Biology Might Not Be Quantum, but Its Math Is Quantumlike
Scientists have a history of trying — and failing — to link biology and quantum mechanics. The real connection between them may be in the math.
In the late 1920s and 1930s, scientists like Niels Bohr and Pascual Jordan speculated that quantum mechanics might explain biological phenomena. Bohr suggested in a 1929 lecture that quantum mechanics could be crucial for understanding life, while Jordan, a contemporary, developed the field of Quantenbiologie (quantum biology). He argued that life uniquely amplifies quantum indeterminism to macroscopic scales, even linking it to human thought and free will. J.B.S. Haldane, a geneticist, echoed these ideas in 1934. However, Jordan’s association with Nazism in the 1930s damaged the field’s credibility. These early attempts sought to explain life’s puzzling properties using quantum physics, contrasting classical particles (which exist in one state at a time) with quantum particles (which exist in superpositions of multiple states until observed).
Quantum mechanics describes particles as existing in superpositions, meaning they can be in multiple states simultaneously until measured. This is represented mathematically by a wave function, which behaves like a wave with peaks and troughs. When quantum states in superposition have orderly wave properties, they are called coherent and can interfere with each other, either adding up or canceling out. Another quantum phenomenon is entanglement, where particles become linked and share a single wave function. However, quantum states are fragile and easily disrupted by environmental noise, such as heat, a process called decoherence. In a cell’s warm, wet environment, decoherence should occur almost instantly, making long-lived quantum effects unlikely. Even so, small particles like hydrogen atoms can quantum tunnel through energy barriers, though this is a fleeting and unavoidable effect.
In 2007, Graham Fleming and colleagues at the University of California, Berkeley, studied photosynthesis in bacteria and found evidence suggesting that quantum coherence might explain the nearly 100% efficiency of light harvesting. Photosynthetic organisms use light-harvesting complexes—arrays of pigments and proteins—to absorb photons and convert their energy into chemical energy. Fleming’s team observed synchronized beats in excitons (quasiparticles carrying the absorbed energy), which seemed to indicate quantum coherence. Gregory Scholes and others replicated similar results, even at room temperature. However, further research revealed that these beats were caused by molecular bond vibrations, not quantum coherence. The excitement faded as no long-lived quantum effects were confirmed in photosynthesis.
Gregory Scholes, a chemist at Princeton University, initially supported the idea of quantum effects in biology but has since become skeptical. He argues that scaling up quantum phenomena like coherence and entanglement in living systems is impossible due to decoherence. At a 2023 conference, Scholes proposed an alternative: life might not use true quantum effects but instead mimic them mathematically. He suggests that complex networks of classical objects can produce quantumlike behavior, where collective interactions create states that follow the same mathematical rules as quantum systems. Scholes’ work over the past three years has shown that such networks can generate synchronized states resembling qubits, the basic units of quantum information, without being truly quantum.
Quantum states are represented mathematically as vectors in a Hilbert space, a type of coordinate system where states can be added together, mimicking superposition. Scholes demonstrated that complex networks of oscillators—such as coupled pendulums or neurons—can produce emergent states that behave like vectors in Hilbert space. These states can interfere with each other, a key feature of quantum systems. For example, a network designed by Scholes in 2024 produced states mathematically equivalent to a qubit, which can exist in a superposition of two states. Ethan Dickey, a computer scientist at Purdue University, noted that these networks require only reasonable structures to generate such elegant mathematical objects. This suggests that quantumlike behavior can emerge from classical systems without invoking actual quantum physics.
Scholes’ framework proposes that life might achieve quantumlike functionality through evolution rather than true quantum effects. Markus Müller, a physicist at the Institute for Quantum Optics and Quantum Information in Vienna, supports this idea, noting that classical systems can mimic key features of quantum information. Sabre Kais, a quantum chemist at North Carolina State University, called this an exciting new direction. However, not all researchers agree. Ebrahim Karimi, a physicist at the University of Ottawa, argues that using quantum terminology for classical systems is misleading, as interference is a common feature of waves. The debate extends to contentious claims about quantum effects in the brain, where Roger Penrose’s 1989 proposal of quantum consciousness in microtubules remains controversial. Wolf Singer, a neurophysiologist, found that introducing oscillations into neural networks in 2025 improved their efficiency, suggesting that quantumlike modeling might offer useful tools for understanding biological systems.
