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December, 2004 Microlocalization and Stationary Phase
Ricardo García Lopez
Asian J. Math. 8(4): 747-768 (December, 2004).


In [6], G. Laumon defined a set of functors, called by him local Fourier transformations, which allow to analyze the local structure of the l-adic Fourier transform of a constructible l-adic sheaf G on the affine line in terms of the local behaviour of G at infinity and at the points where it is not lisse. These local Fourier transforms play a major role in his cohomological interpretation of the local constants and in his proof of the product formula (see loc. cit. and [5]). In this article, we are concerned with differential systems defined over a field K of characteristic zero. We define a set of functors which allow to prove a stationary phase formula, expressing the formal germ at infinity of the D-module theoretic Fourier transform of a holonomic K[t]h.ti-module M in terms of the formal germs defined by M at its singular points and at infinity. These functors might therefore be regarded as formal analogues of Laumon's local Fourier transformations ... We will use some results from D-module theory for which we refer e.g. to [14], [15]. Our proof of the formal stationary phase formula follows the leitfaden of the one given by C. Sabbah in [15] for modules with regular singularities. I thank C. Sabbah, B. Malgrange, G. Christol and W. Messing for their useful remarks. I thank also G. Lyubeznik and S. Sperber for their invitation to the University of Minnesota, during which part of this work was done.


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Ricardo García Lopez. "Microlocalization and Stationary Phase." Asian J. Math. 8 (4) 747 - 768, December, 2004.


Published: December, 2004
First available in Project Euclid: 13 June 2005

zbMATH: 1100.32005
MathSciNet: MR2127946

Rights: Copyright © 2004 International Press of Boston

Vol.8 • No. 4 • December, 2004
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