Books by Roberto Lalli
This monograph presents a new perspective on the history of general relativity. It outlines the a... more This monograph presents a new perspective on the history of general relativity. It outlines the attempts to establish an institutional framework for the promotion of the field during the Cold War. Readers will learn the difficulties that key figures experienced and overcame during this period of global conflict.
The author analyzes the subtle interconnections between scientific and political factors. He shows how politics shaped the evolution of general relativity, even though it is a field with no military applications. He also details how different scientists held quite different views about what “political” meant in their efforts to pursue international cooperation.
The narrative examines the specific epistemic features of general relativity that helped create the first official, international scientific society. It answers: Why did relativity bring about this unique result? Was it simply the product of specific actions of particular actors having an illuminated view of international relations in the specific context of the Cold War? Or, was there something in the nature of the field that inspired the actors to pioneer new ways of international cooperation?
The book will be of interest to historians of modern science, historians of international relations, and historians of institutions. It will also appeal to physicists and interested general readers.
Papers by Roberto Lalli
The recent discovery of gravitational waves is often seen as the confirmation of a prediction Ein... more The recent discovery of gravitational waves is often seen as the confirmation of a prediction Einstein made one century ago.
We argue instead that only after conceptual advances in general relativity between the mid-1950s and the early 1960s could
such a prediction be made on the basis of unambiguous notions shared by a community of specialists. The conceptual transformation
and the reorganization of knowledge related to general relativity that characterized this post-Second World War period
can be used to properly understand the hitherto vaguely defined ‘renaissance of general relativity’. During its first phase, theoreticians
took a conservative turn by refocusing on general relativity, after previously having worked on other research agendas
mostly targeted at substituting general relativity with a superior theory. This turn was followed by a second phase that was
characterized by a plurality of approaches to general relativity, which had in common the fact that they were able to develop
intrinsically (generally) relativistic concepts, in particular radiation, rather than using other theories as an interpretative crutch.
In the 1930s the mathematical physicist Howard P. Robertson was the main referee of the
journal P... more In the 1930s the mathematical physicist Howard P. Robertson was the main referee of the
journal Physical Review for papers concerning general relativity and related subjects. The
rich correspondence between Robertson and the editors of the journal enables a historical
investigation of the refereeing process of Physical Review at the time that it was
becoming one of the most influential physics periodicals in the world. By focusing on this
case study, the paper investigates two complementary aspects of the evolution of the
refereeing process: first, the historical evolution of the refereeing practices in connection
with broader contextual changes, and second, the attempts to define the activity of the
referee, including the epistemic virtues required and the journal’s functions according to
the participants’ categories. By exploring the tension between Robertson’s idealized
picture about how the referee should behave and the desire to promote his intellectual
agenda, I show that the evaluation criteria that Robertson employed were contextually
dependent and I argue that, in the 1930s, through his reports the referee had an enormous
power in defining what direction future research should take.
European Physical Journal H, 2017
Einstein’s 1915 theory of gravitation, also known as General Relativity, is now considered one of... more Einstein’s 1915 theory of gravitation, also known as General Relativity, is now considered one of the pillars of modern physics. It contributes to our understanding of cosmology and of fundamental interactions between particles. But that was not always the case. Between the mid-1920s and the mid-1950s, General Relativity underwent a period of stagnation, during which the theory was mostly considered as a stepping-stone for a superior theory. In a special issue of EPJ H just published, historians of science and physicists actively working on General Relativity and closely related fields share their views on the process, during the post-World War II era, in particular, which saw the “Renaissance” of General Relativity, following progressive transformation of the theory into a bona fidae physics theory.
In this special issue, new insights into the historical process leading to this renaissance point to the extension of the foundation of the original theory, ultimately leading to a global transformation in its character. Contributions from several experts reveals that the theory of 1915 was insufficient to reach firm conclusions without being complemented by intuitions drawn from the resources of pre-relativistic physics. Or, in the case of cosmology, the theory needed to be complemented by philosophical considerations that were hardly generalizable to help solve more mundane problems.
As physicist Pascual Jordan puts it, there was a “mismatch between the simplicity of the physical and epistemological foundations and the annoying complexity of the corresponding thicket of formulae.”
A number of contributions in this special issue also explain how the theory underwent a period of successive controversies, leading by the 1960s, to the renaissance of the theory. Subsequently, it became in the 1970s, an important, empirically well-tested branch of theoretical physics related to the new, successful sub-discipline of relativistic astrophysics.
Isis; an international review devoted to the history of science and its cultural influences, 2015
The history of the theory of general relativity presents unique features. After its discovery, th... more The history of the theory of general relativity presents unique features. After its discovery, the theory was immediately confirmed and rapidly changed established notions of space and time. The further implications of general relativity, however, remained largely unexplored until the mid 1950s, when it came into focus as a physical theory and gradually returned to the mainstream of physics. This essay presents a historiographical framework for assessing the history of general relativity by taking into account in an integrated narrative intellectual developments, epistemological problems, and technological advances; the characteristics of post-World War II and Cold War science; and newly emerging institutional settings. It argues that such a framework can help us understand this renaissance of general relativity as a result of two main factors: the recognition of the untapped potential of general relativity and an explicit effort at community building, which allowed this formerly di...
Die Zukunft der Wissensspeicher. Forschen, Sammeln und Vermitteln im 21. Jahrhundert, ed. by J. Mittelstraß und U. Rüdiger, 2016
Annalen der Physik, 2016
After an initial burst of excitement about its extraordinary implications for our concept of spac... more After an initial burst of excitement about its extraordinary implications for our concept of space and time, the theory of general relativity underwent a thirty-year period of stagnation, during which only a few specialists worked on it, achieving little progress. In the aftermath of World War II, however, general relativity gradually re-entered the mainstream of physics, attracting an increasing number of practitioners and becoming the basis for the current standard theory of gravitation and cosmology-a process Clifford Will baptized the Renaissance of General Relativity. The recent detection of gravitational radiation by the LIGO experiment can be seen as one of the most outstanding achievements in this long-lasting historical process. In the paper, we present a new multifaceted historical perspective on the causes and characteristics of the Renaissance of General Relativity, focusing in particular on the case of gravitational radiation in order to illustrate this complex and far-reaching process.
Annalen der Physik, 2014
The paper explores the process that led to the establishment of the journal Reviews of Modern Phy... more The paper explores the process that led to the establishment of the journal Reviews of Modern Physics, which was to become one of the most prestigious physics periodicals from the 1930s onward. When the journal was proposed in 1928, it represented a strong novelty. It was the first scientific periodical to be explicitly and entirely devoted to the publication of long and comprehensive review articles in physics. The novelty of the proposal entailed a series of questions, anxieties, concerns and disagreements between the physicists called to give their opinions on the planned publication. It is argued that the final format of the journal was the result of the negotiation between very different views about the role of review articles in the activities of the American Physical Society. This ‘genetic’ process made the journal elastic enough to be flexible to the changing needs of American physics community during the following years.
Historical Studies of Natural Sciences 43 (2013): 41-104, 2013
Between 1937 and 1953 the industrial physicist Herbert E. Ives pursued a research project with th... more Between 1937 and 1953 the industrial physicist Herbert E. Ives pursued a research project with the aim of challenging the acceptance of relativity theories, becoming the most important American opponent of Einstein of the period. During his anti-relativistic activity Ives also performed the famous Ives-Stilwell experiment. Usually interpreted as the first direct confirmation of the time dilation formula of special relativity theory, Ives regarded the experiment as a proof of what he called the Larmor-Lorentz theory. Ives’s heterodox views about relativity were mainly ignored by the scientific community during his lifetime. After his death, however, his criticisms of what the majority of physicists took for granted helped to spark the late 1950s philosophical discussions around the conventional stipulation of distant simultaneity in special relativity theory.
Ives’s anti-relativistic beliefs and actions allow an analysis of the heterodox efforts of an accredited member of the scientific community and the subsequent process of his professional marginalization in a specific historical and scientific context. This paper has three aims: first, to uncover the epistemic roots of Ives’s opposition to relativity; second, to analyze Ives’s rhetorical strategies and the reasons why he failed to persuade his peers; and, lastly, to draw distinctions between the public network of allies Ives built in scientific publications and the hidden network of allies present in his correspondence. It will become clear that the hardening of Ives’s tone against relativity and Einstein depended on the progressive marginalization and loss of recognized socio-professional identity due to Ives’s unorthodox ideas about relativity. Ives’s case is illuminating for several historical, philosophical and sociological perspectives concerning the complex mechanisms through which the margins interact with the mainstream of science, both in the production of certified knowledge and in the contextually contingent re-definition and re-configuration of the boundaries of acceptable scientific discourse.
Physics, Astronomy and Engineering: A Bridge between Conceptual Frameworks, Society and Technologies edited by R. Pisano, D. Capecchi
Karl K. Darrow was a central actor in the reception of quantum theory in the Bell Telephone Labor... more Karl K. Darrow was a central actor in the reception of quantum theory in the Bell Telephone Laboratories. He was the first industrial physicist to dedicate his entire working time to the dissemination of novel concepts and theoretical tools by means of long review papers. The present paper analyzes the evolution of Darrow’s narratives of quantum theory and shows that Darrow’s
reviews aimed at substantiating the view that physics was an evolutionary process.
The paper argues that this view was connected to Darrow’s peculiar activity at the Bell Labs as well as to the contemporaneous attempts of leading American scientists to build an ideology of national science.
Annals of Science, 69 (2012): 153-214, 2012
This paper analyses documents from several US archives in order to examine the controversy that r... more This paper analyses documents from several US archives in order to examine the controversy that raged within the US scientific community over Dayton C. Miller’s ether-drift experiments. In 1925, Miller announced that his repetitions of the famous Michelson-Morley experiment had shown a slight but positive result: an ether-drift of about 10 kilometres per second. Miller’s discovery triggered a long debate in the US scientific community about the validity of Einstein’s relativity theories. Between 1926 and 1930 some researchers repeated the Michelson-Morley
experiment, but no one found the same effect as Miller had. The inability to confirm Miller’s result, paired with the fact that no other ether theory existed that could compete with special relativity theory, made his result an enigmatic one. It thus remained of little interest to the scientific community until 1954, when Robert
S. Shankland and three colleagues reanalysed the data and proposed that Miller’s periodic fringe shift could be attributed to temperature effects. Whereas most of the scientific community readily accepted this explanation as the conclusion of the matter, some contemporary anti-relativists have contested Shankland’s
methodology up to now. The historical accounts of Miller’s experiments provide contradictory reports of the reaction of the US scientific community and do not analyse the mechanisms of the controversy. I will address this shortcoming with an examination of private correspondence of several actors involved in these experiments between 1921 and 1955. A complex interconnection of epistemic elements, sociological factors, and personal interests played a fundamental role in the closure of this experimental controversy in the early 1930s, as well as in the reception of Shankland’s reanalysis in the 1950s.
Physics, Astronomy and Engineering. Critical Problems in the History of Science. International 32nd Congress for The SISFA–Italian Society of Historians of Physics and Astronomy, edited by R. Pisano, D. Capecchi and A. Lukešová , 2013
In 1938, the American industrial physicist Herbert E. Ives performed the Ives-Stilwell experiment... more In 1938, the American industrial physicist Herbert E. Ives performed the Ives-Stilwell experiment, named after him and his assistant G. R. Stilwell. While physics textbooks describe the experiment as a confirmation of special relativity theory (SRT), Ives regarded the result of the experiment as a proof of the Larmor-Lorentz hypothesis of the contraction of the time-pulse of an atomic clock in motion through the ether. The aim of this communication is to provide a historical analysis of Ives's motivations to perform the experiment as well as of his theoretical presuppositions concerning the relationship between ether theories and relativity.
![Research paper thumbnail of Effetto Sagnac (1913): Storia di un mancato dibattito nella Francia degli anni ’20” [The Sagnac Effect (1913): History of a Missing Debate in France during the 1920s]](https://attachments.academia-assets.com/32769811/thumbnails/1.jpg)
Quaderni di Storia della Fisica, 17 (2011): 47-81
In questo lavoro si approfondisce la storia della scoperta e delle prime interpretazioni dell'eff... more In questo lavoro si approfondisce la storia della scoperta e delle prime interpretazioni dell'effetto Sagnac, portato alla luce nel 1913 a Parigi dal fisico omonimo. L'effetto Sagnacè spesso utilizzato da alcuni fisici antirelativisti come anomalia della teoria della relatività ristretta, in particolare come confutazione sperimentale del principio dell'invarianza della velocità della luce in ogni sistema inerziale. A causa del dibattito teorico e delle applicazioni dell'effetto nella navigazione aerospaziale, esistono alcune rivisitazioni storiche, ma nessuna di queste si sofferma sugli accadimenti immediatamente prossimi a tale scoperta. Siè deciso di colmare questa lacuna approfondendo la vita e le idee dell'artefice dell'esperimento, il suo rapporto con la comunità scientifica francese e le reazioni di questa alle proclamazioni antirelativiste dello stesso Sagnac.
Styles of Thinking in Science and Technology: Proceedings of the III International Congress of the European Society of the History of Science, edited by H. Hunger, F. Seebacher, and G. Holzer, (Wien, Austrian Academy of Science Press, 2010), pp. 963-71, 2010
The Circulation of Science and Technology: Proceedings of the 4th International Conference of the ESHS, Barcelona, 18-20 November 2010, edited by A. Roca-Rosell, 2012
In Atti del XXX Congresso della SISFA, edited by R. Mantovani (Urbino: Argalia Editore, 2012), pp. 203-12 , 2012
Intorno a Galileo: La Storia della Fisica e il Punto di Svolta Galileiano. Vol. 9 of Quaderni del CE.R.CO., edited by E. Giannetto, G. Giannini, and M. Toscano , 2011
Conference Presentations by Roberto Lalli
Historians of physics have paid great attention to the history of the Michelson-Morley experiment... more Historians of physics have paid great attention to the history of the Michelson-Morley experiment and its repetitions in order to elucidate their role in the genesis and widespread acceptance of the theory of special relativity (SRT). This narrow focus of investigation has established a historiographical tradition that looks at the ether-drift experiments from a theory-driven perspective interested only in their theoretical interpretations and in the conceptual controversies they sparked. In his examination of Michelson’s research activities, historian of science Richard Staley has held a different perspective by exploring the broad network of interests and intellectual commitments that shaped Michelson’s early work on the ether-drift experiments. Staley maintains that in order to understand Michelson’s contributions it is essential to take into consideration historical issues specifically belonging to the experimental life, such as the relationships with instrument makers and the developments of measuring techniques. In the present paper, I develop Staley’s approach by focusing on the set of cultural and sociological stimuli underlying the work of the experimenters who either performed Michelson-Morley-type experiments or conceived novel 2nd order ether-drift experiments from 1887 up to the early 1960s. I will show that in the experimenters’ view of the ether-drift experiments, theoretical commitments were inextricably connected with different motivations related to the fragile equilibrium between innovations and traditions of experimental practice and instrument making. I argue that the analysis of such interconnections is indispensable in writing a full-fledged history of the ether-drift experiments during the 20th century. As a first step in this direction, a survey of the ether-drift experiments and their relationships with both theoretical assumptions and changing experimental practice is exposed.
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Books by Roberto Lalli
The author analyzes the subtle interconnections between scientific and political factors. He shows how politics shaped the evolution of general relativity, even though it is a field with no military applications. He also details how different scientists held quite different views about what “political” meant in their efforts to pursue international cooperation.
The narrative examines the specific epistemic features of general relativity that helped create the first official, international scientific society. It answers: Why did relativity bring about this unique result? Was it simply the product of specific actions of particular actors having an illuminated view of international relations in the specific context of the Cold War? Or, was there something in the nature of the field that inspired the actors to pioneer new ways of international cooperation?
The book will be of interest to historians of modern science, historians of international relations, and historians of institutions. It will also appeal to physicists and interested general readers.
Papers by Roberto Lalli
We argue instead that only after conceptual advances in general relativity between the mid-1950s and the early 1960s could
such a prediction be made on the basis of unambiguous notions shared by a community of specialists. The conceptual transformation
and the reorganization of knowledge related to general relativity that characterized this post-Second World War period
can be used to properly understand the hitherto vaguely defined ‘renaissance of general relativity’. During its first phase, theoreticians
took a conservative turn by refocusing on general relativity, after previously having worked on other research agendas
mostly targeted at substituting general relativity with a superior theory. This turn was followed by a second phase that was
characterized by a plurality of approaches to general relativity, which had in common the fact that they were able to develop
intrinsically (generally) relativistic concepts, in particular radiation, rather than using other theories as an interpretative crutch.
journal Physical Review for papers concerning general relativity and related subjects. The
rich correspondence between Robertson and the editors of the journal enables a historical
investigation of the refereeing process of Physical Review at the time that it was
becoming one of the most influential physics periodicals in the world. By focusing on this
case study, the paper investigates two complementary aspects of the evolution of the
refereeing process: first, the historical evolution of the refereeing practices in connection
with broader contextual changes, and second, the attempts to define the activity of the
referee, including the epistemic virtues required and the journal’s functions according to
the participants’ categories. By exploring the tension between Robertson’s idealized
picture about how the referee should behave and the desire to promote his intellectual
agenda, I show that the evaluation criteria that Robertson employed were contextually
dependent and I argue that, in the 1930s, through his reports the referee had an enormous
power in defining what direction future research should take.
In this special issue, new insights into the historical process leading to this renaissance point to the extension of the foundation of the original theory, ultimately leading to a global transformation in its character. Contributions from several experts reveals that the theory of 1915 was insufficient to reach firm conclusions without being complemented by intuitions drawn from the resources of pre-relativistic physics. Or, in the case of cosmology, the theory needed to be complemented by philosophical considerations that were hardly generalizable to help solve more mundane problems.
As physicist Pascual Jordan puts it, there was a “mismatch between the simplicity of the physical and epistemological foundations and the annoying complexity of the corresponding thicket of formulae.”
A number of contributions in this special issue also explain how the theory underwent a period of successive controversies, leading by the 1960s, to the renaissance of the theory. Subsequently, it became in the 1970s, an important, empirically well-tested branch of theoretical physics related to the new, successful sub-discipline of relativistic astrophysics.
Ives’s anti-relativistic beliefs and actions allow an analysis of the heterodox efforts of an accredited member of the scientific community and the subsequent process of his professional marginalization in a specific historical and scientific context. This paper has three aims: first, to uncover the epistemic roots of Ives’s opposition to relativity; second, to analyze Ives’s rhetorical strategies and the reasons why he failed to persuade his peers; and, lastly, to draw distinctions between the public network of allies Ives built in scientific publications and the hidden network of allies present in his correspondence. It will become clear that the hardening of Ives’s tone against relativity and Einstein depended on the progressive marginalization and loss of recognized socio-professional identity due to Ives’s unorthodox ideas about relativity. Ives’s case is illuminating for several historical, philosophical and sociological perspectives concerning the complex mechanisms through which the margins interact with the mainstream of science, both in the production of certified knowledge and in the contextually contingent re-definition and re-configuration of the boundaries of acceptable scientific discourse.
reviews aimed at substantiating the view that physics was an evolutionary process.
The paper argues that this view was connected to Darrow’s peculiar activity at the Bell Labs as well as to the contemporaneous attempts of leading American scientists to build an ideology of national science.
experiment, but no one found the same effect as Miller had. The inability to confirm Miller’s result, paired with the fact that no other ether theory existed that could compete with special relativity theory, made his result an enigmatic one. It thus remained of little interest to the scientific community until 1954, when Robert
S. Shankland and three colleagues reanalysed the data and proposed that Miller’s periodic fringe shift could be attributed to temperature effects. Whereas most of the scientific community readily accepted this explanation as the conclusion of the matter, some contemporary anti-relativists have contested Shankland’s
methodology up to now. The historical accounts of Miller’s experiments provide contradictory reports of the reaction of the US scientific community and do not analyse the mechanisms of the controversy. I will address this shortcoming with an examination of private correspondence of several actors involved in these experiments between 1921 and 1955. A complex interconnection of epistemic elements, sociological factors, and personal interests played a fundamental role in the closure of this experimental controversy in the early 1930s, as well as in the reception of Shankland’s reanalysis in the 1950s.
Conference Presentations by Roberto Lalli
The author analyzes the subtle interconnections between scientific and political factors. He shows how politics shaped the evolution of general relativity, even though it is a field with no military applications. He also details how different scientists held quite different views about what “political” meant in their efforts to pursue international cooperation.
The narrative examines the specific epistemic features of general relativity that helped create the first official, international scientific society. It answers: Why did relativity bring about this unique result? Was it simply the product of specific actions of particular actors having an illuminated view of international relations in the specific context of the Cold War? Or, was there something in the nature of the field that inspired the actors to pioneer new ways of international cooperation?
The book will be of interest to historians of modern science, historians of international relations, and historians of institutions. It will also appeal to physicists and interested general readers.
We argue instead that only after conceptual advances in general relativity between the mid-1950s and the early 1960s could
such a prediction be made on the basis of unambiguous notions shared by a community of specialists. The conceptual transformation
and the reorganization of knowledge related to general relativity that characterized this post-Second World War period
can be used to properly understand the hitherto vaguely defined ‘renaissance of general relativity’. During its first phase, theoreticians
took a conservative turn by refocusing on general relativity, after previously having worked on other research agendas
mostly targeted at substituting general relativity with a superior theory. This turn was followed by a second phase that was
characterized by a plurality of approaches to general relativity, which had in common the fact that they were able to develop
intrinsically (generally) relativistic concepts, in particular radiation, rather than using other theories as an interpretative crutch.
journal Physical Review for papers concerning general relativity and related subjects. The
rich correspondence between Robertson and the editors of the journal enables a historical
investigation of the refereeing process of Physical Review at the time that it was
becoming one of the most influential physics periodicals in the world. By focusing on this
case study, the paper investigates two complementary aspects of the evolution of the
refereeing process: first, the historical evolution of the refereeing practices in connection
with broader contextual changes, and second, the attempts to define the activity of the
referee, including the epistemic virtues required and the journal’s functions according to
the participants’ categories. By exploring the tension between Robertson’s idealized
picture about how the referee should behave and the desire to promote his intellectual
agenda, I show that the evaluation criteria that Robertson employed were contextually
dependent and I argue that, in the 1930s, through his reports the referee had an enormous
power in defining what direction future research should take.
In this special issue, new insights into the historical process leading to this renaissance point to the extension of the foundation of the original theory, ultimately leading to a global transformation in its character. Contributions from several experts reveals that the theory of 1915 was insufficient to reach firm conclusions without being complemented by intuitions drawn from the resources of pre-relativistic physics. Or, in the case of cosmology, the theory needed to be complemented by philosophical considerations that were hardly generalizable to help solve more mundane problems.
As physicist Pascual Jordan puts it, there was a “mismatch between the simplicity of the physical and epistemological foundations and the annoying complexity of the corresponding thicket of formulae.”
A number of contributions in this special issue also explain how the theory underwent a period of successive controversies, leading by the 1960s, to the renaissance of the theory. Subsequently, it became in the 1970s, an important, empirically well-tested branch of theoretical physics related to the new, successful sub-discipline of relativistic astrophysics.
Ives’s anti-relativistic beliefs and actions allow an analysis of the heterodox efforts of an accredited member of the scientific community and the subsequent process of his professional marginalization in a specific historical and scientific context. This paper has three aims: first, to uncover the epistemic roots of Ives’s opposition to relativity; second, to analyze Ives’s rhetorical strategies and the reasons why he failed to persuade his peers; and, lastly, to draw distinctions between the public network of allies Ives built in scientific publications and the hidden network of allies present in his correspondence. It will become clear that the hardening of Ives’s tone against relativity and Einstein depended on the progressive marginalization and loss of recognized socio-professional identity due to Ives’s unorthodox ideas about relativity. Ives’s case is illuminating for several historical, philosophical and sociological perspectives concerning the complex mechanisms through which the margins interact with the mainstream of science, both in the production of certified knowledge and in the contextually contingent re-definition and re-configuration of the boundaries of acceptable scientific discourse.
reviews aimed at substantiating the view that physics was an evolutionary process.
The paper argues that this view was connected to Darrow’s peculiar activity at the Bell Labs as well as to the contemporaneous attempts of leading American scientists to build an ideology of national science.
experiment, but no one found the same effect as Miller had. The inability to confirm Miller’s result, paired with the fact that no other ether theory existed that could compete with special relativity theory, made his result an enigmatic one. It thus remained of little interest to the scientific community until 1954, when Robert
S. Shankland and three colleagues reanalysed the data and proposed that Miller’s periodic fringe shift could be attributed to temperature effects. Whereas most of the scientific community readily accepted this explanation as the conclusion of the matter, some contemporary anti-relativists have contested Shankland’s
methodology up to now. The historical accounts of Miller’s experiments provide contradictory reports of the reaction of the US scientific community and do not analyse the mechanisms of the controversy. I will address this shortcoming with an examination of private correspondence of several actors involved in these experiments between 1921 and 1955. A complex interconnection of epistemic elements, sociological factors, and personal interests played a fundamental role in the closure of this experimental controversy in the early 1930s, as well as in the reception of Shankland’s reanalysis in the 1950s.