Personal dome

Illustration of the personal dome concept in Walter Bilsin's Flat Earth Dome Model

The personal dome, dome of vision, or azimuthal grid of vision is a nonsensical and ad hoc concept used by flerfs to "explain" observations of the celestial sphere that are incompatible with flat Earth.

The concept suggests that all observers each have a dome-shaped membrane of arbitrary radius with them at the centre, onto which all celestial phenomena are "projected" in exact accordance with what the globe predicts from their location. The personal dome is similar to the alt-az grid used by planetarium software.

To at least some degree, it is an extension of the concept of flerfspective, but adherents usually believe that light-bending is involved too.

Problems

Its more difficult to identity what is not problematic with the concept.

Unfalsifiable

The personal dome is, by its own nature, unfalsifiable (and therefore pseudoscience). The required light-bending lacks any coherent mechanism, but the concept technically cannot be falsified until every conceivable mechanism is falsified, of which there are virtually infinite. The unfalsifiablility also means the personal dome is not exclusive to flat Earth models; it could be used in exactly the same way to rescue the theory of a banana-shaped Earth.