Word.ws English Dictionary

bra-ket

bra-ket noun: the scalar product of two vectors (and optionally an operator), in Hilbert space, where the left (row) vector is a bra and the right (column) vector is a ket. Symbolised by ⟨...|...⟩ (bra and ket only) or ⟨...|...|...⟩ (bra, operator, ket).

Noun

bra-ket (plural bra-kets)

  1. The scalar product of two vectors (and optionally an operator), in Hilbert space, where the left (row) vector is a bra and the right (column) vector is a ket. Symbolised by ⟨...|...⟩ (bra and ket only) or ⟨...|...|...⟩ (bra, operator, ket).

Forms of bra-ket

pluralbra-kets

Origin of bra-ket

Concatenation of the terms bra and ket, which were introduced in 1939 and in turn derive from the splitting of the English word bracket.

Questions about bra-ket

What does bra-ket mean?
Bra-ket means the scalar product of two vectors (and optionally an operator), in Hilbert space, where the left (row) vector is a bra and the right (column) vector is a ket. Symbolised by ⟨...|...⟩ (bra and ket only) or ⟨...|...|...⟩ (bra, operator, ket).
What part of speech is bra-ket?
Bra-ket is a noun.
What is the plural of bra-ket?
The plural of bra-ket is bra-kets.

Words near bra-ket in the dictionary

  1. bra chains
  2. bra insert
  3. bra inserts
  4. bra-burner
  5. bra-burning
  6. bra-ket
  7. bra-kets
  8. BRAA
  9. braaam
  10. braaams
  11. braai

Source and license

Adapted from Wiktionary: bra-ket (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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