706 BOOK R EV[E~A'S

tors, to express the effect o f the interactions between pairs o f elements o f the system; this mus t be coupled with some general procedure for the exhaust ive enumera t ion o f all types o f interacting pairs, - a topological problem conveniently formulated in graphical form. On this basis, it has been possible not only to obtain a qualitative unders tanding, but to a large extent to perform a quant i ta t ive anal- ysis o f such remarkable p h e n o m e n a as superconduct ivi ty and superfluidity. For the reason indicated above, the same methods have also found fruitful applicat ion in the theory o f nuclear structure, where they have led to explanat ion o f the " g a p " in the energy spec t rum o f e v e n nuclei and have made possible a detailed analysis o f the collective excitations o f the nuclear const i tuents . The book under review is mainly concerned with a systematic exposit ion o f the application o f the new me thods to general sys tems of fermions and bosons. It also gives a concise and lucid account of the main features o f superfluidity and a more lengthy discussion o f superconduct ivi ty; there is also a chapter on long- wave electromagnetic radiat ion in dense media. The t rea tment natural ly makes extensive use o f the brilliant contr ibut ions made by the Russian school under Landau ' s leadership, but it does full justice to the no less fundamenta l work o f other physicists, f rom which Landau himself derived much in- spiration. (I know, for instance, from a conversat ion at the Kiev conference, Landau ' s warm ad- mirat ion for the work o f Matsubara . ) The present English t ranslat ion is brought up- to-date by sub- stantial addi t ions supplied by the authors ; hence its designation as a "second edit ion". The print ing and product ion are o f the highest quality.

L.R.

M. TXNKHAM, Superconductiz,ity (Gordon and Breach, New York, 1965. 84 p. paper $2.50, bound $4.50)

P. G. Dt! GrNtqrs, Superconductirity of metals and alloys (Benjamin, New York, 1966. xiv-274 p. Cloth S12.50)

These two monographs are complementa ry in the sense that the reader o f the latter is referred to the former for a more tho rough theoretical discussion o f the foundat ions . Taken together, they pro- vide a competent and up-to-date survey o f the whole subject.

L.R.

M. GOURDIN, Diffusion des dlectrons de haute dnergie (Masson, Paris, 1966. 229 p.)

Bonne monographie , quoique parfois un peu sommaire , et ma lheureusemen t ddparde par un abus , frisant le scandale, d 'am6ricanismes abso lumen t superflus. 11 est regrettable dgalement que la typo- graphie, dans la composi t ion des formules, s 'dcarte des rhgles usuelles, au grand ddpends de la Idgi- bilitd. Les bonnes r~gles, d 'ail leurs tr4s simples, sont dnoncdes dans les r ecommanda t ions de la Com- miss ions des Symboles, Unitds et Nomenc la tu re de I ' IUPAP.

L.R.

K. GOTTFRIED, Quantum mechanics, Vol. i: Fundamen ta l s (Benjamin, New York, 1966. xvii-494 p.)

A textbook in the highest class. The author , with becoming modesty, tells us that he is heavily in Dirac 's and Pauli 's debt. Who is not? Students will henceforth be indebted to him for being int roduced in such a master ly fashion to the great masters ' original concept ions as well as to the latest ref inements they have received. The delight which also seasoned physicists will find in a perusal o f the book is enhanced by a remarkably fine typographical set-up, which does honou r to the enterprising publisher. (The only formal blemish is the use o f aberrant unit symbols , such as ev instead of eV, which ought no longer to be tolerated, especially not in a textbook.)

I should have liked to s top here, but 1 mus t end, regretfully, on a " tu quoque"! . The au thor ' s pil- gr image to Copenhagen has apparent ly not made him qui te firm enough to wi ths tand the subtle pr incetonian heresies, which he quotes approvingly in a footnote on p. 788. Let us hope that this footnote, which spoils an otherwise excellent discussion o f the epistemological quest ions, will be turned into its negat ion in the next edition.

L.R.