Quantum social science is an emerging interdisciplinary field that seeks to apply concepts and frameworks from quantum physics to the study of social phenomena. Departing from the traditional mechanistic models that have long influenced social sciences, this field explores how quantum ideas like complementarity and entanglement can offer new insights. While some proponents are motivated by theories suggesting human cognition and interactions are literally based on quantum processes, others primarily leverage the "quantum toolkit" as a mathematical formalism to model social behaviors that classical approaches struggle to explain. This perspective has been particularly influential in psychology and is increasingly affecting areas such as international relations, marking what some refer to as a "quantum turn" in the social sciences.
The intellectual roots of quantum social science trace back to physicists like Niels Bohr, who believed his principle of complementarity extended to biology and psychology, and Erwin Schrödinger, who pondered a "quantum theory of biology." Later, Roger Penrose hypothesized quantum mechanics' role in consciousness, while figures such as Freeman Dyson and David Bohm explored even more direct connections between mind and quantum matter, hinting at a quantum panpsychism. These ideas were popularized by authors like Danah Zohar and Karen Barad. A distinct, more recent approach, known as quantum cognition, emerged in the 1990s. Researchers in this area, including Emmanuel Haven and Andrei Khrennikov, developed mathematical formalisms, arguing that quantum probability theory is superior to classical probability theory for explaining various cognitive effects, often without assuming an underlying physical quantum basis for human cognition. However, some, like political scientist Alexander Wendt, advocate for a literal interpretation, suggesting humans might be "walking wave functions."
At its core, quantum social science fundamentally challenges the classical worldview underpinning social science, particularly questioning tenets like materialism, determinism, and mechanism. Key quantum concepts are reinterpreted for the social domain. For instance, entanglement, where quantum particles are intrinsically linked regardless of distance, is applied to humans who are seen as similarly entangled through shared institutions like language or even physical processes, implying an inherent interconnectedness in society. Another crucial idea is wave function collapse, where a particle's attributes are determined only upon measurement. In the social context, mental states are viewed as potentialities that "collapse" into a judgment or decision. This parallels the "order effect" in social surveys, where the sequence of questions influences responses, much like how a measurement in physics affects the system being studied.
The application of quantum ideas extends across various social and political spheres. Thinkers in politics and diplomacy have long been inspired by quantum concepts; journalist Flora Lewis spoke of the "Quantum Mechanics of Politics" in 1975, and former US Secretary of State George P. Shultz used "quantum diplomacy" to describe managing uncertainty in international relations. James Der Derian further developed quantum diplomacy to understand the complex entanglements of globalization and multiple actors. Beyond diplomacy, quantum principles are being applied in fields like quantum game theory, quantum decision theory, quantum finance, and quantum economics, with some suggesting that a "quantum paradigm" could help design future global economic and financial architectures.
Despite its growing influence, quantum social science faces considerable criticism. The most common objection centers on quantum decoherence, which suggests that quantum effects are generally filtered out at macroscopic levels and therefore cannot significantly impact social systems; physicist Max Tegmark, for example, argues that brains cannot sustain quantum coherence. A related and fundamental controversy revolves around whether quantum concepts should be applied to social systems merely as metaphors or as literal physical descriptions. This debate ties into broader philosophical discussions within science regarding scientific realism, questioning the true nature of the models we use to understand both the physical and social worlds.