Dear all,
I am struggling to understand why the following integration:
Integrate[t*BesselJ[0,k*r]*(-HeavisideTheta[t-r/a]+HeavisideTheta[t-r/b])/r^2,{r,0,Infinity},Assumptions->{k>=0,a>0,b>0,a>b,t>=0}]
Is not giving the same result as (notice that only the assumption about t>0 or t>=0 has changed):
Integrate[t*BesselJ[0,k*r]*(-HeavisideTheta[t-r/a]+HeavisideTheta[t-r/b])/r^2,{r,0,Infinity},Assumptions->{k>=0,a>0,b>0,a>b,t>0}]
I am expecting the result to be non-zero, because this integration arise from calculating the Fourier transform of a non-zero function in 2D.
Do you have any ideas why the calculation gives two different results?
I am using Mathematica Version 12.2.0.0 on Mac.
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