His research deals with
microlocal analysis. He has investigated, inter alia, the Schrödinger equation of an electron in a magnetic field (with a spectrum of the
Hofstadter butterfly),[3] resonances in the semiclassical limit, and
quantum tunneling in the semiclassical limit.
Selected publications
Operators of principal type with interior boundary conditions. Acta mathematica 130, no. 1 (1973): 1–51.
doi:
10.1007/BF02392261
with Anders Melin: "Fourier integral operators with complex-valued phase functions." In Fourier integral operators and partial differential equations, pp. 120–223. Springer, Berlin, Heidelberg, 1975.
doi:
10.1007/BFb0074195
with
Richard Melrose: Singularities of boundary value problems. I, Comm. Pure Appl. Math., vol. 31, 1978, pp. 593–619
doi:
10.1002/cpa.3160310504; Singularities of boundary value problems. II, Comm. Pure Appl. Math., vol. 35, 1982, pp. 129–168
doi:
10.1002/cpa.3160350202
with Helffer: Analyse semi-classique pour l'équation de Harper : (avec application à l'équation de Schrödinger avec champ magnétique), Mémoire SMF,
Nr. 34, 1988,
Nr. 39, 1989,
Nr. 40, 1990 (Parts 1–3)
Asymptotique des résonances pour des obstacles, Séminaire Bourbaki, Nr. 724, 1989/90
His research deals with
microlocal analysis. He has investigated, inter alia, the Schrödinger equation of an electron in a magnetic field (with a spectrum of the
Hofstadter butterfly),[3] resonances in the semiclassical limit, and
quantum tunneling in the semiclassical limit.
Selected publications
Operators of principal type with interior boundary conditions. Acta mathematica 130, no. 1 (1973): 1–51.
doi:
10.1007/BF02392261
with Anders Melin: "Fourier integral operators with complex-valued phase functions." In Fourier integral operators and partial differential equations, pp. 120–223. Springer, Berlin, Heidelberg, 1975.
doi:
10.1007/BFb0074195
with
Richard Melrose: Singularities of boundary value problems. I, Comm. Pure Appl. Math., vol. 31, 1978, pp. 593–619
doi:
10.1002/cpa.3160310504; Singularities of boundary value problems. II, Comm. Pure Appl. Math., vol. 35, 1982, pp. 129–168
doi:
10.1002/cpa.3160350202
with Helffer: Analyse semi-classique pour l'équation de Harper : (avec application à l'équation de Schrödinger avec champ magnétique), Mémoire SMF,
Nr. 34, 1988,
Nr. 39, 1989,
Nr. 40, 1990 (Parts 1–3)
Asymptotique des résonances pour des obstacles, Séminaire Bourbaki, Nr. 724, 1989/90