The Planiverse: Computer Contact with a Two-Dimensional World is a 1984 novel by mathematician and computer scientist A. K. Dewdney.
Dewdney tells of having his programming class work on a project to simulate the physics of a two-dimensional, planar universe — only to quickly realise that their software has somehow connected to an inhabitant of an actual circular planet, Arde, able to watch him on their displays and communicate through a simple text interface. YNDRD, or "Yendred", hears their messages as voices in his head, and is very concerned by the implications for his sanity and his personal search for meaning in existence.
While largely obscure compared to its more-accessible inspiration Flatland, its premise as an imaginary universe explored through an intricate computer simulation was an influence on the Creatures games.
Tropes:
- Ascend to a Higher Plane of Existence: Literally. Yendred's search for meaning takes him to Vanizla to study under a guru who lives atop the highest mountain on the continent. Dewdney's students watch him attain enlightenment, whereupon with little explanation he fondly bids them farewell, consciously terminates their telepathic contact, and walks sideways out of the Planiverse.
- Audience Surrogate: A. K. Dewdney and his computer science students.
- Author Avatar: Yendred, rather than A. K. Dewdney's eponymous character. His motivations seeking meaning deeper than science that paralleled the author's own.
- Beneath the Earth: Ardeans live in underground hobbit-holes to avoid the rain — on a circular planet, there are no rivers, only flash floods. The one surface building is directly atop the continental divide.
- Bizarre Alien Biology: Yendred's digestive system is a zipper and runs between the two halves of his brain. When he swallows, his esophagus unzips to pass each bite into his stomach and reconnects behind it, and then it proceeds through his intestines the same way. The zipper keeps him from being split in half.
- Fantasy Counterpart Culture: Arde has a single known continent, Ajem Kollosh. Yendred's homeland, Punizla, on the western end, is broadly similar to industrialised Europe; Vanizla, in the east, is analogous to an orientalised view of Indian and Himalayan cultures.
- Hermit Guru: Yendred seeks Drabk, who lives on the highest peak of Ajem Kollosh and is said to possess knowledge of "the Beyond". He teaches Yendred how to walk "sideways" out of the Planiverse, but also how to cut contact with Dewdney's students.
- Human Aliens: Yendred is about as close to human as could realistically exist in two dimensions. He's bilaterally symmetric. He has a head containing his eyes and mouth, a complete gastrointestinal tract, two legs, recognisable jointed arms and hands, etc. He even has a gender! Never mind that he has four arms total, his mouth is between his eyes, and there's even more Bizarre Alien Biology underneath.
- Minovsky Physics: Much of the story is a framing device to explore the worldbuilding of a two-dimensional universe more realistically than a satirical allegory like Flatland. In general, Dewdney makes Arde broadly like Earth, with most of the differences consequences of its geometry. Having only two dimensions means that gravity, light, and sound dissipate in strength proportionately to 1/r, rather than 1/r2, which affects the atomic and molecular structure for the entire Ardean periodic table. (Dewdney included an appendix to show his work for everything he couldn't fit into the novel itself.)
- Philosophical Novel: Most of the story consists of Dewdney's student interrogating Yendred about how his world works, while Yendred seeks answers about the meaning of life from the otherworldly beings talking in his head (only to find they don't know much more than he does). His quest for enlightenment analogises Dewdney's own conversion to Sufism.
- Sdrawkcab Name: Try spelling "Dewdney" backwards.
- Translation Convention: Whatever fluke allowed the computer to contact Yendred also translates between English and his unnamed language, in somewhat scrambled sentences. His actual language is spoken with hisses, squeaks, and choking noises.
