Progress in Organic Chemistry, Vol. II. J. W. Cook, Ed. New York: Academic Press; London: Butterworths, 1953. 212 pp. $7.00

From the Pion Cloud of Tomonaga to the Electron Pairs of Schrieffer: Many Body Wave Functions from Nuclear Physics to Condensed Matter Physics

“…Ogg claimed the observation of persistent electric currents in very dilute solutions of alkali metals in liquid ammonia at temperatures of the order of 180 C. He explained such a phenomenon in terms of trapped electron pairs. Some attempts to reproduce his results, however, gave contradictory results [26,27,28], and apparently the whole thing did not receive any further attention and therefore did not play any role in the development of the microscopic theory of superfluidity, apart from a possible subconscious influence on the Sidney group, as reported by Blatt [10]. It seems that what remained of this research is the Gamow's limerick reported by P. T. Landsberg in his correspondence with Blatt [10] In Ogg's theory it was his intent that the current keep flowing, once sent; so to save himself trouble, he put them in double, and instead of stopping, it went.…”

“…Some attempts to reproduce his results, however, gave contradictory results [26,27,28], and apparently the whole thing did not receive any further attention and therefore did not play any role in the development of the microscopic theory of superfluidity, apart from a possible subconscious influence on the Sidney group, as reported by Blatt [10]. It seems that what remained of this research is the Gamow's limerick reported by P. T. Landsberg in his correspondence with Blatt [10] In Ogg's theory it was his intent that the current keep flowing, once sent; so to save himself trouble, he put them in double, and instead of stopping, it went. The fact that this matter has not been settled up to now, if true, is surprising to us, the more so since Ogg's result is sometimes regarded as the first evidence of strong coupling condensates found in high temperature superconductors.…”

“…Their main objection to Bose-Einstein condensation was that the electron pairs should be large and therefore largely overlapping [11], rather than a gas of tightly bound states, but we did not find a place where the Sidney group advocates that the size of the electron pairs should be small. Instead Blatt [10] on p. 182 reports a sentence by Cooper [34] "...the deep mystery in the theory of superconductivity, the pairing condition" with the comment :" It is unusual to find, five years after the original publication of a theory, an admission by one of the authors that the basic assumption of the theory is a deep mystery to him".…”

“…It seems that the underlying idea was that only small pairs might undergo a Bose-Einstein condensation (BEC). In such a case the quotation of the discussions with Blatt might have been an indirect answer to the strongly polemic comment that Blatt made in his beautiful book on superconductivity [10], stating that BCS did not really understand or at least did not appreciate that their theory actually involves Bose-Einstein condensation of Cooper pairs. We emphasize that even though the quoted paper by Schrieffer follows by 28 years the Blatt book, Schrieffer does not mention it explicitly in his report about their diverging opinions.…”

“…However, as far as we understand, the two-fluid model did not play any role in its construction and the BCS authors claimed not to have used ideas of Bose-Einstein condensation and superfluidity. Actually their relevance to the theory of superconductivity was a matter of debate with the Sidney group of Schafroth and Blatt [10]. In a Physics Today paper published in 1992 [11] Schrieffer mentions the "intense" discussions they had with Blatt before their theory was formulated in connection with the size of the Cooper pairs and the nature of the ground state in superconductors.…”