Calculate between [-epsilon,epsilon]

[alejandrito29]

i need to integrate

-(p(y)f(y)')'=m^2w(y)f(y)
where
p(y)=e^{4ky}(1-4ak^2) and w=-4ae^{2y}k\delta(y)

but y between [0,infinity[

¿i calculate between \int^{epsilon}_0? or ¿i calculate between [-epsilon,epsilon]?

but, what is??

\int^{\epsilon}_0(p(y)f(y)')'dy

whit f is not continuous in zero


the result is
f(+\epsilon)=-\frac{m^24akf(0)}{1-4ak^2}

 

[HallsofIvy]

i need to integrate

-(p(y)f(y)')'=m^2w(y)f(y)
where
p(y)=e^{4ky}(1-4ak^2) and w=-4ae^{2y}k\delta(y)

but y between [0,infinity[

¿i calculate between \int^{epsilon}_0? or ¿i calculate between [-epsilon,epsilon]?

I have no idea what you are talking about. What are yu integrating? If you are talking about the integral above, if it is given as a definite integral, you use whatever limits of integration are given. If it is given as an indefinite integral (anti-derivative) you do not use any limits of integration.

but, what is??

\int^{\epsilon}_0(p(y)f(y)')'dy

By the Fundamental Theorem of Calculus, the integral of the derivative of any function is that function:
\int^{\epsilon}_0(p(y)f(y)')'dy= p(y)f(y)'

whit f is not continuous in zero

If f is not continuous at zero, then it is not differentiable at zero and the integrand above does not exist at 0.

the result is
f(+\epsilon)=-\frac{m^24akf(0)}{1-4ak^2}

Since you haven't actually stated what the problem is, I have no idea whether that is correct or not.

 

[alejandrito29]

Since you haven't actually stated what the problem is, I have no idea whether that is correct or not.

f(+\epsilon)=-\frac{m^24akf(0)}{1-4ak^2}
this problem is in eq. (3)-(6)...(10)
of:
http://arxiv.org/PS_cache/hep-th/pdf/0311/0311267v3.pdf