Maps (on paper or on the screen) are flat surfaces; they require a transformation from the curved surfaceof the earth to the flat plane: a map projection.
纸上或屏幕上的地图是平面的；它们需要从地球的曲面向平面进行转换：地图投影。
2
Our everyday experience might itself be a holographic projectionof physical processes that take place on a distant, 2d surface.
我们的日常体验可能只是发生在遥远的二维表面上的物理过程的全息投射。
3
The size of the image can be adjusted simply by modifying the distance between the projector and the projectionsurface; the resulting image remains uniformly clear.