Permittivity of vacuum

{
  "id": "MLC-T-CHM-008676",
  "term": "Permittivity of vacuum",
  "field": "Chemistry",
  "definition": "A fundamental constant, written ε₀, that relates electric displacement to electric field strength in a vacuum and equals 1/(μ₀c²), with c the speed of light. Its value is 8.8541878128 × 10⁻¹² farads per metre. Since the 2019 SI revision it is no longer exact, because μ₀ is now measured, but it matches the earlier exact value to better than one part in a billion.",
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "permeability of vacuum"
  ],
  "references": [
    "CODATA 2006 (https://doi.org/10.1103/RevModPhys.80.633)",
    "Green Book, 2nd ed., p. 14 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/permittivity-of-vacuum/"
}