that defines germs, but now I've written it in a way that it makes sense for any presheaf.ĭefine $P_x$ to be the equivalence classes $T/\sim$. Define a presheaf by $x_*A(U) = \begin|_V$. Here is Rotman's definition of the skyscraper sheaf: Let $A$ be an abelian group, $X$ a topological space, and $x \in X$.