- #1
tirrel
- 50
- 0
Hi...
I hope somebody can help me...
Studying mean field theory in a passage it was necessary to calcolate the inverse of this operator defined on Z^2:
$A(I,K)=-J\sum_e \delta(I,K-e)+1/(\beta)*\delta(I,K)$
where I,K pass all ZxZ and the sum on $e$ is a sum on the for basis vectors e_1,e_2,...,e_4. $\delta(A,B)$ is the usual delta function. $J$ and $\beta$ are constants.
well my book tries to compute $A'(q,p)$ as the discrete time Fourier transform of $A(I,K)$... then finds a certain function $g$ which respects this equation $A'(q,p)*g(q,p)=\delta(q-p)$ and anti-transforms it, pretending thus to find an integral representation of the inverse matrix...
unluckily I don't see why this passage is true... does anybody can help me?
I hope somebody can help me...
Studying mean field theory in a passage it was necessary to calcolate the inverse of this operator defined on Z^2:
$A(I,K)=-J\sum_e \delta(I,K-e)+1/(\beta)*\delta(I,K)$
where I,K pass all ZxZ and the sum on $e$ is a sum on the for basis vectors e_1,e_2,...,e_4. $\delta(A,B)$ is the usual delta function. $J$ and $\beta$ are constants.
well my book tries to compute $A'(q,p)$ as the discrete time Fourier transform of $A(I,K)$... then finds a certain function $g$ which respects this equation $A'(q,p)*g(q,p)=\delta(q-p)$ and anti-transforms it, pretending thus to find an integral representation of the inverse matrix...
unluckily I don't see why this passage is true... does anybody can help me?