Frisch-Peierls memorandum

The Frisch-Peierls memorandum was written by Otto Frisch and Rudolf Peierls while they were both working at Birmingham University, England. The memorandum (a copy of which is held in the Public Record Office at Kew) is dated March 1940.

Related Topics:
Otto Frisch - Rudolf Peierls - Birmingham University

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It is a short piece of work which could be considered to be pivotal in human history.

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The two men were the first to calculate that an atomic bomb would require about 1lb of the isotope Uranium 235.

Related Topics:
Isotope - Uranium 235

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Before it had been assumed that the bomb itself would require many tons of uranium, implying that it was theoretically possible, but not a practical military device. In an earlier letter http://hypertextbook.com/eworld/einstein.shtml to President Franklin D Roosevelt, Einstein had suggested it may need to be delivered by ship but could not be small enough to drop from the air.

Related Topics:
Franklin D Roosevelt - Einstein

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The memo was written in two pithy parts. The 2nd http://www.atomicarchive.com/Docs/Begin/FrischPeierls.shtml was an explanation of the science supporting their conclusions. The first was an elegant and comprehensive outline of the implications of their calculations. It included a proposal that the best defense against such a weapon would be to develop one before Germany did so. In a few short pages these two scientists had anticipated the policies of Deterrence and Mutually Assured Destruction which would shape post war geopolitics.

Related Topics:
Deterrence - Mutually Assured Destruction

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The memorandum helped galvanize both Britain and America down a path which lead to the British MAUD report, the Tube Alloys project, the Manhattan Project and ultimately the bombing of Hiroshima.

Related Topics:
MAUD - Tube Alloys - Manhattan Project - Hiroshima

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What follows is the text of the first, and most prescient, part of the memorandum, taken from Rudolf Peierls book Atomic Histories (1997 AIP).

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