Papers by Harper Kerkhoff
Archive for History of Exact Sciences, Aug 18, 2020
We report on an unpublished and previously unknown manuscript of John von Neumann and contextuali... more We report on an unpublished and previously unknown manuscript of John von Neumann and contextualize it within the development of the theory of shock waves and detonations during the nineteenth and twentieth centuries. Von Neumann studies bombs comprising a primary explosive charge along with explosive booster material. His goal is to calculate the minimal amount of booster needed to create a sustainable detonation, presumably because booster material is often more expensive and more volatile. In service of this goal, he formulates and analyzes a partial differential equation-based model describing a moving shock wave at the interface of detonated and undetonated material. We provide a complete transcription of von Neumann's work and give our own accompanying explanations and analyses, including the correction of two small errors in his calculations. Today, detonations are typically modeled using a combination of experimental results and numerical simulations particular to the shape and materials of the explosive, as the complex three dimensional dynamics of detonations are analytically intractable. Although von Neumann's manuscript will not revolutionize our modern understanding of detonations, the document is a valuable historical record of the state of hydrodynamics research during and after World War II.
arXiv (Cornell University), Apr 7, 2020
We report on an unpublished and previously unknown manuscript of John von Neumann and contextuali... more We report on an unpublished and previously unknown manuscript of John von Neumann and contextualize it within the development of the theory of shock waves and detonations during the nineteenth and twentieth centuries. Von Neumann studies bombs comprising a primary explosive charge along with explosive booster material. His goal is to calculate the minimal amount of booster needed to create a sustainable detonation, presumably because booster material is often more expensive and more volatile. In service of this goal, he formulates and analyzes a partial differential equation based model describing a moving shock wave at the interface of detonated and undetonated material. We provide a complete transcription of von Neumann's work and give our own accompanying explanations and analyses, including the correction of two small errors in his calculations. Today, detonations are typically modeled using a combination of experimental results and numerical simulations particular to the shape and materials of the explosive, as the complex three dimensional dynamics of detonations are analytically intractable. Although von Neumann's manuscript will not revolutionize our modern understanding of detonations, the document is a valuable historical record of the state of hydrodynamics research during and after World War II.
Archive for History of Exact Sciences, 2020
We report on an unpublished and previously unknown manuscript of John von Neumann and contextuali... more We report on an unpublished and previously unknown manuscript of John von Neumann and contextualize it within the development of the theory of shock waves and detonations during the nineteenth and twentieth centuries. Von Neumann studies bombs comprising a primary explosive charge along with explosive booster material. His goal is to calculate the minimal amount of booster needed to create a sustainable detonation, presumably because booster material is often more expensive and more volatile. In service of this goal, he formulates and analyzes a partial differential equation-based model describing a moving shock wave at the interface of detonated and undetonated material. We provide a complete transcription of von Neumann’s work and give our own accompanying explanations and analyses, including the correction of two small errors in his calculations. Today, detonations are typically modeled using a combination of experimental results and numerical simulations particular to the shape ...
Motivated by the well-established benefits to society of artistic creation and of demographic div... more Motivated by the well-established benefits to society of artistic creation and of demographic diversity, we investigate the gender and racial/ethnic composition of influential contributors to four creative domains. Women make up 51% of the U.S. population but are underrepresented at influential levels of contemporary art (28%), high fashion (45%), box office film (27%), and popular music (17%). Marginalized racial/ethnic groups make up 39% of the U.S. population yet comprise approximately half that figure in contemporary art (22%), high fashion (22%), and box office film (19%). Black musical artists have higher representation (48%), though higher representation does not equate with equity and inclusion. As for intersecting identities, white men are overrepresented in all four domains by factors ranging from 1.4 to 2 as compared to the U.S. population, and most other gender-racial/ethnic groups are further minoritized. Our study is the first comprehensive, comparative, empirical look...
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Papers by Harper Kerkhoff