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Vacuum permittivity

Absolute dielectric permittivity of free space

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Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionJul 28, 2026
Entity authoritySource title only
Source-derived summary

Vacuum permittivity, commonly denoted ε0, is the value of the absolute dielectric permittivity of classical vacuum. It may also be referred to as the permittivity of free space, the electric constant, or the distributed capacitance of the vacuum. It is an ideal (baseline) physical constant. Its CODATA value is:

Editorial summary

This brief starts where responsible research should: with the source description of “Vacuum permittivity” as absolute dielectric permittivity of free space. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current 49-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. The account is most persuasive where Vacuum, permittivity and Absolute can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as absolute dielectric permittivity of free space. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Jul 28, 2026.

Critical limits

The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

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  2. Expand the search: follow Vacuum permittivity primary sources, Vacuum permittivity archive and Vacuum research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

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Source & attribution

This entry incorporates text from “Vacuum permittivity” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.