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The B2FH paper, named after the initials of the authors of the paper, Margaret Burbidge, Geoffrey Burbidge, William Fowler, and Fred Hoyle, is a landmark paper of stellar physics published in ''Reviews of Modern Physics'' in 1957.〔 〕 The formal title of the paper is ''Synthesis of the Elements in Stars'', but the article is generally referred to only as "B2FH". The paper comprehensively outlined and analyzed several key processes that might be responsible for the synthesis of elements in nature and their relative abundance, and it is credited with originating what is now the theory of stellar nucleosynthesis. ==Physics in 1957== At the time of the publication of the B2FH paper, George Gamow advocated a theory of the universe according to which virtually all elements, or atomic nuclei, were synthesized during the big bang. The implications of Gamow's nucleosynthesis theory (not to be confused with present-day nucleosynthesis theory) is that nuclear abundances in the universe are largely static. Together, Hans Bethe and Charles L. Critchfield had derived the Proton proton chain (pp-chain) in 1938,〔 〕 and Carl von Weizsäcker〔 〕 and Hans Bethe〔 〕 and independently, had derived the CNO cycle in 1938 and 1939, respectively, to show that the conversion of hydrogen to helium by nuclear fusion could account for stellar energy production. Thus, it was known by Gamow and others in 1957 that the abundances of hydrogen and helium were not perfectly static. At the time, stellar fusion theories did not show how to create any elements heavier than helium, however, and Gamow advocated the theory that all elements were residual from the big bang, allowing for slight changes in the ratios of hydrogen and helium. The four collaborators who authored B2FH gave a different account for the origin of heavy elements, however, suggesting that all atomic nuclei heavier than lithium up to uranium must have been synthesized in stars rather than during the big bang. Both theories agree that some light nuclei (hydrogen, and some helium and lithium) were not created in stars, and this led to the now-accepted theory of big bang nucleosynthesis. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「B2FH paper」の詳細全文を読む スポンサード リンク
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