Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Textbook definition a c-number

  1. Sep 6, 2005 #1
    Hello everyone--I was hoping someone could give (or refer to) a textbook definition of a [tex]c[/tex]-number, as used in the context of quantum field theory.

    Does this refer to a commuting number? I've also read it referring to a classical quantity. classical quantity, from a not-very-reputable source. (Though are these the same?)

    If the 'c' refers to commuting, when I read something like "...spinors are anti-commuting (c-numbers)." (Bailin and Love, SUSY book) Does this mean that spinors are anti-commuting objects composed of commuting numbers? (It certainly doesn't mean that the spinors themselves are commuting...)

  2. jcsd
  3. Sep 6, 2005 #2
    C-number usually refers to "complex" number. At least that is all I have ever seen it used as.
  4. Sep 6, 2005 #3


    User Avatar
    Science Advisor

  5. Sep 8, 2005 #4
    c-number is really defined as a classical number. it is not an operator or

    anticommuting number is Grassmann number used in the functional integral
    representation of fermionic field.

    Often the Grassman number is not called c-number, maybe someone can call
    Grassmann number as c-number.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?