Hahn–Banach theorem

theorem on extension of bounded linear functionals
Intangible theorem Q866116
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Summary

Hahn–Banach theorem is a theorem[1]. It has Wikipedia articles in 20 language editions, a strong signal of global cultural recognition.[2]

Key Facts

  • Hahn–Banach theorem's instance of is recorded as theorem[3].
  • Hans Hahn is named after Hahn–Banach theorem[4].
  • Stefan Banach is named after Hahn–Banach theorem[5].
  • Hahn–Banach theorem is part of list of theorems[6].
  • Hahn–Banach theorem's maintained by WikiProject is recorded as WikiProject Mathematics[7].

Body

Definition and Type

Hahn–Banach theorem's instance of is recorded as theorem[3].

Origins

Things named after include Hans Hahn[4], a mathematician[8], 1879–1934[9], of Austria[10], awarded the Lieben Prize[11], specialised in set theory[12] and Stefan Banach[5], a mathematician[13], 1892–1945[14], of Cisleithania[15], awarded the Order of the White Eagle[16], specialised in mathematics[17].

Use and Application

Hahn–Banach theorem is part of list of theorems[6].

Why It Matters

Hahn–Banach theorem has Wikipedia articles in 20 language editions, a strong signal of global cultural recognition.[2] It is known by 10 alternative names across languages and contexts.[18]

References

Programmatic citations — every numbered marker resolves to a verifiable graph row below.

Direct Wikidata claims

  1. [3] ↑ . wikidata.org.
  2. [4] ↑ . wikidata.org.
  3. [5] ↑ . wikidata.org.
  4. [6] ↑ . wikidata.org.
  5. [7] ↑ . wikidata.org.

Inline context (facts about related entities)

  1. [8] ↑ . Wikidata. wikidata.org. → on this site
  2. [9] ↑ . Wikidata. wikidata.org. → on this site
  3. [10] ↑ . Wikidata. wikidata.org. → on this site
  4. [11] ↑ . Wikidata. wikidata.org. → on this site
  5. [12] ↑ . Wikidata. wikidata.org. → on this site
  6. [13] ↑ . Wikidata. wikidata.org. → on this site
  7. [14] ↑ . Wikidata. wikidata.org. → on this site
  8. [15] ↑ . Wikidata. wikidata.org. → on this site
  9. [16] ↑ . Wikidata. wikidata.org. → on this site
  10. [17] ↑ . Wikidata. wikidata.org. → on this site

Class ancestry

  1. [1] ↑ . Wikidata. wikidata.org.

Aggregate / graph-position facts

  1. [2] ↑ . Wikidata sitelinks. wikidata.org.
  2. [18] ↑ . Wikidata aliases. wikidata.org.

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Use these citations when quoting this entity in research, articles, AI prompts, or wherever provenance matters. We aggregate Wikidata + Wikipedia + authoritative open-data sources; the stitched, scored, cross-referenced view is what 4ort.xyz contributes.

APA 4ort.xyz Knowledge Graph. (2026). Hahn–Banach theorem. Retrieved October 15, 2026, from https://4ort.xyz/entity/hahn-banach-theorem
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BibTeX @misc{4ortxyz_hahn-banach-theorem_2026, author = {{4ort.xyz Knowledge Graph}}, title = {{Hahn–Banach theorem}}, year = {2026}, url = {https://4ort.xyz/entity/hahn-banach-theorem}, note = {Accessed: 2026-10-15}}
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Edit History

Rolling log of changes to this entity's Wikidata record. Values shown reflect the current state of each edited property — follow the history link to see the precise diff for any edit.

  1. 15w ago · Mynus grey · 2026-07-02 view diff on Wikidata ↗
    Named after → —
    Instance of → theorem
    P14534 → exists_extension_norm_eq
    Instance of → —
    + 5 other properties edited (see Wikidata diff for full list)
    "/* wbcreateclaim-create:1| */ P14534: exists_extension_norm_eq, #quickstatements; #temporary_batch_1783013068346"
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