- #1
kassem84
- 13
- 0
The integral:
[itex]\int[/itex]d[itex]^{3}k[/itex][itex]\frac{1}{k^{2}+m^{2}}[/itex]
is linearly divergent i.e. ultraviolet divergent.
However, If one performs dimensional regularization to the above integral:
[itex]\frac{1}{(2\pi)^d}[/itex][itex]\int[/itex]d[itex]^{d}k[/itex][itex]\frac{1}{k^{2}+m^{2}}[/itex]=[itex]\frac{(m^{2})^{d/2-1}}{(4\pi)^{d/2}}[/itex][itex]\Gamma(1-d/2)[/itex]
As you can notice that the poles of the Gamma function are for even dimension i.e. d=2,4,6..etc and that the integral is convergent for d=3 for example!
What is the reason behind this convergence? Is it due to the Veltman's formula:
[itex]\frac{1}{(2\pi)^d}[/itex][itex]\int[/itex]d[itex]^{d}k[/itex][itex] (k^{2})^{n-1}[/itex] = 0, for n=0,1,2,..
I am dealing with a divergent integral of power divergence (ultraviolet, quadratic, quartic,... and no logarithmic divergence). Do you advise me to use dimensional regularization or other methods?
[itex]\int[/itex]d[itex]^{3}k[/itex][itex]\frac{1}{k^{2}+m^{2}}[/itex]
is linearly divergent i.e. ultraviolet divergent.
However, If one performs dimensional regularization to the above integral:
[itex]\frac{1}{(2\pi)^d}[/itex][itex]\int[/itex]d[itex]^{d}k[/itex][itex]\frac{1}{k^{2}+m^{2}}[/itex]=[itex]\frac{(m^{2})^{d/2-1}}{(4\pi)^{d/2}}[/itex][itex]\Gamma(1-d/2)[/itex]
As you can notice that the poles of the Gamma function are for even dimension i.e. d=2,4,6..etc and that the integral is convergent for d=3 for example!
What is the reason behind this convergence? Is it due to the Veltman's formula:
[itex]\frac{1}{(2\pi)^d}[/itex][itex]\int[/itex]d[itex]^{d}k[/itex][itex] (k^{2})^{n-1}[/itex] = 0, for n=0,1,2,..
I am dealing with a divergent integral of power divergence (ultraviolet, quadratic, quartic,... and no logarithmic divergence). Do you advise me to use dimensional regularization or other methods?