Law and Policy for the Quantum Age

Law and Policy for the Quantum Age by Chris Jay Hoofnagle and Simson L. Garfinkel. Cambridge University Press, 2022, 577 pp. Also available via open access at https://doi.org/.

This book is required reading for those interested in a deeper understanding of quantum information science (QIS), the field exploring new ways of processing information through quantum mechanics. The co-authors, Chris Hoofnagle and Simson Garfinkel, provide an accessible in-depth review of current QIS innovation to examine what future QIS policy may look like. Hoofnagle is a professor of law at the University of California, Berkeley, and serves on numerous boards of directors, including the board of Palantir Technologies. Garfinkel was formerly a tenured professor at the Naval Postgraduate School and now serves as a senior data scientist at the Department of Homeland Security.

Law and Policy for the Quantum Age stands out because it features all of the leading quantum science fields and presents technological discussions for a broader general audience. It is also comprehensive in its reviews of the leading QIS subdisciplines: quantum sensing, quantum computing, and quantum communication. The book places the dialogue in the context of policy to inspire readers to ask questions relative to what QIS might pose prior to the wider adoption or discovery of novel QIS technologies and the issues that logically flow from these technologies.

Hoofnagle and Garfinkel assert three main theses. First, of the three most widely recognized QIS subdisciplines, quantum sensing—a system using “quantum properties and effects to measure or sense physical things”—poses the greatest potential impact on humanity (31). Second, although quantum computing has gained considerable attention in the mainstream media due to fears that a quantum computer can break most, if not all, existing methods of encryption security, such assertions are exaggerated based on the current state of science. Finally, the authors argue that without government funding, most of the promises offered by QIS will not receive sufficient private funding, leading to a potential “quantum winter” similar to that seen with artificial intelligence (AI).

The authors first argue that “quantum sensing is the most exciting quantum technology and it has the most potential to change our lives in the next decade and beyond” (31). To support their assertion, Hoofnagle and Garfinkel point out that quantum sensing has been in use for many years and has broad applications. The authors cite atomic clocks, GPS, nuclear magnetic resonance, and magnetic resonance imaging as well-known examples of how quantum sensing can trace its development and widespread adoption to the late 1950s.

The authors add that quantum sensing has seen many decades of continued public/private investment and innovation. For example, the Laser Interferometer Gravitational-Wave Observatory (LIGO)—a National Science Foundation, California Institute of Technology, and Massachusetts Institute of Technology partnership—is a prominent recent example of quantum sensing innovation with tangible applications.

Yet one of the authors’ most profound observations is that quantum sensing is “a precursor technology for both computing and communication. . . . [that] will directly or indirectly benefit from investment in other quantum technologies” (461). The authors posit that in order for a quantum computer to become fully developed, refined quantum sensing technology is required to properly measure and manipulate the underlying quantum computational physics for the computer to perform at scale. They contend that “mastery of quantum sensing is necessary for quantum computing, and as that mastery develops, entrepreneurs will likely find many non-computing uses of quantum sensors to be benefit society” (461). Without quantum sensing, quantum computers will, in essence, accelerate the development of quantum sensing technology—compelling support for their argument indeed.

The second overarching thesis Hoofnagle and Garfinkel offer is that though quantum cryptanalysis—the breaking of current widely-adopted public key (RSA) encryption techniques using a quantum computer—is a threat, it is one they “consider to be overhyped” (330). The authors assert two main sub-arguments.

First, the current state-of-the-science is such that universal quantum computers are ostensibly commercially unviable lab experiments. The authors offer pages of evidence that logical qubits—the basic unit of quantum information—number so few and are so unstable, operating for only microseconds, that a computer able to break current public key encryption is not possible for years, potentially even decades. The expert consensus aligns with this conclusion, generally maintaining that quantum computers with sufficient stability to break RSA encryption will not be developed for approximately 10 years.

Second, the authors also cite other works to support their reasoning. For example, a 2016 US Air Force study concluded that “no compelling evidence exists that quantum computers can be usefully applied to computing problems of interest to the Air Force” (245). Further, a 2019 National Academies of Sciences (NAS) study observes that noisy intermediate-scale quantum devices have “ ‘primitive’ gate operations and are plagued by error and decoherence” (241). Though certainly not conclusive, the two studies certainly add considerable weight to the authors’ reasoning.

The case the authors make is very compelling. Yet the above-cited 2019 NAS study itself also states that quantum computation will “require unprecedented control of quantum coherence,” a property upon which quantum sensing also heavily relies.¹ Thus, both technologies suffer from the same afflictions which could arguably cut against the authors’ overarching thesis favoring quantum sensing as the most impactful QIS subdiscipline. Moreover, quantum computing methods such as ion trap, another system modality that leverages both well-developed electromagnetic traps and laser technologies dating back to the 1950s, may in fact result in greater strides in computational design with even more significant national security impacts, consequently making “quantum computing the most exciting form of quantum technology, if a large-scale device can be developed” (461).

Notably, the authors spend three full chapters on quantum computation; the largest single subject in the book. Hoofnagle and Garfinkel do not dismiss quantum computation out of hand. Rather, they reasonably postulate that sensing, based on historical precedent, will likely provide the most near-term successes. Such an assertion stands to reason especially when the degree of historical development and understanding of the component technologies for quantum sensing are considered. Based on the current state-of-the-science, the argument is a reasonable one especially when one considers that a successful quantum computer will require quantum sensing development to function.

Finally, Hoofnagle and Garfinkel argue that without considerable government investment, QIS could suffer a quantum winter similar to that seen with AI in the 1970s and the late 1980s, when both interest and funding in AI waned. The authors argue that classical computation owes much of its successes to high levels of government investment and the same strategy should be repeated if QIS is to succeed.

One potential unique characteristic found in quantum science development, however, is the unprecedented levels of private technological investment. IBM, Google, Amazon, Intel, BaiDu, Alibaba Group, and myriad international start-ups are investing millions—though exact numbers remain unclear—across QIS and are also investing heavily in quantum-compatible software development. This is a phenomenon previously unseen in the early years of classical computers where companies such as IBM owe many of their initial successes to public investment. In the early days of classical computing, such companies did not exist and had to be built, staffed, and led. At present, however, technology companies are far more numerous and, in many cases, possess a public valuation exceeding the gross domestic product of some countries. In essence, what could be happening in tandem in the context of quantum computing is another return on public investment that began decades ago. Consequently, it may be important to consider the impact that the current investment landscape is making on QIS when shaping public policy.

Yet the authors correctly note that since 2018 the US government has passed enabling legislation with the purpose of maintaining US leadership in QIS. For example, the National Quantum Initiative Act and the Quantum Computing Cybersecurity Preparedness Act—passed shortly after this book was published—are notable examples supporting their theses. Moreover, many similar legislative provisions may also be found in current National Defense Authorization Acts (NDAA), a recent example of which was the 2023 James M. Inhofe NDAA, which allocated several million dollars to the Air Force to further develop ion trap computer technology. In short, the authors make a keen point in favor of governmental funding support that appears to have gained considerable momentum with both the Trump and Biden administrations.

This book is a must-read for any civilian or military leader seeking a more comprehensive understanding of QIS and the associated policy implications. The volume is easy to follow, exceedingly well researched, and highly cross-referenced, allowing the reader to move rapidly between various subjects. The publishers and authors have also generously made the e-book open access. At base, quantum information sciences are highly complex. Yet thanks to authors like Hoofnagle and Garfinkel, understanding the subject has just become far less difficult.

R. Aubrey Davis III, Lieutenant Colonel, USAF, Retired, JD