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On moving fast and breaking things
Craig Piercycpiercy@ans.org
So much of what is happening in federal nuclear policy these days seems driven by a common approach popularized in the technology sector. Silicon Valley calls it “move fast and break things,” a phrase originally associated with Facebook’s early culture under Mark Zuckerberg. The idea emerged in the early 2000s as software companies discovered that rapid iteration, frequent experimentation, and a willingness to tolerate failure could dramatically accelerate innovation. This philosophy helped drive the growth of the social media, smartphones, cloud computing, and digital platforms that now underpin modern economic and social life.
Today, that mindset is also influencing federal nuclear policy. The Trump administration views accelerated nuclear deployment as part of a broader competition with China for technological and AI leadership. In that context, it seems willing to accept greater operational risk in pursuit of strategic advantage and long-term economic and security objectives.
D. C. Hunt, D. C. Coonfield
Nuclear Technology | Volume 12 | Number 3 | November 1971 | Pages 260-268
Technical Paper | Reactor | doi.org/10.13182/NT71-A31005
Articles are hosted by Taylor and Francis Online.
The effects of varying energy group cross-section sets and the space-angle mesh must be understood to evaluate critical parameters computed by the discrete ordinates Sn method. In this paper, these effects are investigated using critical mass calculations on several enriched uranium metal systems. Based on the variation of critical mass with refinement of the space-angle mesh, mesh specification criteria are deduced. The most significant criteria established for these systems is that Sn (n ≥ 16) calculations are required. Next, the literature on fast (En ≥ 3 keV) 235U and 238U neutron cross sections is reviewed and a seven-group cross-section set in this energy range is developed. This fast set is found to reproduce to within 0.5% the measured critical masses of several fast uranium systems. Finally, group cross-section sets in the resolved resonance energy ranges of 235 U and 238U are developed according to several energy self-shielding models. A recommended set is obtained by interpolation between two of these models. This set yields critical masses in good agreement with observed critical masses for several intermediate energy metal critical systems with several 235U enrichments.
