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Strange definition of regularization of Operators

  1. Jun 17, 2008 #1
    surfing the web and arxiv i found the strange formula

    [tex] lnA= \frac{d^{n}}{ds^{n}} \frac{s^{n-1}}{n! A^{s}} [/tex]

    my question is .. where does this formula come from ??

    here 'n' is supposed to be a finite parameter we must define to avoid the divergences, is it valid for non-renormalizable or renormalizable theories ??
  2. jcsd
  3. Jun 17, 2008 #2


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    Whenever you want to do something like this, you must make a full citation of the source to put this into a proper context. Or else this may not make any sense.

  4. Jun 17, 2008 #3
  5. Jun 17, 2008 #4
    The [tex]-\lim_{s\to 0}[/tex] out in front is important.
  6. Jun 17, 2008 #5
    Formally taking a derivative wrt to [tex]A[/tex] on both sides should prove the identity to you.
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