{
  "aliases": null,
  "backlinks": null,
  "body": "\n## Definition\n\nA *Benz plane* is an incidence structure of points and circles that is a [[Möbius plane|DED008EJVH]], a [[Laguerre plane|F0JQ1TGKB0]] or a [[Minkowski plane|VB2D03PD9Y]].\n\n## Remarks\n\nThe three types differ in their parallelism of points.\nA Möbius plane has no parallel points, a Laguerre plane has one parallelism, and a Minkowski plane has two.\nIn each type, three pairwise non-parallel points lie on exactly one circle, and a touching axiom holds.\n\nExample: the real plane with a point $\\infty$ added, with circles and lines through $\\infty$ as circles, is a Möbius plane, hence a Benz plane.\n\nNon-example: a projective plane, with its lines as circles, is not a Benz plane.\nThree non-collinear points lie on no line, so the axiom on three points fails for each of the three types.\n\nThe classical Benz planes are the geometries of plane sections of a sphere, a cylinder and a hyperboloid of one sheet.\n",
  "commit": "ff8a40749dc16545e3d2fc637f6b0196e81d0bfa",
  "front": {
    "defines": "BG5A4CB6NB",
    "kind": "definition",
    "msc": [
      "51B05",
      "51B10"
    ],
    "name": "Benz plane",
    "sources": [
      {
        "url": "https://en.wikipedia.org/wiki/Benz_plane"
      }
    ],
    "tag": "8NCGCJ2YBH",
    "uses": [
      "DED008EJVH",
      "F0JQ1TGKB0",
      "VB2D03PD9Y"
    ]
  },
  "kind": "definition",
  "link": "https://tamnd.github.io/math2/node/8NCGCJ2YBH/",
  "links": [
    {
      "field": "defines",
      "target": "BG5A4CB6NB"
    },
    {
      "field": "uses",
      "target": "DED008EJVH"
    },
    {
      "field": "uses",
      "target": "F0JQ1TGKB0"
    },
    {
      "field": "uses",
      "target": "VB2D03PD9Y"
    }
  ],
  "markdown": "https://tamnd.github.io/math2/node/8NCGCJ2YBH.md",
  "msc": [
    "51B05",
    "51B10"
  ],
  "name": "Benz plane",
  "prov": null,
  "role": "",
  "source": "https://github.com/tamnd/math2/blob/main/nodes/8NC/8NCGCJ2YBH.md",
  "status": null,
  "tag": "8NCGCJ2YBH",
  "uri": "m2://8NCGCJ2YBH",
  "url": "https://tamnd.github.io/math2/wiki/benz-plane-definition/",
  "writing": {
    "tag": "8NCGCJ2YBH",
    "kind": "definition",
    "level": "W0",
    "next": [
      {
        "what": "an inventory row",
        "note": "the row of the inventory that the node accounts for",
        "have": 0,
        "want": 1
      },
      {
        "what": "a source with a locator",
        "have": 0,
        "want": 1
      }
    ]
  }
}
