Quantum Secret of Photosynthesis Revealed
The magic of light capture by plants is so small and fast, its secrets are only now being understood.
Lightning is slow compared to photosynthesis. A press release from the Institute of Photonic Sciences (ICFO) explains how “antenna proteins” capture photons of sunlight and ferry the energy to reaction centers:
The efficient conversion of sunlight into useful energy is one of the challenges which stand in the way of meeting the world’s increasing energy demand in a clean, sustainable way without relying on fossil fuels. Photosynthetic organisms, such as plants and some bacteria, have mastered this process: In less than a couple of trillionths of a second, 95 percent of the sunlight they absorb is whisked away to drive the metabolic reactions that provide them with energy. The efficiency of photovoltaic cells currently on the market is around 20 percent. What hidden mechanism does nature use to transfer energy so efficiently? Various research groups around the world have shown that this highly efficient energy transport is connected to a quantum-mechanical phenomenon. However, until now, no one had directly observed the possible impacts of such a quantum transport mechanism at work at room temperature.
The quantum mechanical phenomenon is known as coherence. The way plants use it makes photosynthesis “more robust in the face of environmental influences,” the press release said.
Quantum coherence is manifested in so-called photosynthetic antenna proteins that are responsible for absorption of sunlight and energy transport towards the photochemical reaction centers where the energy is stored.
ICFO researchers used light flashes at femtosecond speeds (10-15 s, one quadrillionth of a second) to monitor the actions of these proteins in their work.
The most surprising discovery was that, while the transport paths within single proteins vary over time due to changes in the environmental conditions, the protein uses the quantum character to adapt for optimal efficiency. These results show that coherence, a genuine quantum effect of superposition of states, is responsible for maintaining high levels of transport efficiency in biological systems, even while they adapt their energy transport pathways due to environmental influences.
The press release includes a diagram of one of the antenna proteins, with the caption “natural quantum machines.” Photosynthesis operates not only in the leaves of plants, but also in algae and some bacteria.
How did “nature” master quantum coherence for optimal efficiency of light capture? How did plants develop “quantum machines” to achieve 475% better efficiency than man’s best intelligent design of photocells? When materialistic man cannot explain the exquisite design of natural processes by its blind, unguided processes, he worships “nature” as his substitute god.