%0 Journal Article %T Finite Range Decomposition of Gaussian Processes %+ Laboratoire de Physique Mathématique et Théorique (PMT) %A Mitter, Pronob %A Brydges, David %A Guadagni, G. %Z 26 pages, LaTeX, paper in honour of G.Jona-Lasinio.Typos corrected, corrections in section 5 and appendix A %< avec comité de lecture %Z 03-030 %@ 0022-4715 %J Journal of Statistical Physics %I Springer Verlag %V 115 %N 1/2 %P 415-449 %8 2004-04-04 %D 2004 %Z math-ph/0303013 %R 10.1023/B:JOSS.0000019818.81237.66 %K Gaussian processes %K finite range decomposition %K lattice %K renormalization group %K Lévy processes %Z Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO] %Z Sciences of the Universe [physics]/Astrophysics [astro-ph]Journal articles %X Let Delta be the finite difference Laplacian associated to the lattice Z d . For dimension dge3, age0, and L a sufficiently large positive dyadic integer, we prove that the integral kernel of the resolvent G a colone(a–Delta)–1 can be decomposed as an infinite sum of positive semi-definite functions V n of finite range, V n (x–y)=0 for |x–y|geO(L) n . Equivalently, the Gaussian process on the lattice with covariance G a admits a decomposition into independent Gaussian processes with finite range covariances. For a=0, V n has a limiting scaling form $$L^{ - n\left( {d - 2} \right)} \Gamma _{c,*} \left( {\tfrac{{x - y}}{{L^n }}} \right)$$ as nrarrinfin. As a corollary, such decompositions also exist for fractional powers (–Delta)–agr/2, 0 %G English %L hal-00286525 %U https://hal.science/hal-00286525 %~ CNRS %~ UNIV-MONTP2 %~ UNIV-MONTPELLIER %~ UM1-UM2