This presentation argues that decimal place-value notations have been introduced as material tools of computation and that, until around the 10th century, they were used only as a material notation to compute, and were never shown in illustrations in mathematical writings, let alone used to express numbers. Furthermore, the presentation argues that the same remarks hold true whether we consider the earliest extant evidence for the use of such a numeration system in Chinese, Sanskrit, and Arabic sources. In all these geographical areas, decimal place-value numeration systems were first used as a material notation. These remarks suggest that, as a tool of computation, decimal place-value numeration systems have circulated in the context of a material practice, despite changes in the graphics for the digits, and changes in the materiality of the computation.

If you open a computer today, the biggest chunk of real estate, curiously, is not taken by processors, memories, or circuit boards but by increasingly complex heat sinks. Starting from this observation that all technology today needs extensive heat management systems, this piece theorizes the historical and conceptual dimensions of heat as it relates to computing. Using case studies from the history of computation--including air conditioning of the early mainframe computers running weather simulations (such as ENIAC in IAS in the 1960s) and early Apple machines that refused to run for long (because Steve Jobs, it is said, hated fans)--and history of information--the outsized role of thermodynamics in theorizing information, for example--I argue that computation, in both its hardware and software modalities, must be understood not as a process that produces heat as a byproduct but instead as an emergent phenomenon from the heat production unleashed by industrial capitalism.

Put another way, this talk narrates the story of computation through its thermal history. By tracing the roots of architectural ventilation, air conditioning of mainframes and computer rooms in the 20th century, and thermodynamics' conceptual role in the history of information and software, it outlines how and why fans became, by volume, the biggest part of our computational infrastructures. What epistemological work is done by the centrality of heat in these stories of computation, for example, and how might we reckon with the ubiquitization of thermal technologies of computing in this age of global climate crises?

Between 1980 and 1984, the global computer market was heavily influenced by rising DEFCON levels and industrial espionage, alongside the imposition of restrictions on US computer equipment exports (Leslie, 2018). One notable example was the VAX mini-computer from DEC, which became subject to the COCOM doctrine, restricting its distribution due to its strategic importance. Popular in research communities, the VAX supported the Unix operating system and played a pivotal role in the development of Arpanet and the UUCP networks, both precursors to the modern Internet. Despite restrictions, the VAX was widely imported through workarounds or cloning techniques. This paradox of open-source R&D efforts occurring within a politically closed environment (Russell, 2013; Edwards, 1996) is illustrated by the infamous "Kremvax" joke on Usenet, which falsely claimed the USSR had joined the Internet. The study of the VAX’s role in both Eastern and Western Europe highlights the tension between technological openness and Cold War-era containment policies. These technical and administrative maneuvers, though trivial to the broader public, were crucial for the diffusion and cultural adoption of early data networks at the level of the system administrator working in a computer center eager to become a network node.

Since the 1950s the term "supercomputer" has been used informally to indicate machines felt to have particularly high speed or large data-handling capability. Yet it was only in the 1980s that systematic talk of supercomputers and supercomputing became widespread, when a growing number of supercomputing centers were established in industrialized countries to provide computing power mainly, but not only, for fundamental and applied research. Funding for creating these institutes came from the state. Although arguably at first these machines could be of use only in a few computationally-intensive fields like aerodynamics or the construction of nuclear power plants, sources suggest that there were also scientists from other areas, especially physicists, who promoted the initiative because they regarded increasing computing power as essential for bringing forward their own research. Some of them also had already established contacts with computer manufacturers. In my paper I will discuss and broadly contextualize some of these statements, which in the 1990s developed into a wide-spread rhetoric of a "computer revolution" in the sciences.