- #1
FredMadison
- 47
- 0
Hi!
The Dirac delta satisfies
[tex]\int dx f(x) \delta(x-a) = f(a)[/tex]
But how about
[tex]\int d^3x f(x) \delta^{(4)}(x-a)[/tex]
Here, x and a are four-momenta, and the integral is over the regular 3-dim momentum.
How does the delta behave here?
The Dirac delta satisfies
[tex]\int dx f(x) \delta(x-a) = f(a)[/tex]
But how about
[tex]\int d^3x f(x) \delta^{(4)}(x-a)[/tex]
Here, x and a are four-momenta, and the integral is over the regular 3-dim momentum.
How does the delta behave here?