In gratefuZ remerribrance of Marston Morse and John von Neumann This
text formed the basis of an optional course of lectures I gave in German
at the Swiss Federal Institute of Technology (ETH), Zlirich, during the
Wintersemester of 1986-87, to undergraduates whose interests were rather
mixed, and who were supposed, in general, to be acquainted with only the
rudiments of real and complex analysis. The choice of material and the
treatment were linked to that supposition. The idea of publishing this
originated with Dr. Joachim Heinze of Springer- Verlag. I have, in
response, checked the text once more, and added some notes and
references. My warm thanks go to Professor Raghavan Narasimhan and to
Dr. Albert Stadler, for their helpful and careful scrutiny of the
manuscript, which resulted in the removal of some obscurities, and to
Springer-Verlag for their courtesy and cooperation. I have to thank Dr.
Stadler also for his assistance with the diagrams and with the
proof-reading. Zlirich, September, 1987 K. C. Contents Chapter I.
Fourier transforms on L (-oo, oo) 1 §1. Basic properties and examples -.
-----. . --. . -. -. . . -. -. . -. . . . - 1 §2. The L 1-algebra --. .
. . . . . ----. . --. -. . --. . --. . -. . . --. . . . --. -. . 16 §3.
Differentiabili ty properties . . . ---. -. -------. . . . ----. -. . .
-. 18 §4. Localization, Mellin transforms . . . . . . -. -. . . . . . -.
. . . . . -. . -. . 25 §5. Fourier series and Poisson's summation
formula . . . . . . . --. --. . 32 §6. The uniqueness theorem . . . . .
. . -. . . . . . . . . . . -. . . . -. . . . . . . . . . . .