E. Fues, Prof. Diffraction Experiments with Matter Waves. Introduction to Quantum Mechanics. Leipzig, Akademische Verlagsgesellschaft, 1935, XV, 351 pp., 186 figs. (Wien-Harms Handbook of Experimental Physics. Supplementary Work. Edited by Wien and Toos, Vol. II).

E. Fues, Prof., Diffraction of Matter Waves. Introduction to Quantum Mechanics.

With each passing year, more and more books and textbooks devoted to quantum mechanics appear. Most of them present approximately the same body of material. A canon has almost already become established: defini-

…things are included in the general textbook; about others the reader can learn only from the specialized literature. There has also become established, to a certain extent, a specific volume for each section. On opening a new book on wave mechanics, there is almost no longer any need to look at the table of contents. It is known in advance how and where the material is arranged.

Nor does Fues’s new book dazzle with novelty or originality. And yet it deserves special attention.

The writer of these lines had occasion three years ago to visit the author and to become acquainted with his style of work. Already then the book was completely ready for press. Yet the author again and again revised and refined the material, seeking out the best methods of exposition. In his work he made use of an enormous card index, into which was entered everything that might be useful for the book: new derivations of known results, new experimental data, separate thoughts and comparisons.

And as a result of such careful treatment there has emerged a work that shines by its finish and completeness. In style it corresponds to its purpose: to be the concluding volume (Ergänzungswerk) in the monograph Wien-Harms Handbuch der Experimentalphysik.

The book falls into two entirely independent parts: the first is devoted to the diffraction of matter waves, the second to wave mechanics.

In the first section it is noticeable that the author was close to the circle of scientists who for many years worked fruitfully in the field of X-ray analysis. The book treats, with exceptional thoroughness, rich and up-to-date experimental material, successfully combined with theoretical investigations. The most recent data are presented in such proportion that reading is not made difficult for the non-specialist.

As for the second section, without claiming novelty or originality, it introduces the reader with unusual vividness and clarity into the circle of the basic problems. Individual derivations may serve as an example of how the difficult sections of mathematical physics ought to be expounded.

Fues’s book is very valuable and deserves translation into Russian.

Yu. Rumer, Moscow