Researchers find quantum-like signals in cells

Cells are full of wires. Not metal wires — protein wires. And a new paper argues those wires may let living cells move information around in a way that looks a lot more like quantum optics than ordinary biochemistry. That matters because most models of cellular signaling still assume the important action happens through slower chemical cascades. Philip Kurian at Howard University is pushing a much stranger idea: some eukaryotic cells may exploit collective light-matter effects inside their cytoskeleton, at room temperature, to process signals incredibly fast. ### What actually changed? The new piece of news is a March 28, 2025 Science Advances paper by Kurian called *Computational capacity of life in relation to the universe*. The paper does not show a cell doing a quantum algorithm in a dish. Basically, it takes an earlier experimental result from Kurian’s group — evidence for single-photon superradiance in cytoskeletal protein fibers at thermal equilibrium — and uses that as the physical basis for a new estimate of how much computation life could, in principle, perform. (science.org) ### What is the cytoskeleton here? The cytoskeleton is the protein scaffold inside cells — microtubules, actin filaments, and related structures that give cells shape and help move cargo around. Kurian’s argument treats some of these filaments not just as mechanical supports but as optical networks built from tryptophan molecules, which can absorb and emit ultraviolet light. That is the big conceptual jump. The claim is that these protein architectures may support coordinated excitations, not just random local chemistry. (science.org) ### What does “quantum-like” mean here? It means collective behavior with a quantum description — not tiny brains running Shor’s algorithm. The specific effect is superradiance, where many emitters act together and release energy faster than isolated emitters would. In Kurian’s framing, a single absorbed photon can create a shared excitation across many tryptophan sites in a filament. That shared state is the quantum-looking part. The paper then compares the speed limits of those excitations with the speed of conventional cellular signaling. (nature.com) ### Why are people talking about speed? Because the timescales are wildly different. Chemical signaling in cells often unfolds on microsecond to millisecond scales or slower. The superradiant dynamics invoked here happen on picosecond scales. That is why headlines started saying cells might “compute faster than quantum computers” — but that phrasing is doing a lot of work and can mislead. The paper is mostly about upper bounds and physical possibility, not a benchmark where a living cell beat an IBM chip on a task. (science.org) ### So did they prove cells are quantum computers? No. That is the catch. The Science Advances paper is theoretical and inferential. It assumes quantum mechanics, relativistic speed limits, and a recent experimental observation of superradiance in protein fibers, then derives a revised bound for life’s total possible information processing. That is very different from directly showing that intact human cells routinely use these states for decision-making, memory, or control. (thequantuminsider.com) ### Why are some scientists still interested? Because the idea is not obviously nonsense anymore. Quantum biology already has accepted footholds — photosynthesis, enzyme tunneling, bird magnetoreception are the usual examples. What makes this case provocative is the scale and the temperature: micron-scale protein structures in warm, wet biology. If that holds up, bioelectric signaling and intracellular coordination may need models that mix chemistry, electromagnetism, and collective quantum effects instead of treating them as separate layers. (science.org) ### What would real validation look like? Direct replication by independent labs. Then experiments showing that these superradiant states are not just physically present but biologically used — for example, that disrupting the relevant protein geometry changes signaling or behavior in a way classical models cannot explain. Until then, the safest read is that this is a serious but highly speculative framework sitting on top of one intriguing experimental foothold. (spj.science.org) ### Bottom line? The interesting part is not “cells are quantum computers.” They probably are not, at least not in the sci-fi sense. The interesting part is narrower and maybe more important — some of the cell’s internal scaffolding may double as a very fast signaling medium, and quantum optics might be part of the story. If that survives replication, cell biology gets a new layer. (science.org)