{
  "aliases": null,
  "backlinks": [
    {
      "field": "about",
      "target": "3VRZ80X45P"
    },
    {
      "field": "uses",
      "target": "3VRZ80X45P"
    },
    {
      "field": "specializes",
      "target": "7VPJWF0AZ7"
    },
    {
      "field": "defines",
      "target": "A2WHCVP6JN"
    }
  ],
  "body": "\n## Summary\n\nThe germ of an analytic set at a point $a$ records the shape of a [[complex analytic variety|GB7M582M5Y]] arbitrarily close to $a$.\nIt forgets the rest of the set.\nTwo analytic sets have the same germ at $a$ when they coincide on some neighbourhood of $a$.\nGerms of analytic sets at $a$ correspond to radical ideals of the ring of [[germs of holomorphic functions|7PJ8KVZZCQ]] at $a$.\nThis makes local analytic geometry a branch of commutative algebra.\n\n## Explanations\n\n### L1 human\n\nZoom in on an analytic set at one point and keep only what is visible at every scale.\nFor instance, the curve $\\set{z_2^2 = z_1^2(1 + z_1)}$ in $\\C^2$ is connected and irreducible as a whole, but its germ at the origin looks like two smooth branches crossing.\nFar away points, such as other components of the set, do not affect the germ.\n",
  "commit": "ff8a40749dc16545e3d2fc637f6b0196e81d0bfa",
  "front": {
    "kind": "concept",
    "msc": [
      "32B10",
      "32B05"
    ],
    "name": "Germ of an analytic set",
    "sources": [
      {
        "url": "https://en.wikipedia.org/wiki/Complex_analytic_variety"
      }
    ],
    "specializes": [
      "VZXF7RNFKS"
    ],
    "tag": "Q9B74BYZ8C"
  },
  "kind": "concept",
  "link": "https://tamnd.github.io/math2/node/Q9B74BYZ8C/",
  "links": [
    {
      "field": "specializes",
      "target": "VZXF7RNFKS"
    }
  ],
  "markdown": "https://tamnd.github.io/math2/node/Q9B74BYZ8C.md",
  "msc": [
    "32B10",
    "32B05"
  ],
  "name": "Germ of an analytic set",
  "prov": null,
  "role": "",
  "source": "https://github.com/tamnd/math2/blob/main/nodes/Q9B/Q9B74BYZ8C.md",
  "status": null,
  "tag": "Q9B74BYZ8C",
  "uri": "m2://Q9B74BYZ8C",
  "url": "https://tamnd.github.io/math2/wiki/germ-of-an-analytic-set/",
  "writing": {
    "tag": "Q9B74BYZ8C",
    "kind": "concept",
    "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
      }
    ]
  }
}
