# Above and below

"Above" and "below" denote different directions in different places on earth.

Above and below are opposite relative locations. As a rule, they refer to the direction of the gravitational acceleration and the physical orientation of the person in the earth's gravitational field . Below denotes places that are in the effective direction of the weight force . Above are places in the direction against the weight.

Understood as directions, top and bottom correspond to the plumb direction (vertical) running through a given location . Due to the spherical shape of the earth, the vertical lines of the gravitational field are not parallel to each other; therefore every place has its own vertical. For people on the opposite side of the earth , the directions above and below are even completely reversed. In addition, since the earth rotates and is not a perfect sphere , the plumb line generally does not point exactly to the center of the earth . In the geocenter itself there is no longer any “down” and every direction is “up”. Even in a state of free fall , for example in a parabolic flight or on board the ISS , there is weightlessness and there is no up and down within this system.

In addition to left and right and front and rear, they form one of the three dimensions of Euclidean space and thus serve people in egocentric (as opposed to allocentric ) societies for spatial orientation .

## Objects

"Above" (red arrow) in a drawing

Objects can also have a top and bottom, regardless of their actual position, which results from their design or application. For example, the opening of a bottle is always its top end , even if the bottle is on a flat surface and both ends are on the same level. This is because it was designed to stand with its lower part (floor) on a flat surface without losing its contents, even if the opening is not closed.

Papers, drawings and similar things are also assigned a top and bottom. This also applies when they lie flat on a table. When the page is right side up, the bottom is the side closest to the viewer; the side furthest from the viewer at the top .

## society

The terminology is also applied to the social structure, in the sense of an upper and a lower class, whereby values ​​such as income , education , origin or character are used as a classification criterion .

## geography

In geography there is a consistent convention that the north side is on top and the south side is on the bottom on map material . Some historical maps are an exception to this. A north orientation is not possible for maps that show the north or south pole area centrally. Here the prime meridian is often oriented downwards on Arctic maps, but upwards on Antarctic maps.

Rivers have an upper and a lower course , which can also give the region its name, such as the location on the Main near Lower and Upper Franconia or the location on the Danube near Upper and Lower Bavaria .

In the case of neighboring towns with names such as Oberammergau (837 m above sea level) and Unterammergau (836 m above sea level), the name usually indicates which place is higher and which is lower.